Genetic and Evolutionary
Computation Conference 2015
Conference Program

Madrid, Spain
July 11-15, 2015

Welcome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Organizers and Track Chairs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Program Committee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Schedule and Floor Plans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Schedule at a Glance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Workshop and Tutorial Sessions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Paper Sessions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Floor Plans, Track List, and Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
nanoGECCO 2015 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tutorials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Workshops and Late Breaking Abstracts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Keynotes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Humies, Competitions, and Evolutionary Computation in Practice . . . . . . . . . . . . . . . . . . . . . .
Humies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Competitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Evolutionary Computation in Practice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Papers and Posters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Monday, July 13, 11:10-12:50 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Monday, July 13, 14:30-16:10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Monday, July 13, 16:40-18:45 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tuesday, July 14, 11:10-12:50 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tuesday, July 14, 14:30-16:10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tuesday, July 14, 16:40-18:20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wednesday, July 15, 12:25-14:05 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Poster Session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Abstracts by Track . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ant Colony Optimization and Swarm Intelligence . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Artificial Immune Systems and Artificial Chemistries . . . . . . . . . . . . . . . . . . . . . . . . . .
Artificial Life/Robotics/Evolvable Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Biological and Biomedical Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous Optimization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Digital Entertainment Technologies and Arts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Estimation of Distribution Algorithms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Evolutionary Combinatorial Optimization and Metaheuristics . . . . . . . . . . . . . . . . . . . . . .
Evolutionary Machine Learning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Evolutionary Multiobjective Optimization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Generative and Developmental Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Genetic Algorithms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Genetic Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hot Off the Press . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Integrative Genetic and Evolutionary Computation . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parallel Evolutionary Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Real World Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Search-Based Software Engineering and Self-* Search . . . . . . . . . . . . . . . . . . . . . . . . .
Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Instructions for Session Chairs and Presenters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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GECCO is sponsored by the Association for Computing Machinery Special Interest Group for Genetic and Evolutionary
Computation (SIGEVO). SIG Services: 2 Penn Plaza, Suite 701, New York, NY, 10121, USA, 1-800-342-6626 (USAand Canada) or +212-626-0500 (global).

1

Welcome3

It is my pleasure to welcome you to Madrid for the 2015 Genetic and Evolutionary Computation Conference – GECCO2015. This is a special year for several reasons. Firstly, sixteen years ago, in 1999, GECCO was born and held forthe first time in Orlando, Florida, USA. So happy birthday sweet sixteen, GECCO! We are now in our teenage
years, and still growing stronger. Second, thirty years ago the first ICGA, the International Conference on Genetic
Algorithms, was held in 1985. Several people who attended that event are still with us today to bear witness to thestrength of the (r)evolutionary ideas that were presented there. Thirdly, this year witnesses the highest ever proportionof women in the Organizing Committee, following the spirit of Women@GECCO. And last but not least, we haveaimed at introducing your kids to Genetic and Evolutionary Computation by means of the nanoGECCO event.
This year’s GECCO is comprised of 18 regular tracks, plus, for the second year, the Hot Off the Press (HOP) track,
which offers authors of outstanding research recently published in journals and other conferences the opportunity topresent their work to the GECCO community. Under the guidance of Editor-in-Chief Sara Silva, the Track Chairs
and Program Committee have selected 182 out of the 505 submissions received in all tracks (excluding HOP) for oralpresentation as full papers, resulting in an acceptance rate of 36%. Close to 100 short papers will be presented in theregular poster session. This year we also include an additional poster session, where late-breaking abstracts will bepresented together with student papers.
A highlight of the conference is the keynote talks given by salient figures in the GECCO fields of interest. This year
we wanted to enhance the experience by going back to our origins and have included a third talk from the Natural
Sciences field. Our speakers and their subjects are:
• Ricard Solé, “Re-designing nature with synthetic biology: from artificial ants and tissues to a new biosphere”,• Kate Smith-Miles, “Visualising the diversity of benchmark instances and generating new test instances to elicit
insights into algorithm performance”,• Manuel Martı́n-Loeches, “Origins and evolution of human language: saltation or gradualism?”.
Altogether 32 tutorials cover topics ranging from broad and introductory to specialized and at the frontier of current
research. GECCO also hosts fifteen workshops, including several new ones as well as at least one that predates
GECCO itself. Further high points include the 12th Annual“Humies” Awards for Human-Competitive Results, which
are again generously supported by John Koza, and a record number of nine competitions, ranging from Art to Industry.
Finally, Evolutionary Computation in Practice continues to be an important and integral part of GECCO, aiming at
getting us in touch with the “real world”.
All this would not have been possible without the hard work and dedication of the Organizing Committee over the
past year. First of all a special mention is due to Sara Silva, who did a superb job of maintaining the high qualityof the conference. Anabela Simões and Gisele Pappa ensured an interesting mixture of Tutorials and Workshops
respectively, while Mike Preuss was in charge of finding challenging Competitions. Katya Rodrı́guez-Vázquez’s
efforts were devoted to that key component which ensures the conference’s future development: the students. Şima
Etaner Uyar and Pablo Garcı́a-Sánchez made us reach the public via publicity and social media, and Juan Luis Jiménez
Laredo compiled all the useful information as Proceedings Chair. Thanks also go to the Track Chairs and the Program
Committee for their careful reviewing of the large number of submissions received, and to the workshop chairs andtutorial presenters.
Good advice is worth more than gold and here my sincerest acknowledgement goes to the SIGEVO Business Committee, Pier Luca Lanzi and Jürgen Branke, to SIGEVO Officers Wolfgang Banzhaf, Una-May O’Reilly, Marc Schoenauer
and Franz Rothlauf and to former GECCO chairs Dirk Arnold (2014) and Enrique Alba (2013). Finally, a big hand toIñaki Hidalgo and his team at the Universidad Complutense, as well as all the volunteers, who have ensured we all get
the fullest Madrid experience.
Of course, all this effort would not make any sense without you, who are reading this right now, and all GECCO’s
attendees. So thanks to you too and I wish you all a productive and enjoyable conference!

Anna I Esparcia Alcázar
General Chair

4

Organizers and Track Chairs

Organizers
General Chair:

Anna I. Esparcia-Alcázar, Universitat Politècnica de València, Spain

Editor-in-Chief:

Sara Silva, Universidade de Lisboa, Portugal

Proceedings Chair:
Local Chair:

Juan Luis Jiménez Laredo, Université du Havre, FranceJosé Ignacio (Iñaki) Hidalgo, Universidad Complutense de Madrid, Spain

Publicity Chair:Şima Etaner Uyar, İstanbul Teknik Üniversitesi, Turkey

Tutorials Chair:Anabela Simões, Instituto Politécnico de Coimbra, Portugal

Students Chair:

Katya Rodrı́guez-Vázquez , Universidad Nacional Autónoma de México

Workshops Chair:Gisele Pappa, Universidade Federal de Minas Gerais, Brazil

Competitions Chair:

Mike Preuss, Universität Münster, Germany

Social Media Chair:

Pablo Garcı́a-Sánchez, Universidad de Granada, Spain

Local Arrangements:
Late Breaking Abstracts Chair:
Evolutionary Computationin Practice:Business Committee:

SIGEVO Officers:

Luis Hernández-Yáñez, Universidad Complutense de Madrid, Spain
Dirk Sudholt, University of Sheffield, UK

Thomas Bartz-Beielstein, Fachhochschule Köln, GermanyJörn Mehnen, Cranfield University, UKJürgen Branke, University of Warwick, UK
Pier-Luca Lanzi, Politecnico di Milano, Italy
Wolfgang Banzhaf (Chair) Memorial University of Newfoundland,Canada
Una-May O’Reilly (Vice-chair) MIT, USA
Marc Schoenauer (Secretary) INRIA-Saclay, France
Franz Rothlauf (Treasurer) Universität Mainz, Germany

Organizers and Track Chairs

5

Track Chairs
Ant Colony Optimization and
Swarm Intelligence
Sanaz Mostaghim, OVG University Magdeburg
Manuel López-Ibáñez, Free University of Brussels
Artificial Immune Systems andArtificial Chemistries
Jon Timmis, University of York
Christine Zarges, University of Birmingham
Artificial Life/Robotics/Evolvable Hardware
Terry Soule, University of Idaho
Luı́s M. P. Correia, University of Lisbon
Biological and Biomedical Applications
Ryan Urbanowicz, Dartmouth College
Mario Giacobini, University of Torino
Continuous Optimization
Tobias Glasmachers, Ruhr-University Bochum
Youhei Akimoto, Shinshu University
Digital Entertainment Technologies and Arts
Amy K. Hoover, University of Malta
Francisco Fernández, University of Extremadura
Evolutionary Combinatorial Optimizationand Metaheuristics
Carlos Cotta, University of Málaga
Francisco B. Pereira, Polytechnic Institute of Coimbra
Estimation of Distribution Algorithms
Pedro Larrañaga, Technical University of Madrid
Marta Soto, ICIMAF
Evolutionary Machine Learning
Julia Handl, University of Manchester
Jan Koutnı́k, IDSIA

Evolutionary Multiobjective Optimization
Antonio Gaspar-Cunha, University of Minho
Heike Trautmann, University of Münster
Generative and Developmental Systems
JB Mouret, University Pierre and Marie Curie
Sebastian Risi, IT University of Copenhagen
Genetic Algorithms
Oliver Schuetze, Cinvestav-IPN
Ernesto Costa, University of Coimbra
Genetic Programming
Alberto Moraglio, University of Exeter
Krzysztof Krawiec, Poznan University of Technology
Integrative Genetic and Evolutionary Computation
Julian F. Miller, University of YorkPaweł Widera , Newcastle University
Parallel Evolutionary Systems
Stefano Cagnoni, Università degli Studi di ParmaJJ Merelo, University of Granada
Real World Applications
Emma Hart, Edinburgh Napier University
Leonardo Trujillo, Tijuana Institute of Technology
Search-Based Software Engineering and Self-*
SearchGabriela Ochoa, University of Stirling
Marouane Kessentini, University of Michigan
TheoryCarola Doerr, University Pierre and Marie Curie
Francisco Chicano, University of Málaga

6

Program Committee

Program Committee
Abbass, Hussein, University of New South Wales
Abdelbar, Ashraf, Brandon University
Abraham, Ajith, Machine Intelligence Research Labs
Acampora, Giovanni, Nottingham Trent University
Acan, Adnan, Eastern Mediterranean University
Adamatzky, Andrew, University of the West of England
Affenzeller, Michael, FH Hagenberg
Aguirre, Hernan, Shinshu University
Ahn, Chang Wook, Sungkyunkwan University
Ahrens, Barry, Nova Southeastern University
Alba, Enrique, University of Málaga
Alden, Kieran, University of YorkAler, Ricardo, Universidad Carlos III de Madrid
Alfaro-Cid, Eva, Instituto Tecnologico de Informatica
Ali, Shaukat, Simula Research Laboratory
Allmendinger, Richard, University College London
Alshahwan, Nadia, UCL
Alvarado Garcia, Sergio Jesus, CINVESTAV-IPN
Alves, Maria Joao, University of Coimbra
Amaya, Jhon Edgar, UNET
Amoretti, Michele, University of Parma
Amos, Ng, University of Skövde
Ankur, Sinha, Aalto University School of Economics
Antoniol, Giuliano, Ecole Polytechnique de Montreal
Antunes, Carlos, DEEC-UC
Arcuri, Andrea, Simula Research Laboratory
Arias Montaño, Alfredo, IPN-ESIME
Arita, Takaya, Nagoya University
Arnaldo, Ignacio, MIT
Arnold, Dirk V., Dalhousie University
Arvin, Farshad, University of Lincoln
Auerbach, Joshua E., École Polytechnique Fédérale deLausanne
Auger, Anne, INRIA
Aydin, Nizamettin, Yildiz Technical University
Aydin, Mehmet Emin, University of the West of England
Aydn, Dogan, Dumlupinar University
Azad, Raja Muhammad Atif, University of Limerick
Bacardit, Jaume, Newcastle University
Bader-El-Den, Mohamed, University of Essex
Badkobeh, Golnaz, University of Sheffield
Ballester, Pedro J., Cancer Research Centre of MarseilleBanzhaf, Wolfgang, Memorial University of Newfoundland
Baptista, Tiago, CISUC
Barbosa, Helio J.C., LNCC
Barros, Marcio, UNIRIO
Bartz-Beielstein, Thomas, Cologne University of Applied
Sciences
Bassett, Jeffrey K., Smithsonian Institute National Museum of
Natural History
Basseur, Matthieu, Université d’Angers
Beal, Jacob, BBN Technologies
Bechikh, Slim, University of Michigan-Dearborn
Belkhir, Nacim, Thales Research&Technology

Bentley, Peter J., University College London
Bergstra, James, University of Waterloo
Bernardino, Heder, DCC/UFJF
Bernt, Matthias, University Leipzig
Bersano, Tom, Google
Berthier, Vincent, Inria Tao
Besada-Portas, Eva, Universidad Compluntense de Madrid
Beyer, Hans-Georg, Vorarlberg University of Applied Sciences
Bezerra, Leonardo, IRIDIA
Bhanu, Bir, University of California at Riverside
Biazzini, Marco, INRIA - Bretagne Atlantique
Bielza, Concha, Technical University of Madrid
Biesinger, Benjamin, Vienna University of Technology
Birattari, Mauro, Université Libre de Bruxelles
Bischl, Bernd, TU Dortmund
Blackwell, Tim, Goldsmiths
Blekas, Konstantinos, University of Ioannina
Blesa, Maria J., Universitat Politècnica de Catalunya
Blum, Christian, University of the Basque Country
Bongard, Josh, University of Vermont
Bonyadi, Mohammadreza, The University of Adelaide
Booker, Lashon, The MITRE Corporation
Bosman, Peter A.N., Centre for Mathematics andComputer Science
Botazzo Delbem, Alexandre, University of So Paulo
Boudjeloud, Lydia, LITA
Boumaza, Amine, Université de Lorraine / LORIA
Bouvry, Pascal, University of Luxembourg
Bown, Ollie, University of Sydney
Brabazon, Anthony, University College Dublin
Branke, Juergen, University of Warwick
Bredeche, Nicolas, ISIR
Breen, David E., Drexel University
Bringmann, Karl, ETH Zurich
Brockhoff, Dimo, INRIA Lille - Nord Europe
Browne, Will Neil, Victoria University of Wellington
Brownlee, Alexander, University of Stirling
Bui, Thang, Penn State Harrisburg
Bui, Lam Thu, Le Quy Don Technical University
Buk, Zdenek, Czech Technical University in Prague
Bull, Larry, University of the West of England
Bullinaria, John A., University of Birmingham
Burelli, Paolo, Aalborg University Copenhagen
Burjorjee, Keki Mehernosh, Brandeis University
Butz, Martin V., University of Tübingen
Buzdalov, Maxim, ITMO University
Buzdalova, Arina, ITMO University
Byrski, Aleksander, AGH University of Science andTechnology
Cagnina, Leticia, Universidad Nacional de San Luis
Cai, Xinye, Nanjing University of Aeronautics andAstronautics
Cairns, David, University of Stirling
Campo, Alexandre, Université Libre de Bruxelles

Program Committee

Cangelosi, Angelo, University of Plymouth
Capodieci, Nicola, University of Modena and Reggio Emilia
Carmelo J A, Bastos Filho, University of Pernambuco
Carvalho, Andre, USP
Castelli, Mauro, NOVA IMSCastellini, Alberto, University of Verona
Castillo, Pedro, UGR
Cazarez-Castro, Nohe Ramon, Instituto Tecnologico de Tijuana
Ceschia, Sara, University of Udine
Chakraborty, Uday, University of Missouri
Chang, Pei-Chann, Yuan Ze University
Chelly, Zeineb, LARODEC
Chen, Yu-wang, Manchester Business School
Chen, Tianshi, ICT
Chen, Ying-ping, National Chiao Tung University
Cheney, Nick, Cornell University
Chiarandini, Marco, University of Southern Denmark
Chiong, Raymond, The University of Newcastle
Chong, Siang Yew, University of Nottingham
Chotard, Alexandre Adrien, INRIA
Christensen, Anders, Instituto de Telecomunicações /ISCTE-IUL
Chu, Dominique, University of Kent
Chuang, Chung-Yao, The Robotics InstituteClark, John, University of York
Clerc, Maurice, Independent Consultant
Clune, Jeff, University of Wyoming
Coelho, Leandro, Pontifical Catholic University of Parana
Coello Coello, Carlos A., CINVESTAV-IPN
Colby, Mitch K., Oregon State University
Colmenar, J. Manuel, Rey Juan Carlos University
Colton, Simon, Goldsmiths College
Connelly, Brian, University of Washington
Cook, Michael, Goldsmiths College
Cordon, Oscar, University of Granada
Costa, Ernesto, University of Coimbra
Costa, Lino António, University of Minho
Costa, M. Fernanda P., University of Minho
Craenen, Bart G.W., University of Edinburgh
Cully, Antoine, ISIR
Cummins, Ronan, University of Cambridge
Cussat-Blanc, Sylvain, University of Toulouse
D’Ambrosio, David B., University of Central Florida
Dahlskog, Steve, Malmö University
Dahlstedt, Palle, University of Gothenburg /Chalmers University of Technology
Dang, Duc-Cuong, University of Nottingham
Darabos, Christian, Dartmouth College
Das, Sanjoy, Kansas State University
Das, Angan, Intel
Datta, Rituparna, IIT Kanpur
Datta, Dilip, Tezpur University
David, Cornforth, University of New South Wales
De Causmaecker, Patrick, KU Leuven
De Jong, Kenneth, George Mason University
de la Fraga, Luis Gerardo, CINVESTAV

7

de la Ossa, Luis, Universidad de Castilla-La Mancha
Deakin, Anthony, University of Liverpool
Della Cioppa, Antonio, Natural Computation Lab - DIEM
Demircioglu, Aydin, Ruhr-Universität Bochum
Derbel, Bilel, INRIA USTL LIFL
Deutz, Andre, Leiden University
Dhaenens, Clarisse, LIFL / CNRS / INRIADi Caro, Gianni, IDSIADi Gaspero, Luca, University of Udine
Di Penta, Massimiliano, RCOST - University of Sannio
Diaz Ramirez, Victor, CITEDI-IPN
Ding, Yongsheng, Donghua University
Dinh, Huy, University of Tokyo
Dinneen, Michael J., University of Auckland
Divina, Federico, Pablo de Olavide University
Doerr, Benjamin, Ecole Polytechnique
Dominguez-Medina, Christian, CIC-IPN
Doncieux, Stéphane, ISIR/UPMC
Dorin, Alan, Monash University
Dorronsoro, Bernabe, University of Cadiz
Doursat, Rene, Institut des Systemes Complexes
Dozal, León, CICESE
Drchal, Jan, Department of Computer Science and Engineering
Drozdik, Martin, Shinshu University
Drugan, Madalina, AI-lab VUB
Dubois-Lacoste, Jérémie, IRIDIA
Dunn, Enrique, University of North Carolina
Ebner, Marc, Ernst-Moritz-Universität Greifswald
Ekart, Aniko, Aston University
El-Abd, Mohammed, American University of Kuwait
Emil-Savan, Emanuel, University of Manchester
Emmerich, Michael T. M., LIACSEngelbrecht, Andries P., University of Pretoria
Eremeev, Anton V., Omsk Branch of Sobolev
Institute of Mathematics
Espirito Santo, Isabel, University of Minho
Esponda, Fernando, ITAM
Everson, Richard, University of Exeter
Farooq, Muddassar, Institute of Space Technology
Feldt, Robert, Dept of Computer Science and Engineering
Fenet, Serge, Universite Lyon 1
Ferariu, Lavinia, Gheorghe Asachi Technical University of Iasi
Fernandez, Jose David, Université de Mons
Fernandez Martinez, Juan Luis, Universidad de Oviedo
Fernández Leiva, Antonio J., University of Málaga
Festa, Paola, Universitá degli Studi di Napoli
Fialho, Álvaro, GE Global Research
Fidanova, Stefka, Institute of Information andCommunication Technologies
Fieldsend, Jonathan Edward, University of Exeter
Figueredo, Grazziela, The University of Nottingham
Filipic, Bogdan, Jozef Stefan Institute
Finck, Steffen, Vorarlberg University of Applied Sciences
Fink, Andreas, Helmut-Schmidt-University
Fischer, Asja, Ruhr-University Bochum
Fleming, Peter, University of Sheffield

8

Folino, Gianluigi, ICAR-CNR
Fonseca, Carlos M., University of Coimbra
Foster, James A., University of Idaho
Franzin, Alberto, Université Libre de Bruxelles
Fraser, Gordon, University of Sheffield
Freisleben, Bernd, Universität Marburg
Freitas, Alex A., University of Kent
Friedrich, Tobias, University of Jena
Frowd, Charlie, University of Winchester
Gallagher, Marcus R., University of Queensland
Gallardo, Jose Enrique, Universidad de Málaga
Galvan, Edgar, Trinity College Dublin
Galway, Leo, University of Ulster
Gambardella, Luca Maria, IDSIA
Gamez, Jose A., Universidad de Castilla-La Mancha
Gandibleux, Xavier, Université de Nantes
Garcia-Nieto, Jose, University of Malaga
Garcia-Piquer, Alvaro, Institute of Space Sciences(IEEC-CSIC)
Garcia-Valdez, Mario, Instituto Tecnologico de Tijuana
Garcı́a Sánchez, Pablo, University of Granada
Garcı́a-Martı́nez, Carlos, Univ. of Córdoba
Garnier, Simon, New Jersey Institute of Technology
Garrett, Deon, Icelandic Institute for Intelligent Machines
Gauci, Jason, University of Central Florida
Gelareh, Shahin, University of Artois/ LGI2A
Ghosh, Arka, Indian Statistical Institute
Giagkiozis, Ioannis, The University of Sheffield
Giancarlo, Raffaele, University of Palermo
Giavitto, Jean-Louis, CNRS - IRCAM
Gieen, Christian, DTU Compute
Giugno, Rosalba, University of Catania
Giustolisi, Orazio, Technical University of Bari
Goeffon, Adrien, LERIA
Goh, Chi-Keong, Rolls-Royce Singapore
Goldbarg, Marco César, Universidade Federal do Rio Grande
do Norte
Goldman, Brian W., Michigan State University
Gomez-Pulido, Juan A., University of Extremadura
Gong, Wenyin, China University of Geosciences
Gonçalves, Ivo, University of Coimbra
Graff, Mario, Universidad Michoacanade San Nicolas de Hidalgo
Greenfield, Gary, University of RichmondGreensmith, Julie, University of Nottingham
Greiner, David, Universidad de Las Palmas de Gran Canaria
Grimme, Christian, Münster University
Gross, Roderich, The University of Sheffield
Grouchy, Paul, University of Toronto
Institute for Aerospace Studies
Gu, Feng, Kingston University
Guerreiro, Andreia P., University of Coimbra
Guinand, Frederic, Université Le Havre
Gutjahr, Walter J., University of Vienna
Haasdijk, Evert, VU University Amsterdam
Hamann, Heiko, University of Paderborn

Program Committee

Hamel, Lutz, University of Rhode Island
Hamzeh, Ali, Shiraz University
Hanafi, Said, university of Valenciennes
Handa, Hisashi, Kindai University
Hao, Jin-Kao, University of Angers - LERIAHarman, Mark, UCL
Harvey, Inman, University of Sussex
Hasle, Geir, SINTEF
Hastings, Erin, University of Central Florida
Hauert, Sabine, MIT
Hauschild, Mark W., University of Missouri-St. LouisHayashi, Shinpei, Tokyo Institute of Technology
He, Jun, University of Wales
Heidrich-Meisner, Verena, CAU Kiel
Hendtlass, Tim, Swinburne University of Technology
Hereford, James, Murray State University
Hernandez, Daniel Eduardo, CICESE
Hernández, Carlos, CINVESTAV-IPN
Hernández-Aguirre, Arturo, Centre for Researchin Mathematics
Hernández-Dı́az, Alfredo G., Pablo de Olavide University
Heywood, Malcolm, Dalhousie University
Hickinbotham, Simon John, University of York
Hingston, Philip, Edith Cowan University
Holena, Martin, Institute of Computer Science
Holmes, John H., University of Pennsylvania
Howard, Gerard, CSIRO
Hsiao, Michael, Virginia Tech
Hu, Bin, Technische Universität Wien
Hu, Jianjun, University of South Carolina
Hu, Ting, Memorial University
Huizinga, Joost, University of Wyoming
Husbands, Phil, Sussex University
Hutter, Frank, UBC
Iclănzan, David Andrei, Sapientia Hungaryan Universityof Transylvania
Igel, Christian, Department of Computer Science
Iida, Fumiya, ETH Zurich
Ikegami, Takashi, University of Tokyo
Iori, Manuel, University of Modena and Reggio Emilia
Ishibuchi, Hisao, Osaka Prefecture University
Istvan, Juhos, University of Szeged
Jackson, David, University of Liverpool
Janikow, Cezary Z., UMSL
Jansen, Thomas, Aberystwyth University
Jayadeva, Indian Institute of Technology
Jia, Yue, UCL
Jimenez Laredo, Juan Luis, University of Le Havre
Jin, Yaochu, University of Surrey
Johannsen, Daniel, SAP Innovation Center
Johansson, Ulf, University of Borås
Johnson, Colin Graeme, University of Kent
Johnston, Mark, Victoria University of Wellington
Joshi, Ayush, University of Birmingham
Jourdan, Laetitia, INRIA Lille Nord Europe
Julstrom, Bryant Arthur, St. Cloud State University

Program Committee

Kaban, Ata, University of Birmingham
Kampouridis, Michael, University of Kent
Karthik, Sindhya, University of Jyväskylä
Kattan, Ahmed, UQU
Kerschke, Pascal, University of Münster
Khan, Gul Muhammad, NWFP University of Engineeringand Technology
Khare, Vineet, Amazon Development Centre (India) Pvt ltd
Kimura, Shuhei, Tottori Universit
Kipouros, Timoleon, University of Cambridge
Kirley, Michael, University of Melbourne
Kirshenbaum, Evan, HP Labs
Knowles, Joshua D., University of Manchester
Koch, Patrick, Cologne University of Applied Sciences
Koeppen, Mario, Kyushu Institute of Technology
Kolodziej, Joanna, Cracow University of Technology
Komosinski, Maciej, Poznan University of Technology
Konen, Wolfgang, Cologne University of Applied Sciences
Kontis, Lysimachos, University of Ioannina
Korb, Oliver, Cambridge Crystallographic Data Centre
Kotsireas, Ilias, WLU
Kovacic, Miha, University Of Nova Gorica
Kramer, Oliver, University of Oldenburg
Kratica, Jozef, Mathematical InstituteKrause, Oswin, University of Copenhagen
Kronberger, Gabriel, Unversity of Applied Sciences
Upper Austria
Kubalik, Jiri, CTU PragueKötzing, Timo, MPI-INF
Künnemann, Marvin, Max-Planck-Institut für Informatik
Lamont, Gary Byron, AF Institute of Technology
Lampinen, Jouni, University of Vaasa
Landa, Ricardo, Cinvestav Tamaulipas
Landa-Silva, Dario, University of Nottingham
Langdon, William B., University College London
Lanzi, Pier Luca, Politecnico di Milano
Lara, Adriana, CINVESTAV-IPN
Lara-Cabrera, Raul, University of Malaga
LaTorre, Antonio, Universidad Politécnica de MadridLau, Henry, The University of Hong Kong
Lau, Hoong-Chuin, Singapore Management University
Le Goues, Claire, Carnegie Mellon University
Legrand, Pierrick, Université de BordeauxLeguizamon, Guillermo, Universidad Nacional de San Luis
Lehman, Joel, The University of Texas at Austin
Lehre, Per Kristian, University of Nottingham
Leibnitz, Kenji, National Institute of Information
and Communications Technology
Lengler, Johannes, ETH Zurich
Leo, Cazenille, Université Paris 7 Diderot - LIED Team
Leon, Coromoto, Universidad de La Laguna
Lessin, Dan, The University of Texas at Austin
Leung, Kwong Sak, The Chinese University of Hong Kong
Lewis, Matthew, The Ohio State University
Lewis, Peter R., Aston University
Leyva López, Juan Carlos, Universidad de Occidente

9Li, Ke, Department of Electrical and Computer Engineering
Li, Xiaoou, CINVESTAV-IPN
Li, Xianneng, Graduate School of Information
Liang, Feng, Nanyang Technological University
Liang, Yiwen, Wuhan University
Liao, Tianjun, IRIDIA
Liapis, Antonios, Center for Computer Games Research
Lichodzijewski, Peter, Dalhousie University
Liefooghe, Arnaud, Université Lille 1
Limmer, Steffen, University Erlangen
Ling, Ping, Jiangsu Normal University
Lipinski, Piotr, Computational Intelligence Research Group
Lissovoi, Andrei, Technical University of Denmark
Liu, Jialin, TAO
Liu, Bo, Academy of Mathematics and Systems Science
Lobo, Daniel, Tufts University
Lobo, Fernando G., University of Algarve
Loiacono, Daniele, Politecnico di Milano
Lones, Michael, Heriot-Watt University
Lopes, Rui, University of CoimbraLópez-Jaimes, Antonio, CINVESTAV
Loshchilov, Ilya, INRIALouis, Sushil, UNR
Lourenço, Nuno, Universidade de Coimbra
Lozano, Manuel, University of Granada
Lozano, Jose A., University of the Basque Country
Lu, Emiao, Manchester Business School
Lucas, Simon, University of Essex
Ludwig, Simone A., North Dakota State University
Luna, J. M., University of Cordoba
Luna, Francisco, University of Extremadura
Luo, Wenjian, University of Science and Technology of China
Lust, Thibaut, UPMC
Lygoe, Robert J., Ford Motor Co Ltd
Lyon, Robert, University of Manchester
Mabu, Shingo, Yamaguchi University
Machado, Penousal, University of Coimbra
Madureira, Ana Maria, Polytechnic Institute of Porto
Maisto, Domenico, Institute for High Performance Computing
and Networking
Majercik, Stephen, Bowdoin College
Malago, Luigi, Shinshu University
Maldonado, Yazmin, Instituto Tecnologico de TijuanaMalo, Pekka, Aalto University School of Business
Mambrini, Andrea, University of Birmingham
Manderick, Bernard, VUB
Mandziuk, Jacek, Faculty of Mathematics and Information
Science
Mansor, Maszatul M., University of Sheffield
Manzoni, Luca, Università degli Studi di Milano-Bicocca
Marchiori, Elena, Radboud University
Maria, Ana, University of Minho
Marinakis, Yannis, Technical University of Crete
Maringer, Dietmar, University of BaselMartin, Simon, University of Stirling
Martin, Andrew, Dept Biochem & Mol Biol

10

Martinez, Hector P., IT-Universitetet i Kbenhavn
Martinez, Ivette C., Universidad Simon Bolivar
Martı́, Luis, Pontifı́cia Universidade Católica do Rio de Janeiro
Mascia, Franco, Université Libre de Bruxelles
Masegosa, Antonio D., University of Deusto
Maslov, Igor V., EvoCo Inc
Matsui, Shouichi, SERL
Mauri, Giancarlo, University Milano-Bicocca
Mavrovouniotis, Michalis, De Montfort University
Mayer, Helmut A., University of Salzburg
McDermott, James, University College Dublin
McMinn, Phil, University of Sheffield
McPhee, Nicholas Freitag, University of Minnesota
Mehnen, Jorn, Cranfield University
Meignan, David, University of Osnabrück
Meisel, Stephan, Münster University
Melab, Nouredine, Université Lille 1
Melkozerov, Alexander, Tomsk State University ofControl Systems and Radioelectronics
Mendes, Rui, CCTC/UM
Mendiburu, Alexander, University of the Basque Country
Menzel, Stefan, Honda Research Institute Europe
Menzies, Tim, ComSci / NcState University
Merigo Lindahl, Jose M., University of Barcelona
Mersmann, Olaf, TU Dortmund
Mesejo Santiago, Pablo, INRIA
Meyer-Nieberg, Silja, Universitaet der Bundeswehr Muenchen
Meyer, Bernd, Monash University
Mezura-Montes, Efren, University of Veracruz
Miconi, Thomas, The Neurosciences Institute
Middendorf, Martin, University of Leipzig
Miikkulainen, Risto, The University of Texas at Austin
Miklic, Damjan, University of Zagreb
Mills, Rob, University of Lisbon
Minku, Leandro, The Centre of Excellence for Researchin Computational Intelligence and Applications
Miramontes Hercog, Luis, Self-Organizing Solutions
Miranda, Eduardo Reck, University of Plymouth
Misir, Mustafa, University of Freiburg
Mitchell, George, CCKF Ltd
Moen, Hans Jonas Fossum, Norwegian Defence Research
Estblishment
Mohan, Chilukuri K., Syracuse University
Molina, Julian, University of Malaga
Montanier, Jean-Marc, BSC
Montemanni, Roberto, Dalle Molle Institute for Artificial
Intelligence
Montes de Oca, Marco A., University of Delaware
Mora, Antonio, University of Granada
Moses, Melanie, University of New Mexico
Motsinger, Alison, North Carolina State University
Muelas, Santiago, Universidad Politécnica de Madrid
Musliu, Nysret, Vienna University of Technology
Nakib, Amir, Laboratoire LISSI
Narukawa, Kaname, Honda Research Institute Europe GmbH
Naujoks, Boris, Cologne University of Applied Sciences

Program Committee

Nebro, Antonio, University of Málaga
Neruda, Roman, Institute of Computer Science of ASCR
Neumann, Frank, The University of Adelaide
Nguyen Xuan, Hoai, Hanoi University
Nicolau, Miguel, University College Dublin
Nievola, Julio Cesar, PUCPR
Nitschke, Geoff, University of Cape Town
Nobile, Marco, Università degli Studi di Milano-Bicocca
Nojima, Yusuke, Osaka Prefecture University
Noman, Nasimul, University of Newcastle
Ó Cinnéide, Mel, National University of Ireland
O’Neill, Michael, University College Dublin
O’Riordan, Colm, NUI
Ofria, Charles, Michigan State University
Oh, Choong Kun, U.S. Naval Research Laboratory
Okabe, Tatsuya, Honda Research Institute Japan
Olhofer, Markus, Honda Research Institute Europe GmbH
Oliveira, Pedro, University of Porto
Oliveto, Pietro S., The University of SheffieldOliwa, Tomasz, The University of Georgia
Olmo, Juan Luis, University of Cordoba
Omran, Mohammed, Gulf University for Science& Technology
Ono, Isao, Tokyo Institute of Technology
Orsenigo, Carlotta, Politecnico di Milano
Ortega, Julio, Universidad de Granada
Osaba, Eneko, Deusto University
Otero, Fernando, University of Kent
Ouni, Ali, University of Montreal
Paechter, Ben, Edinburgh Napier University
Pagnozzi, Federico, Université Libre de Bruxelles
Palafox, Leon, The University of Arizona
Palmer, Michael E., Stanford University
Pang, Wei, University of Aberdeen
Paquete, Luis, University of Coimbra
Parque, Victor, Toyota Technological InstituteParsopoulos, Konstantinos, University of Ioannina
Pasquier, Philippe, SIAT - Simon Fraser University
Pedro, Castillo, UGR
Pellegrini, Paola, IRIDIA-CoDE ULBPenev, Kalin, Southampton Solent University
Perez Caceres, Leslie, Iridia - ULB
Peña, Jose-Maria, Universidad Politécnica de Madrid
Phelps, Steve, University of Essex
Philippides, Andrew, University of Sussex
Pillay, Nelishia, University of KwaZulu-Natal
Pilát, Martin, Faculty of Mathematics And Physics
Pizzuti, Clara, Institute for High Performance Computing
and Networking
Polani, Daniel, University of Hertfordshire
Poles, Silvia, EnginSoft
Pop, Petrica, North University of Baia Mare
Popovici, Elena, Icosystem Corp
Porumbel, Daniel, CEDRIC
Potter, Walter, University of Georgia
Poulding, Simon, Blekinge Institute of Technology

Program CommitteePošı́k, Petr, Czech Technical University in Prague
Prandtstetter, Matthias, AIT Austrian Institute of Technology
Prestwich, Steve, University College Cork
Puchinger, Jakob, AIT - Austrian Institute of Technology
Puente, Cesar, Universidad Autónoma de San Luis Potosi
Puerta, Jose Miguel, UCLM
Punch, William F., Michigan State University
Purshouse, Robin, University of Sheffield
Qi, Jianlong, Ancestry.com
Qin, A. K., RMIT University
Raidl, Günther R., Vienna University of Technology
Randall, Marcus Christian, School of Information Technology
Ranjithan, Ranji S., North Carolina State Univ
Rasheed, Khaled, University of Georgia
Ray, Tom, University of Oklahoma
Ray, Tapabrata, School of Aerospace
Raymer, Michael, Wright State University
Read, Mark, University of Sydney
Reed, Patrick M., Cornell University
Rhyd, Lewis, Cardiff University
Richter, Hendrik, HTWK Leipzig Universityof Applied Sciences
Rieffel, John, Union College
Riff, Maria Cristina, UTFSM
Robert, Wille, University of Bremen
Robilliard, Denis, LISIC
Rockett, Peter, Dept of Electronic & Electrical Engineering
Rodriguez-Tello, Eduardo, CINVESTAV
Rohlfshagen, Philipp, Schneider-ElectricRoli, Andrea, Alma Mater Studiorum Università di Bologna
Rombo, Simona E., Dep. of Mathematics and Computer
Science
Romero, Carlos, Technical University of Madrid
Roper, Marc, University of Strathclyde
Ross, Peter, Napier University
Ross, Brian J., Brock University
Rothlauf, Franz, University of Mainz
Rowe, Jonathan, University of Birmingham
Rudolph, Guenter, TU Dortmund University
Ruhe, Guenther, University of Calgary
Ruiz, Ruben, Polytechnic University of Valencia
Runkler, Thomas, Siemens AG
Ryan, Conor, University of Limerick
Sagarna, Ramon, University of the Basque Country
Sahin, Erol, Middle East Technical University
Sahraoui, Houari, DIRO
Sakuma, Jun, University of Tsukuba
Salem, Ziad, Graz University
Sanchez, Luciano, Universidad de Oviedo
Santana, Roberto, University of the Basque Country(UPV/EHU)
Santibáñez Koref, Iván, Technical Univ. Berlin
Sarro, Federica, University College London
Sato, Hiroyuki, The University of Electro-Communications
Sato, Yuji, Hosei University
Saubion, Fredéric, University of Angers

11

Sawada, Hideyuki, Kagawa University
Schaefer, Robert, AGH University of Science and Technology
Schillaci, Massimiliano, STMicroelectronics
Schmitt, Manuel, University of Erlangen-Nuremberg
Schoenauer, Marc, INRIA
Scully, Peter, Aberystwyth University
Sebag, Michele, Université Paris-Sud
Segura, Carlos, Universidad de La Laguna
Sekanina, Lukas, Brno University of Technology
Semet, Yann, Thales
Sen, Sandip, University of Tulsa
Seppi, Kevin, Brigham Young University
Serpell, Martin, University of the West of England
Sevaux, Marc, Université de Bretagne-Sud - Lab-STICC
Sezerman, Ugur, Sabanc University
Shaheen, Fatima, Loughborough University
Shaker, Noor, IT University of Copenhagen
Shakya, Siddhartha, Business Modelling &Operational Transformation Practice
Shapiro, Jonathan Lee, University of Manchester
Shengxiang, Yang, De Montfort Unviersity
Shukla, Pradyumn Kumar, KIT
Siarry, Patrick, University of Paris-Est Créteil
Silva, Arlindo, Polytechnic Institute of Castelo Branco
Silva, Fernando, Instituto de Telecomunicações; BioISI
Sim, Kevin, Edinburgh Napier University
Sipper, Moshe, Ben-Gurion University
Skurikhin, Alexei N., Los Alamos National Laboratory
Smith, Jim, University of the West of England
Smith, Alice, Auburn University
Smyth, Tamara, University of Califronia San Diego
Solnon, Christine, LIRIS
Solteiro Pires, Eduardo J., UTAD University
Soltoggio, Andrea, Loughborough University
Song, Andy, RMIT University
Sosa Hernandez, Victor Adrian, CINVESTAV-IPN
Sossa, Humberto, Instituto Politécnico Nacional
Souza, Jerffeson, State University of Ceara
Spector, Lee, Hampshire College
Squillero, Giovanni, Politecnico di Torino
Standish, Russell, High Performance Coders
Stepney, Susan, University of York
Stich, Sebastian, Université Catholique de Louvain
Stonedahl, Forrest, Northwestern University
Straccia, Umberto, ISTI-CNR
Stracquadanio, Giovanni, University of Oxford
Stützle, Thomas, Université Libre de Bruxelles
Sudholt, Dirk, University of Sheffield
Suganthan, Ponnuthurai, NTU
Sun, Yi, Google Inc
Sun, Chaoli, Taiyuan University of Science and Technology
Sutton, Andrew Michael, Friedrich-Schiller-Universität Jena
Suzuki, Reiji, Nagoya University
Takadama, Keiki, UEC
Takahashi, Ricardo, Universidade Federal de Minas Gerais
Talbi, El-Ghazali, INRIA

12

Tan, Ying, Peking University
Tanaka, Kiyoshi, Shinshu University
Tanev, Ivan, Faculty of Engineering
Tarantino, Ernesto, ICAR - CNR
Tauritz, Daniel R., Missouri University of Scienceand Technology
Tavares, Jorge, Microsoft
Tavares, Roberto, UFSCAR
Taylor, Tim, University of London International Academy
Teich, Jürgen, University of Erlangen-Nuremberg
Terashima Marı́n, Hugo, ITESM - CSI
Tettamanzi, Andrea G. B., Université de Nice Sophia Antipolis
Teuscher, Christof, Portland State University
Textor, Johannes, University of Utrecht
Teytaud, Fabien, University of Lille Nord de France
Thawonmas, Ruck, Ritsumeikan University
Thiele, Lothar, ETH ZurichThierens, Dirk, Utrecht University
Thompson, Tommy, University of Derby
Ting, Chuan-Kang, Department of Computer Scienceand Information Engineering
Tino, Peter, University of Birmingham
Tinos, Renato, University of So Paulo
Tiwari, Ashutosh, Cranfield University
Tiwari, Santosh, General Motors Company
Togelius, Julian, IT University of Copenhagen
Tomassini, Marco, University of Lausanne
Tonda, Alberto Paolo, INRA
Trefzer, Martin, University of York
Trianni, Vito, ISTC-CNR
Trojanowski, Krzysztof, Institute of Computer Science
Trunfio, Giuseppe A., University of Sassari
Tsoukias, Alexis, Université Paris Dauphine
Tuci, Elio, Aberystwyth University
Tuma, Matthias, Ruhr-Universität Bochum
Tusar, Tea, Jozef Stefan Institute
Tutum, Cem Celal, Michigan State University
Twycross, Jamie, University of Nottingham
U, Man Chon, Las Vegas Sands Corporate
Ugolotti, Roberto, University of Parma
Urbano, Paulo, University of Lisbon
Urquhart, Neil, Edinburgh Napier University
Vašı́ček, Zdeněk, Brno University Of Technology
Valencia-Palomo, Guillermo, Instituto Tecnologico
de Hermosillo
Van den Herik, H. Jaap, Tilburg University
Vanneschi, Leonardo, NOVA IMS
Vatolkin, Igor, TU Dortmund
Veerapen, Nadarajen, University of Stirling
Velasco, Nubia, Universidad de los Andes
Ventura, Sebastian, Universidad de Cordoba
Verbancsics, Phillip, Space and Naval Warfare Systems

Program Committee

Center - PacificVerel, Sebastien, Université du Littoral Côte d’Opale
Vergilio, Silvia, Federal University of Paraná
Viana, Ana, INESC TEC
Vidnerova, Petra, Institute of Computer Science of ASCR
Von Zuben, Fernando J., Unicamp
Vrahatis, Michael N., University of Patras
Wagner, Tobias, Institute of Machining Technology
Wanka, Rolf, University of Erlangen-Nuremberg
Weimer, Westley, University of Virginia
Wessing, Simon, Technische Universität Dortmund
Whigham, Peter Alexander, University of Otago
White, David, University of Glasgow
Wieloch, Bartosz, Poznan University of Technology
Wilkerson, Josh, NAVAIR
Wilson, Garnett, Afinin Labs Inc
Wilson, Stewart W., Prediction Dynamics
Wimmer, Manuel, Vienna University of Technology
Wineberg, Mark, University of Guelph
Winkler, Stephan, University Of Applied Sciences
Upper Austria
Witt, Carsten, Technical University Of Denmark
Wong, M. L. Dennis, Swinburne University of Technology
Woodward, John R., STIRLINGUNI
Wright, Alden H., University of Montana
Wrobel, Borys, Adam Mickiewicz University
Wu, Annie S., University of Central Florida
Xie, Huayang, Oracle New Zealand
Yamada, Takeshi, NTT Communication Science Labs
Yamamoto, Lidia, University of Strasbourg
Yannakakis, Georgios, IT University of Copenhagen
Yeh, Wei-Chang, National Tsing Hua University
Yen, Gary G., Oklahoma State University
Yoo, Shin, University College London
Yosinski, Jason, Cornell University
Yu, Tian-Li, Taiwan Evolutionary Intelligence Lab
Yu, Tina, Memorial University
Yu, Yang, Nanjing University
Zaefferer, Martin, Cologne University of Applied Sciences
Zafra, Amelia, University of Cordoba
Zahadat, Payam, Artificial Life Lab
Zaharie, Daniela, West University of Timisoara
Zambetta, Fabio, RMIT University
Zapotecas Martı́nez, Saúl, CINVESTAV-IPN
Zell, Andreas, University of Tübingen
Zexuan, Zhu, Shenzhen University
Zhang, Fu, Mathworks
Zhang, Yuanyuan, University College London
Zhang, Mengjie, Victoria University of Wellington
Zhong, Yanfei, Wuhan University
Zhou, Aimin, Department of Computer ScienceSchedule and Floor Plans

Schedule and Floor Plans

15

Schedule at a Glance
Saturday, July 11

Sunday, July 12

Monday, July 13

Tuesday, July 14

Wednesday, July 15

SIGEVO meeting

Opening 9:00-9:30
Tutorials and Workshops Tutorials and Workshops

9:00-10:50

KeynoteKeynoteRicard Solé

Kate Smith-Miles

9:30-10:40

9:30-10:40

9:00-10:40

Paper sessions,

Paper sessions,M. Martín-Loeches

nanoGECCO, EC inpractice

Hot Off the Press andnanoGECCO

11:10-12:10

9:00-10:50

Coffee break
KeynoteTutorials and Workshops Tutorials and Workshops

and Competitions
11:10-13:00

11:10-13:00

11:10-12:50

11:10-12:50
Paper Sessions
12:25-14:05

Lunch on your own

Paper sessions,
EC in practice andTutorials and Workshops Tutorials and Workshops Humies,
Competitions
14:30-16:20

14:30-16:20

Paper sessions,
Hot Off the Press

14:30-16:10

14:30-16:10

Paper sessions,

Paper sessions,

EC in practice, Hot Off
the Press

Hot Off the Press

16:40-18:30

16:40-18:45

16:40-18:20

Work/life balance panel

Posters

Coffee break

Tutorials and Workshops Tutorials and Workshops
16:40-18:30

18:30-20:00
18:45-20:45
Welcome reception

Spanish Tapas reception

20:00-22:00

20:00-23:00

Registration desk hours: Saturday and Sunday, 8:30-17:00 (closed during lunch)Monday, 8:30-17:00 (closed during lunch)
Tuesday, 9:00-18:00 (closed during lunch)
Wednesday, 8:30-11:00
Keynotes and SIGEVO meeting: Auditorium
Welcome reception, posters and competitions: Tapices room
Spanish Tapas reception venue: Teatro RealOur volunteers can take you there in a guided tour; please let us know if you are interested (sign on at theregistration desk). Tours will leave the hotel lobby at 18:30.

Schedule and Floor Plans

17

Workshop and Tutorial Sessions, Saturday, July 11

9:00-10:50
DoblónEscudo11:10−13:00

14:30−16:20

16:40−18:30

Runtime Analysis ofParameterized
Particle Swarm
Computation
Evolutionary Algorithms: Complexity Analysis of Evolutionary
Optimization
for Dynamic Optimization
Basic
introduction(Lehre,Evolutionary
Algorithms(Engelbrecht)
Problems (Yang)
Oliveto)(Neumann, Sutton)
Blind No More:
Synergies between
Constant Time NonMedical
ApplicationsofRepresentations
for
Evolutionary Algorithms Evolutionary Computation Evolutionary Algorithms
Random Improving
and Reinforcement
Moves and Exponentially(Smith)(Rothlauf)
Learning (Drugan)Powerful Recombination(Whitley)

Comendador

Student Workshop

HidalgoGenerative and
SecDef – Genetic and evolutionary computation in Developmental Systems
defense, security and risk management(Stanley)

Alcalá

Algorithms
VizGEC - Visualisation Evolutionary
for Protein Structure
Methods in Genetic andEvolutionary Computation Modeling (Shehu, De
Jong)Patio 1

Patio 2

Patio 3Hyper-heuristics(Woodward, Tauritz)

Automatic (Offline)
Optimization Evolutionary Robotics
Configuration ofGene Regulatory Networks Continuous
and
CMA-ES(Hansen, (Bredeche, Doncieux,
Algorithms (López(Cussat-Blanc, Banzhaf)
Akimoto)Mouret)Ibáñez, Stützle)
Solving complex
problems with
Theory of Evolution
Genetic Programming
Cartesian Genetic
coevolutionary
Strategies and Related(O'Reilly)
Programming(Miller)algorithms (Heywood,
Algorithms (Akimoto)Krawiec)
Constraint-Handlingor no cost distributed
Techniques used with Low
EvoSoft - Evolutionary Computation Software
evolutionary computation
Evolutionary Algorithms
Systems(Merelo)(Coello)Workshops
Introductory tutorials
Advanced tutorials
Specialized tutorials

Schedule and Floor Plans

19

Workshop and Tutorial Sessions, Sunday, July 12

11:10−13:00

DoblónIntelligent Systems for
Smart Cities (Alba)

Complex Networks(Tomassini)

Multimodal
Theory of Swarm
Optimization (Preuss) Intelligence (Sudholt)

EscudoEvolving Neural
Networks(Miikkulainen)

Evolutionary Image
Analysis and Signal
Processing (Zhang,Cagnoni)

Evolutionary
Computation: A
Work-Life
Unified Approach (De Women@GECCO balance panel
Jong)
Evolutionary
Expressive Genetic
Multiobjective
Programming
Optimization(Spector)(Brockhoff, Wagner)

Comendador

ECADA - Evolutionary Computation for theAutomated Design of Algorithms

HidalgoModel-Based
Evolutionary
Algorithms (Thierens,
Bosman)Semantic Genetic
Programming(Krawiec, Moraglio)

14:30−16:20

16:40−18:30

18:30-20:00

9:00-10:50

Semantic Methods in Genetic Programming

Alcalá

GI - Genetic Improvement

MedGEC - Medical Applications of Genetic
and Evolutionary Computation

Patio 1

Evolutionary Computation in Computational
Structural Biology

Evolving Collective Behaviors in Robotics

Patio 2Introducing
Evolutionary Rulebased Machine
Learning : A Practical
Guide (Urbanowicz,
Browne)Patio 3BBOB - Blackbox Optimization Benchmarking MetaDeeP - Metaheuristic Design Patterns

Tapices

Poster setup

Evolutionary Rule-based Machine Learning (former IWLCS)

Late-breaking
abstracts (LBA) andstudent posters

Workshops
Introductory tutorials
Advanced tutorials
Specialized tutorials

Women@GECCO
posters

Schedule and Floor Plans

21

Parallel Sessions, Monday, July 13 through Wednesday, July 15

MondayMondayMondayTuesday

Tuesday

Tuesday

Wednesday

July 13

July 13

July 13

July 14

July 14

July 14

July 15

11:10-12:50

14:30-16:10

16:40-18:45

11:10-12:50

14:30-16:10

16:40-18:20

12:25-14:05

Doblon

RWA1

RWA2 (BPA)

RWA3

ECOM2

ECOM3 (BPA)ECOM4IGEC +ECOM5

Escudo

ECiP1

ECiP2

ECiP3

HOP2

HOP3

HOP4

THEORY4

Comendador

AIS-ACHEM

GDS1 + PES1

HOP1

ACO-SI3

CO2

EML1 (BPA)

EML2

HidalgoEMO1

EMO2 (BPA)

ALIFE1

EMO3

EMO4

EMO5

EMO6

Alcalá

GA1 (BPA)

GA2

GA3

nanoGECCO

THEORY2 +EDA2GA4 + THEORY3

CO3

Patio 1nanoGECCOHUMIES

BIO1+DETA1+
PES2 (BPA)

CO1 (BPA)

SBSE-SS 2

ALIFE2+GDS2
(BPA)

EDA3

Patio 2

GP1

GP2

ECOM1

GP3

GP4 (BPA)GP5

ALIFE3

Patio 3

ACO-SI1 (BPA)

ACO-SI2

SBSE-SS1 +EDA1 +
THEORY1 (BPA)

DETA2

RWA4

BIO2+RWA5

SBSE-SS3

Tapices

COMPETITIONS COMPETITIONS(BPA): The session includes best paper award nominees.

Schedule and Floor Plans

Floor Plans

23

Schedule and Floor Plans

Track List and Abbreviations

ACO-SI: Ant Colony Optimization and Swarm Intelligence
AIS-ACHEM: Artificial Immune Systems and Artificial Chemistries
ALIFE: Artificial Life/Robotics/Evolvable Hardware
BIO: Biological and Biomedical Applications
CO: Continuous Optimization
DETA: Digital Entertainment Technologies and Arts
ECiP: Evolutionary Computation in Practice
ECOM: Evolutionary Combinatorial Optimization and Metaheuristics
EDA: Estimation of Distribution Algorithms
EML: Evolutionary Machine Learning
EMO: Evolutionary Multiobjective Optimization
GDS: Generative and Developmental Systems
GA: Genetic Algorithms
GP: Genetic Programming
HOP: Hot Off the Press
IGEC: Integrative Genetic and Evolutionary Computation
PES: Parallel Evolutionary Systems
RWA: Real World Applications
SBSE-SS: Search-Based Software Engineering and Self-* Search
THEORY: Theory25

nanoGECCO 2015

29

nanoGECCO 2015

The nanoGECCO (GECCO*10−9 ) event is aimed at the kids aged 12-16 that come with theirparents to GECCO and want to find out what this is all about. Here they can give their firststeps in Genetic and Evolutionary Computation and learn by playing games!

Kids can sign up for one or two sessions:
Session 1: Monday 11:10–12:50 Room: Patio 1
Session 2: Tuesday 11:10–12:50 Room: Alcalá

Activities led by:
Una-May O’Reilly (MIT),Terence Soule (University of Idaho),
JJ Merelo (Universidad de Granada)

Find out more at the registration desk.

Tutorials

32

Tutorials

Intoductory Tutorials
Particle Swarm Optimization
Andries Engelbrecht, Michigan State University, USA

Saturday, July 11, 9:00-10:50
Doblón

Runtime Analysis of Evolutionary Algorithms: Basic Introduction
Per Kristian Lehre, University of Nottingham, UK
Pietro S. Oliveto, University of Sheffield, UK

Saturday, July 11, 11:10-13:00
Doblón

Genetic Programming
Una-May O’Reilly, Massachusetts Institute of Technology, USA

Saturday, July 11, 11:10-13:00
Patio 2

Representations for Evolutionary Algorithms
Franz Rothlauf, University of Mainz, Germany

Saturday, July 11, 14:30-16:20
EscudoContinuous Optimization and CMA-ES
Nikolaus Hansen, INRIA, France
Youhei Akimoto, Shinshu University, Japan

Saturday, July 11, 14:30-16:20
Patio 1

Cartesian Genetic Programming
Julian Miller, University of York, UK
Andrew Turner, University of York, UK

Saturday, July 11, 14:30-16:20
Patio 2Hyper-heuristics
John R. Woodward, University of Stirling, UK
Daniel Tauritz, Missouri University of Science and Technology, USA

Saturday, July 11, 16:40-18:30
AlcaláEvolutionary Robotics
Nicolas Bredeche, Université Pierre et Marie Curie, FranceStéphane Doncieux, Université Pierre et Marie Curie, France
Jean-Baptiste Mouret, Institute for Intelligent Systems and Robotics -UPMC,FranceSaturday, July 11, 16:40-18:30
Patio 1

Evolving Neural Networks
Risto Miikkulainen, University of Texas at Austin, USA

Sunday, July 12, 9:00-10:50
EscudoModel-Based Evolutionary Algorithms
Dirk Thierens, Utrecht University, The Netherlands
Peter Bosman, Centre for Mathematics and Computer Science, The Netherlands

Sunday, July 12, 9:00-10:50
HidalgoIntroducing Rule-based machine learning - A Practical Guide
Ryan Urbanowicz, University of Pennsylvania, USA
Will Browne, Victoria University of Wellington, New ZealandSunday, July 12, 9:00-10:50
Patio 2Complex Networks
Marco Tomassini, University of Lausanne, Switzerland

Sunday, July 12, 11:10-13:00
DoblónMultimodal Optimization
Mike Preuss, University of Münster, Germany

Sunday, July 12, 14:30-16:20
Doblón

Evolutionary Computation: A Unified Approach
Kenneth De Jong, George Mason University, USA

Sunday, July 12, 14:30-16:20
EscudoEvolutionary Multiobjective Optimization
Dimo Brockhoff, INRIA Lille - Nord Europe, France
Tobias Wagner, Technische Universität Dortmund, Germany

Sunday, July 12, 14:30-16:20
Comendador

Tutorials

33

Advanced Tutorials
Solving complex problems with coevolutionary algorithms
Malcolm Heywood, Dalhousie University, Canada
Krzysztof Krawiec, Poznan University of Technology, Poland

Saturday, July 11, 9:00-10:50
Patio 2

Constraint-Handling Techniques used with Evolutionary Algorithms
Carlos Coello-Coello, CINVESTAV-IPN, Mexico

Saturday, July 11, 9:00-10:50
Patio 3

Gene Regulatory Networks
Sylvain Cussat-Blanc, University of Toulouse, France
Wolfgang Banzhaf, Memorial University of Newfoundland, Canada

Saturday, July 11, 11:10-13:00
Patio 1

Parameterized Complexity Analysis of Evolutionary Algorithms
Frank Neumann, University of Adelaide, Australia
Andrew Sutton, University of Adelaide, Australia

Saturday, July 11, 14:30-16:20
Doblón

Evolutionary Algorithms for Protein Structure ModelingAmarda Shehu, George Mason University, USA
Kenneth De Jong, George Mason University, USA

Saturday, July 11, 14:30-16:20
AlcaláEvolutionary Computation for Dynamic Optimization Problems
Shengxiang Yang, De Montfort University, UK

Saturday, July 11, 16:40-18:30
DoblónBlind No More: Constant Time Non-Random Improving
Moves and Exponentially Powerful Recombination
Darrell Whitley, Colorado State University, USA

Saturday, July 11, 16:40-18:30

Generative and Developmental Systems
Kenneth Stanley, University of Central Florida, USA

Saturday, July 11, 16:40-18:30
Hidalgo

Theory of Evolution Strategies and Related Algorithms
Youhei Akimoto, Shinshu University, Japan

Saturday, July 11, 16:40-18:30
Patio 2Evolutionary Image Analysis and Signal Processing
Mengjie Zhang, University of Wellington, New ZealandStefano Cagnoni, University of Parma, Italy

Sunday, July 12, 11:10-13:00
EscudoSemantic Genetic Programming
Krzysztof Krawiec, Poznan University of Technology, Poland
Alberto Moraglio, University of Exeter, UK

Sunday, July 12, 11:10-13:00
Hidalgo

Theory of Swarm Intelligence
Dirk Sudholt, University of Sheffield, UK

Sunday, July 12, 16:40-18:30
DoblónExpressive Genetic Programming
Lee Spector, Hampshire College, USA

Sunday, July 12, 16:40-18:30
Comendador

Escudo34

Tutorials

Specialized Tutorials
Synergies between Evolutionary Algorithms and Reinforcement Learning
Madalina M. Drugan, Vrije Universiteit Brussel, Belgium

Saturday, July 11, 9:00-10:50
EscudoAutomatic (Offline) Configuration of Algorithms
Manuel López-Ibáñez, IRIDIA Laboratory, ULB, Belgium
Thomas Stützle, IRIDIA laboratory, ULB, Belgium

Saturday, July 11, 9:00-10:50
Patio 1

Medical Applications of Evolutionary Computation
Stephen Smith, University of York, UK

Saturday, July 11, 11:10-13:00
EscudoLow or no cost distributed evolutionary computationJJ Merelo, CITIC - University of Granada, Spain

Saturday, July 11, 11:10-13:00
Patio 3

Intelligent Systems for Smart Cities
Enrique Alba, University of Málaga, Spain

Sunday, July 12, 9:00-10:50
DoblónWorkshops andLate Breaking Abstracts

36Workshops and Late Breaking Abstracts

Student Workshop
Organizers: Tea Tušar, Jošef Stefan Institute
Boris Naujoks, Cologne University of Applied Sciences
Session 1
Time and Location: Saturday, July 11, 9:00-10:50, Comendador
Growing and Evolving Vibrationally Actuated Soft Robots
Benjamin Berger, Alvin Andino, Andrew Danise, John Rieffel
A Method Based on Interactive Evolutionary Computation for Increasing the Effectiveness of Advertisement
Texts
Quetzali Madera, Mario Garcı́a-Valdez, Oscar Castillo, Alejandra Mancilla
Hard Test Generation for Maximum Flow Algorithms with the Fast Crossover-Based Evolutionary Algorithm
Vladimir Mironovich, Maxim Buzdalov
An Evolutionary Algorithm for Weighted Graph Coloring Problem
Gizem Sungu, Betul Demiroz Boz
Session 2
Time and Location: Saturday, July 11, 11:10-13:00, Comendador
Differential Evolution with a Repair Method to Solve Dynamic Constrained Optimization Problems
Marı́a-Yaneli Ameca-Alducin, Efrén Mezura-Montes, Nicandro Cruz-Ramı́rez
Exploiting the relationship between structural modularity and sparsity for faster network evolution
Anton Bernatskiy, Josh C. Bongard
Selection of Auxiliary Objectives with Multi-Objective Reinforcement Learning
Arina Buzdalova, Anna Matveeva, Georgiy Korneev
A computational comparison of Memetic Differential Evolution approaches
F. Cabassi, M. Locatelli
Inferring Temporal Properties of Finite-State Machine Models with Genetic Programming
Daniil Chivilikhin, Ilya Ivanov, Anatoly Shalyto
Session 3
Time and Location: Saturday, July 11, 14:30-16:20, Comendador
Towards a knowledge base for performance data: a formal model for performance comparison.
Hans Degroote, Patrick De Causmaecker
Soft computing techniques applied to corporate and personal security
P. de las Cuevas, J.J. Merelo, P. Garcı́a-Sánchez
Evolutionary Design via Indirect Encoding of Non-Uniform Rational Basis Splines
Adam Gaier
Control of Crossed Genes Ratio for Directed Mating in Evolutionary Constrained Multi-Objective Optimization
Minami Miyakawa, Keiki Takadama, Hiroyuki Sato
A Hybrid MOGA-CSP for Multi-UAV Mission Planning
Cristian Ramirez-Atencia, Gema Bello-Orgaz, Maria D. R-Moreno, David Camacho

Workshops and Late Breaking Abstracts

37

Session 4
Time and Location: Saturday, July 11, 16:40-18:30, Comendador
Evaluation-Time Bias in Asynchronous Evolutionary Algorithms
Eric O. Scott, Kenneth A. De Jong
On the Selection of Decomposition Methods for Large Scale Fully Non-separable Problems
Yuan Sun, Michael Kirley, Saman K. Halgamuge
Symbolic Regression by Grammar-based Multi-Gene Genetic Programming
Jan Žegklitz, Petr Pošı́kStudent posters
Time and Location: Sunday, July 12, 11:10-13:00, Tapices

SecDef: Genetic and evolutionary computation in defense, security and risk management
Organizers: Frank Moore , University of Alaska Anchorage
Nur Zincir-Heywood , Dalhousie University

Session 1
Time and Location: Saturday, July 11, 11:10-13:00, Hidalgo
Coevolutionary Agent-based Network Defense Lightweight Event System (CANDLES)
George Rush, Daniel R. Tauritz, Alexander D. Kent
Using Genetic Algorithms for Deadline-Constrained Monitor Selection in Dynamic Computer Networks
Robin Mueller-Bady, Ruediger Gad, Martin Kappes, Inmaculada Medina-Bulo
A Hybrid Matheuristic Approach for Designing Reliable Wireless Multimedia Sensor Networks
Omer Ozkan, M. Ermis, I. Bekmezci

Session 2
Time and Location: Saturday, July 11, 14:30-16:20, Hidalgo
On The Identification of Specific Peer to Peer Network Applications
Can Bozdoga, Yasemin Gokcen, Ibrahim Zincir
Evolutionary Dynamic Optimization Techniques for Marine Contamination Problem
Lokman Altin, Haluk Rahmi Topcuoglu, Murat Ermis
Botnet detection system analysis on effect of botnet evolution and feature representation
Fariba Haddadi, Nur Zincir-Heywood

38Workshops and Late Breaking Abstracts

VizGEC: 6th Workshop on Visualisation Methods in Genetic and Evolutionary Computation
Organizers: David Walker, University of Exeter
Richard Everson, University of Exeter
Jonathan Fieldsend, University of Exeter
Time and Location: Saturday, July 11, 11:10-13:00, Alcalá
Spatial and Temporal Visualisation of Evolutionary Algorithm Decisions in Water Distribution Network Optimisation
Ed Keedwell, Matthew Johns, Dragan Savic
ELICIT – EvoLutIonary Computation vIsualizaTionS
Antonio Cruz
Using Particle Swarm Large-scale Optimization to Improve Color Sampling based Image Matting
Lv Liang, Huang Han, Cai Zhaoquan, Hu Hui
Visualising Multi-objective Populations with Treemaps
David J. Walker

EvoSoft: Evolutionary Computation Software Systems
Organizers: Stefan Wagner, University of Applied Sciences Upper Austria
Michael Affenzeller, University of Applied Sciences Upper Austria
Session 1
Time and Location: Saturday, July 11, 14:30-16:20, Patio 3
An Extensible JCLEC-based Solution for the Implementation of Multi-Objective Evolutionary Algorithms
Aurora Ramı́rez, José Raúl Romero, Sebastián Ventura
Redesigning the jMetal Multi-Objective Optimization Framework
Antonio J. Nebro, Juan J. Durillo, Matthieu Viegne
Simplifying Problem Definitions in the HeuristicLab Optimization Environment
Andreas Scheibenpflug, Andreas Beham, Michael Kommenda, Johannes Karder, Stefan Wagner, Michael Affenzeller
Session 2
Time and Location: Saturday, July 11, 16:40-18:30, Patio 3
AntElements: An Extensible and Scalable Ant Colony Optimization Middleware
Kamil Krynicki, Javier Jaen
Designing and Modeling a Browser-based Distributed Evolutionary Computation System
J. J. Merelo Guervós, Pablo Garcı́a-Sánchez
Deconstructing GAs into Visual Software Components
Leidy Garzón-Rodrı́guez, Henry Alberto Diosa, Sergio Rojas-Galeano

Workshops and Late Breaking Abstracts

39

ECADA: 5th Workshop on Evolutionary Computation for the Automated Design ofAlgorithms
Organizers: John Woodward, University of Stirling
Daniel Tauritz, Missouri University of Science and Technology
Manuel López-Ibáñez, Université Libre de Bruxelles
Session 1: Foundations
Time and Location: Sunday, July 12, 9:00-10:50, Comendador
A Comparison of Genetic Programming Variants for Hyper-Heuristics
Sean Harris, Travis Bueter, Daniel R. Tauritz
Learning Genetic Representations for Classes of Real-Valued Optimization Problems
Eric O. Scott, Jeffrey K. Bassett
Hyper-Heuristics: A Study On Increasing Primitive-Space
Matthew A. Martin, Daniel R. Tauritz
Session 2: Applications
Time and Location: Sunday, July 12, 11:10-13:00, Comendador
Synthesis of Parallel Iterative Sorts with Multi-Core Grammatical Evolution
Gopinath Chennupati, R. Muhammad Atif Azad, Conor Ryan
Generating Human-readable Algorithms for the Travelling Salesman Problem using Hyper-Heuristics
Patricia Ryser-Welch, Julian F. Miller, Asta Shahriar(Invited Talk) From Programs to Program Spaces: Leveraging Machine Learning and Optimisation for Automated Algorithm Design
Holger H. Hoos

Genetic Improvement
Organizers: W. B. Langdon, University College, London
David R. White, University of Glasgow
Justyna Petke, University College, London
Session 1
Time and Location: Sunday, July 12, 9:00-10:50, AlcaláIntroduction
David R. White
Rethinking Genetic Improvement ProgrammingDavid R. White, Jeremy Singer
GI4GI: Improving Genetic Improvement Fitness Functions
Mark Harman, Justyna Petke
Genetic Improvement using Higher Order Mutation

40

Workshops and Late Breaking Abstracts

Yue Jia, Fan Wu, Mark Harman, Jens Krinke
Fitness as Task-relevant Information Accumulation
Colin G. Johnson, John R. Woodward
Genetic Improvement for Software Product Lines: An Overview and a Roadmap
Roberto E. Lopez-Herrejon, Lukas Linsbauer, Wesley K. G. Assuncao
locoGP: Improving Performance by Genetic Programming Java Source Code
Brendan Cody-Kenny, Edgar Galvan-Lopez, Stephen Barrett
Removing the Kitchen Sink from Software
Jason Landsborough, Stephen Harding, Sunny Fugate
Session 2
Time and Location: Sunday, July 12, 11:10-13:00, Alcalá
Embedded Dynamic Improvement Programming
Jerry Swan, Edward Bowles, Nathan Burles, Alexander E.I. Brownlee, Zoltan A. Kocsis, Nadarajen Veerapen
Energy Optimisation via Genetic Improvement A SBSE technique for a new era in Software Development
Bobby R. Bruce
Genetic Improvement of Energy Usage is only as Reliable as the Measurements are Accurate
Saemundur O. Haraldsson, John R. Woodward
Embedding Adaptivity in Software Systems using the ECSELR framework
Kwaku Yeboah-Antw, Benoit Baudry
Evolutionary Approximation of Software for Embedded Systems: Median Function
Vojtech Mrazek, Zdenek Vasicek, Lukas Sekanina
Repairing COTS Router Firmware without Access to Source Code or Test Suites: A Case Study in Evolutionary
Software Repair
Eric Schulte, Westley Weimer, Stephanie Forrest
Grow and Graft a better CUDA pknotsRG for RNA pseudoknot free energy calculation
William B. Langdon, Mark Harman

Evolutionary Computation in Computational Structural Biology
Organizers: José Santos, University of A Coruña
Julia Handl, University of Manchester
Amarda Shehu, George Mason University
Session 1
Time and Location: Sunday, July 12, 9:00-10:50, Patio 1
MeGASS: Multi-Objective Genetic Active Site Search
Sandro Izidoro, Anisio M. Lacerda, Gisele L. Pappa
Combination of Differential Evolution and fragment-based replacements for protein structure prediction
Daniel Varela, José Santos
NK Landscape Instances Mimicking the Protein Inverse Folding Problem Towards Future Benchmarks

Workshops and Late Breaking Abstracts

41

Sune S. Nielsen, Grégoire Danoy, Pascal Bouvry, El-Ghazali Talbi

Session 2
Time and Location: Sunday, July 12, 11:10-13:00, Patio 1
Mapping Multiple Minima in Protein Energy Landscapes with Evolutionary Algorithms
Emmanuel Sapin, Kenneth A. De Jong, Amarda Shehu
An experimental analysis of the performance of side chain packing algorithms
Carlos A. Brizuela, Rosario I. Corona, Christian Lezcano, David Rodrı́guez, José D. Colbes
Using machine learning to explore the relevance of local and global features during conformational search in
Rosetta
Mario Garza Fabre, Shaun M. Kandathil, Julia Handl, Joshua Knowles, Simon Lovell

BBOB: Blackbox Optimization Benchmarking
Organizers: Youhei Akimoto, Shinshu University
Anne Auger, INRIA Saclay
Dimo Brockhoff, INRIA Lille
Nikolaus Hansen, INRIA Saclay
Olaf Mersmann, Technische Universitaet Dortmund
Petr Pošik, Czech Technical University

Session 1
Time and Location: Sunday, July 12, 9:00-10:50, Patio 3
Introduction to the BBOB Framework
Dimension Selection in Axis-Parallel Brent-STEP Method for Black-Box Optimization of Separable Continuous
FunctionsPetr Pošı́k, Petr Baudiš
Benchmarking IPOP-CMA-ES-TPA and IPOP-CMA-ES-MSR on the BBOB Noiseless Testbed
Asma Atamna

Session 2
Time and Location: Sunday, July 12, 11:10-13:00, Patio 3
Benchmarking Gaussian Processes and Random Forests Surrogate Models on the BBOB NoiselessLukáš Bajer, Zbynek Pitra, Martin Holena
The Impact of Initial Designs on the Performance of MATSuMoTo on the Noiseless BBOB-2015 Testbed: A
Preliminary Study
Dimo Brockhoff, Bernd Bischl, Tobias Wagner

42Workshops and Late Breaking Abstracts

ERML: Evolutionary Rule-based Machine Learning (former IWLCS)Organizers: Karthik Kuber, Microsoft
Masaya Nakata, The University of Electro-Communications, Japan
Kamran Shafi, University of New South Wales
Session 1: Optimization
Time and Location: Sunday, July 12, 11:10-13:00, Patio 2
A Lexicographic Multi-Objective Genetic Algorithm for Multi-Label Correlation-Based Feature Selection
Suwimol Jungjit, Alex A. Freitas
Metaheuristics based on Clustering in a Holonic Multiagent Model for the Flexible Job Shop Problem
Houssem Eddine Nouri, Olfa Belkahla Driss, Khaled Ghédira
Discovering Regression Rules with Ant Colony Optimization
James Brookhouse, Fernando E. B. Otero(Invited Talk) A Potential of Evolutionary Rule-based Machine Learning for Real World Applications
Keiki Takadama
Session 2: Learning Classifier Systems
Time and Location: Sunday, July 12, 14:30-16:20, Patio 2
A novel representation of classifier conditions named sensory tag for the XCS in multistep problems
Liang-Yu Chen, Po-Ming Lee, Tzu-Chien Hsiao
Socially Guided XCS: Using Teaching Signals to Boost Learning
Anis Najar, Olivier Sigaud, Mohamed Chetouani
Continuous Endpoint Data Mining with ExSTraCS: A Supervised Learning Classifier System
Ryan J. Urbanowicz, Niranjan Ramanand, Jason H. Moore(Invited Talk) Back to the Future: Learning Classifier Systems as Cognitive Systems
Will Browne
Session 3: Data and Spaces
Time and Location: Sunday, July 12, 16:40-18:30, Patio 2
An evolutionary missing data imputation method for pattern classification
Fabio M. F. Lobato, Vincent W. Tadaiesky, Igor M. de Araújo, Adamo L. Santana
The Relationship Between (Un)Fractured Problems and Division of Input Space
Danilo Vasconcellos Vargas, Hirotaka Takano, Junichi Murata

Semantic Methods in Genetic Programming
Organizers: Colin Johnson, University of Kent
Krzysztof Krawiec, Poznan University of Technology
Alberto Moraglio, University of Exeter
Michael ONeill, University College Dublin

Workshops and Late Breaking Abstracts

43

Session 1: Semantic-Aware Search Algorithms
Time and Location: Sunday, July 12, 14:30-16:20, Hidalgo
Greedy Semantic Local Search for Small Solutions
Robyn Ffrancon, Marc Schoenauer
Wave: Incremental Erosion of Residual Error
David Medernach, Jeannie Fitzgerald, R. Muhammad Atif Azad, Conor Ryan

Session 2: SMGP - Semantic-Aware Selection Operators
Time and Location: Sunday, July 12, 16:40-18:30, Hidalgo
Introducing Semantic-Clustering Selection in Grammatical Evolution
Stefan Forstenlechner, Miguel Nicolau, David Fagan, Michael ONeill
Comparison of Semantic-aware Selection Methods in Genetic Programming
Paweł Liskowski, Krzysztof Krawiec, Thomas Helmuth, Lee Spector

MedGEC: Medical Applications of Genetic and Evolutionary Computation
Organizers: Stephen L. Smith, University of York
Stefano Cagnoni, Universitá degli Studi di Parma
Robert M. Patton, Oak Ridge National Laboratory

Session 1: Patient Monitoring
Time and Location: Sunday, July 12, 14:30-16:20, Alcalá
Feature Set Optimization for Physical Activity Recognition using Genetic Algorithms
Alejandro Baldominos, Yago Saez, Pedro Isasi
Classification of Two-Channel Signals by Means of Genetic Programming
Daniel Rivero, Enrique Fernandez-Blanco, Julian Dorado, Alejandro Pazos
Data-Based Identification of Prediction Models for Glucosis
J. Manuel Velasco, Stephan Winkler, J. Ignacio Hidalgo, Oscar Garnica, Juan Lanchares, J. Manuel Colmenar,
Esther Maqueda, Marta Botella, Jose-Antonio Rubio

Session 2: Tools for Biomedical Data Processing
Time and Location: Sunday, July 12, 16:40-18:30, Alcalá
A Symbolic Regression Based Scoring System - Improving Peptide Identifications for MS Amanda
Viktoria Dorfer, Sergey Maltsev, Stephan Dreiseitl, Karl Mechtler, Stephan M. Winkler
The Application of Bacterial Foraging to Medical IR Image Registration

44

Workshops and Late Breaking Abstracts

Evolving Collective Behaviors in Robotics
Organizers: Abraham Prieto, University of A CoruñaNicolas Bredeche, Université Pierre et Marie Curie
Evert Haasdijk, Vrije University Amsterdam
Session 1
Time and Location: Sunday, July 12, 14:30-16:20, Patio 1
Evolution of Collective Behaviors by Minimizing Surprisal and by Micro-Macro Links
Heiko Hamann
The Cost of Communication: Environmental Pressure and Survivability in mEDEA
Andreas Steyven, Emma Hart, Ben Paechter
Embodied Evolution for Collective Indoor Surveillance and Location
Pedro Trueba, Abraham Prieto, Francisco Bellas, Richard J. Duro
Collective sharing of knowledge in a DREAM
Jacqueline Heinerman
Evolving Diverse Collective Behaviors Independent of Swarm Density
Payam Zahadat, Heiko Hamann, Thomas Schmickl
Session 2
Time and Location: Sunday, July 12, 16:40-18:30, Patio 1
Co-evolving Morphology and Behaviour for Robotic Swarms
Geoff Nitschke
Elements and current state-of-the-art of embodied evolutionary robotics
Nicolas Bredeche, Evert Haasdijk, Abraham Prieto
Simulating Morphological Evolution in Large Robot Populations
Florian Golemo, Marjeta Markovic, Jasper Schoormans, Peter de Jonge, Maik Couwenberg, Evert Haasdijk
Hyb-CCEA: Cooperative Coevolution of Hybrid Teams
Jorge Gomes, Pedro Mariano, Anders Lyhne Christensen

MetaDeeP: 2nd Workshop on Metaheuristic Design Patterns
Organizers: Chris Simons, University of the West of England
Jerry Swan, University of Stirling
Krzysztof Krawiec, Poznan University of Technology
Daniel Tauritz, Missouri University of Science and Technology
Jim Smith, University of the West of EnglandTime and Location: Sunday, July 12, 14:30-18:30, Patio 3
Metaheuristic Design Pattern: Preference
Hamzeh J. Aljawawdeh, Mohammed Odeh, Christopher L. Simons
Metaheuristic Design Pattern: Surrogate Fitness Functions

Workshops and Late Breaking Abstracts

45

Alexander E.I. Brownlee, John Woodward, Jerry Swan
The Blackboard Pattern for Metaheuristics
Kevin Graham, Jerry Swan, Simon Martin
Two-B or not Two-B? Design Patterns for Hybrid Metaheuristics
Alina Patelli, Nelly Bencomo, Anikó Ekárt, Harry Goldingay, Peter R. Lewis

Women@GECCO
Organizers: Carola Doerr, CNRS & Universite Pierre et Marie Curie
Anna Esparcia, Universitat Politècnica de València
Gabriela Ochoa, University of Stirling
Una-May O’Reilly, MIT
Nur Zincir-Heywood, Dalhousie University
Emma Hart, Edinburgh Napier University
Christine Zarges, University of Birmingham
Time and Location: Sunday, July 12, 16:40-18:30, Escudo
Introduction of Workshop and Participants(Invited talk) Lifelong Learning: An Academic & Personal Perspective
Emma Hart
Open Discussion
Science Slam: short performances of our 5 selected speakers.
Tea Tusar, Madalina Drugan, Julia Handl, Amarda Shehu, and Arina Buzdalova
Poster Session in location: Tapices

Late Breaking Abstracts
Organizer: Dirk Sudholt, University of Sheffield
Time and Location: Sunday, July 12, 11:10-13:00, Tapices
Hybridizing Genetic Algorithm with Cross Entropy for Solving Continuous Functions
Pedro Lopez-Garcia, Enrique Onieva, Eneko Osaba, Antonio D. Masegosa, Asier Perallos
An Improved Artificial Fish Swarm Algorithm in Image Segmentation application
Mingan Zhang, Yong Deng
Comparing Variable Width Backtracking and Metaheuristics, Experiments with the Maximum Diversity Problem
José-Matı́as Cutillas-Lozano, Miguel-Angel Franco, Domingo Giménez
Computational Matter: Evolving Computational Solutions in Materials
Julian Miller, Hajo Broersma
Developing Multi-Time Frame Trading Rules with a Trend Following Strategy, using GA
Jaime Machado, Rui Neves, Nuno HortaParameter-less Evolutionary Portfolio: First Experiments
José Pereira, Fernando Lobo
Various Degrees of Steadiness in NSGA-II and Their Influence on the Quality of Results
Maxim Buzdalov, Vladimir Parfenov

46Workshops and Late Breaking Abstracts

Examining The Stroop Effect using A Develomental Spatial Neuroevolution System
Amit Benbassat, Avishai Henik
A Parallel MOEA/D Generating Solutions in Minimum Overlapped Update Ranges of Solutions
Hiroyuki Sato, Minami Miyakawa, Elizabeth Pérez-Cortés
Generating Easy and Hard Problems using the Proximate Optimality Principle
John McCall, Lee Christie, Alexander Brownlee
Adaptive Evolution Control with P-I Similarity Index for Surrogate-assisted Evolutionary Computation
Taku Hasegawa, Kento Tsukada, Naoki Mori, Keinosuke Matsumoto
Malware Obfuscation through Evolutionary Packers
Marco Gaudesi, Andrea Marcelli, Ernesto Sanchez, Giovanni Squillero, Alberto Tonda
Evolutionary Approach For Minimizing Consumed Energy In a Personal Rapid Transit Transportation Systemwith a Multi-Depot Network Topology
Olfa Chebbi, Jouhaina Chaouachi
Design and Development of a Genetic Algorithm for the Distance Constrained Vehicle Routing Problem withEnvironmental Issues
Ezzeddine Fatnassi, Jouhaina Chaouachi
Rapid Evolution of Robot Gaits
Joshua Auerbach, Grégoire Heitz, Przemyslaw Kornatowski, Dario Floreano
Probabilistic Model Enhanced Genetic Algorithm for Multi-Mode Resource Constrained Project Scheduling
ProblemMayowa Ayodele, John McCall, Olivier Regnier-Coudert
A Comparative Study of Synchronization of Parallel ACO on Multi-core Processor
Shigeyoshi Tsutsui, Noriyuki Fujimoto
Evolving Self-Adaptive Tabu Search Algorithm for Storage Location Assignment Problems
Jing Xie, Yi Mei, Andy Song
Evolved Virtual Creatures with Soft-Body Muscles
Dan Lessin, Sebastian Risi
Empirical Scaling Analyser: An Automated System for Empirical Analysis of Performance Scaling
Zongxu Mu, Holger Hoos

Keynotes

Keynotes

49

GECCO Keynote

Re-designing Nature with Synthetic Biology: from Artificial Ants
and Tissues to a New Biosphere

Monday, July 13, 9:30-10:40
Auditorium + Castilla

Ricard Solé, Universitat Pompeu Fabra
As we enter the 21-st century, our potential to engineer biological systems is becoming a reality. The new field of synthetic biology, along with regenerative medicine and bioengineering
approaches allows us to modify extant organisms while we avoid evolutionary constraints.
Synthetic tissues and organs, but also new classes of tissues and even organoids have beencreated in the wet lab, and new forms of behaviour have been implemented using microbial life
forms. Synthetic multicellular life forms, synthetic swarms and biological computers are examples of this emergent field. We will review the state of the art of the area but also explore theboundaries and potential future scenarios. These involve novel, non-standard ways of processing information and performing computations in living systems but also the possibility of usingsynthetic biology as an alternative path to approach climate change and its consequences. In the future, to survive
might require to re-design nature from ourselves to the planet.
Biosketch: Ricard Solé is ICREA research professor (the Catalan Institute for research and Advanced Studies) currently working
at the Universitat Pompeu Fabra, where he leads the Complex Systems Lab located at the PRBB. He completed two full degrees inboth Physics and Biology at the University of Barcelona and received his PhD in Physics at the Polytechnic University of Catalonia
with a thesis on spatiotemporal chaos and criticality in evolutionary ecology. He was founding member of the NASA-associatedAstrobiology Centre on Madrid and is currently External Professor of the Santa Fe Institute (New Mexico, USA) as well as external
faculty of the Center for Evolution and Cancer at UCSF. He is also on the editorial board of Biology Direct and PLoS ONE.
He has been awarded with many EU grants and a James McDonnell Foundation Award and received a European Research Council
Advanced Grant (ERC 2012). He has published more than 200 papers in peer reviewed journals and his results have been featured intechnical and general publications and books. His main research interests involve the search for universal patterns of organizationin complex systems, including prebiotic replicators, cancer, multicellularity, viruses, evodevo, protocells or language to evolved
artificial objects and historical dynamics. He explores these issues using both theoretical and experimental approximations basedon synthetic biology.

GECCO Keynote

Visualising the Diversity of Benchmark Instances and Generating
New Test Instances to Elicit Insights into Algorithm Performance

Tuesday, July 14, 9:30-10:40
Auditorium + Castilla

Kate Smith-Miles, Monash University
Objective assessment of optimization algorithm performance is notoriously difficult, withconclusions often inadvertently biased towards the chosen test instances. Rather thanreporting average performance of algorithms across a set of chosen instances, we discuss a
new methodology to enable the strengths and weaknesses of different optimization algorithms
to be compared across a broader instance space. Results will be presented on various
combinatorial and continuous optimization problems to demonstrate: (i) how pockets of
the instance space can be found where algorithm performance varies significantly from theaverage performance of an algorithm; (ii) how the properties of the instances can be used to
predict algorithm performance on previously unseen instances with high accuracy; (iii) how
the relative strengths and weaknesses of each algorithm can be visualized and measured objectively; and (iv) how new
test instances can be generated to fill the instance space and provide desired insights into algorithmic power.
Biosketch: Kate Smith-Miles is a Professor in the School of Mathematical Sciences at Monash University in Australia, where
she was Head of School from 2009-2014. She currently holds a Laureate Fellowship from the Australian Research Council (20142019) to conduct research into new methodologies to gain insights into algorithm strengths and weaknesses. She is also theinaugural Director of MAXIMA (the Monash Academy for Cross & Interdisciplinary Mathematical Applications). Kate obtained
a B.Sc.(Hons) in Mathematics and a Ph.D. in Electrical Engineering, both from the University of Melbourne, Australia. She has
published 2 books on neural networks and data mining applications, and over 230 refereed journal and international conference

50

Keynotes

papers in the areas of neural networks, combinatorial optimization, intelligent systems and data mining. She has supervised tocompletion 22 PhD students, and has been awarded over AUD$12 million in competitive grants, including 11 Australian ResearchCouncil grants and industry awards. From 2007-2008 she was Chair of the IEEE Technical Committee on Data Mining (IEEE
Computational Intelligence Society). She was elected Fellow of the Institute of Engineers Australia (FIEAust) in 2006, and Fellowof the Australian Mathematical Society (FAustMS) in 2008. She was awarded the Australian Mathematical Society Medal in 2010
for distinguished research. In addition to her academic activities, she also regularly acts as a consultant to industry in the areas of
optimisation, data mining, and intelligent systems.

GECCO Keynote

Origins and Evolution of Human Language: Saltation or
Gradualism?

Wednesday, July 15, 11:10-12:10
Auditorium + Castilla

Manuel Martı́n-Loeches, Complutense University of Madrid
In the neurosciences and psycholinguistics, there are two basic views on the origin and evolution of human language. One view posits that human language in its present form emerged
around 100.000 years or less in our species, as a consequence of a single gene mutation.
These models view language as composed by a number of elements shared with other species
and therefore not exclusively human, and one single, human-specific feature: recursion, agrammatical or syntactic property by virtue of which sentences can be nested within other sentences, in a –hypothetically– unlimited fashion. The alternative perspective considers, in turn,that more than one single feature of the human language exhibits human-specific traits. Amongothers, the particular typology of the human symbols, the large amount of these that a humanbrain is able to store, or the physiological adaptations for speech articulation. Further, recursion might not be anecessary or universal feature of human language. This gradualist perspective proposes a number of possible steps
and acquisitions that would have occurred along the human lineage, by virtue of which human language, as we used it
today, is the outcome of gradual, successive stages, implying therefore multiple mutations. We will review here prosand cons- of these views, as well as how a gradualist acquisition of human language might have occurred, probably
starting much earlier than the appearance of H. sapiens some 200.000 years ago.
Biosketch: Manuel Martı́n-Loeches is full professor at the Complutense University, Madrid, where he teaches on the neuroscientific basis of human behavior and language. He is also in charge of the Cognitive Neuroscience Section at the Center for Human
Evolution and Behavior (ISCIII-UCM, Madrid, Spain) where he is leading a number of projects devoted to better understand theneural basis of human-specific behavior and cognition, such as language (syntax and semantics), religion, or art (neuroesthetics).
Other areas of research in neuroscience in which he has participated, or keeps participating, include thought disorder in schizophrenia, working memory, visual attention, the relationships between brain shape and cognition, or the interactions between emotions
and cognition. He has co-authored more than 100 scientific articles and 90 congress presentations, also regularly participating incourses and conferences on neuroscience and cognition, as well as in several newspapers, radio and TV programs, popularizing
neuroscience knowledge and perspectives to the general public. He is also the author of the book [in Spanish] Homo sapiens’ mind:
the brain and the human mind (Aguilar, 2008), and co-author with Juan Luis Arsuaga of The indelible stamp: past, present andfuture of the human being (Debate, 2013).

Humies, Competitions, andEvolutionary Computation in Practice

52

Humies, Competitions, and Evolutionary Computation in Practice

Human Competitive Results: 12th Annual Humies Awards
Presentations: Monday, July 13, 14:30-16:10
Patio 1
Announcement of Awards: Wednesday, July 15, 9:00-10:40
Auditorium + Castilla
Judging Panel: Wolfgang Banzhaf, Erik D. Goodman,
Una-May O’Reilly, Lee Spector, Darrell Whitley
Prizes: prizes totalling $10,000 to be awarded
Detailed Information: www.human-competitive.org
Techniques of genetic and evolutionary computation are being increasingly applied to difficult real-world problems —often yielding results that are not merely academically interesting, but competitive with the work done by creative andinventive humans. Starting at the Genetic and Evolutionary Computation Conference (GECCO) in 2004, cash prizes
have been awarded for human competitive results that had been produced by some form of genetic and evolutionary
computation in the previous year.
This prize competition is based on published results. The publication may be a paper at the GECCO conference(i.e., regular paper, poster paper, or any other full-length paper), a paper published anywhere in the open literature(e.g., another conference, journal, technical report, thesis, book chapter, book), or a paper in final form that has been
unconditionally accepted by a publication and is “in press” (that is, the entry must be identical to something that will
be published imminently without any further changes). The publication may not be an intermediate or draft version
that is still subject to change or revision by the authors or editors. The publication must meet the usual standardsof a scientific publication in that it must clearly describe a problem, the methods used to address the problem, theresults obtained, and sufficient information about how the work was done in order to enable the work described to be
replicated by an independent person.
Cash prizes of $5,000 (gold), $3,000 (silver), and bronze (either one prize of $2,000 or two prizes of $1,000) will beawarded for the best entries that satisfy the criteria for human-competitiveness. The awards will be divided equally
among co-authors unless the authors specify a different division at the time of submission. Prizes are paid by check in
U.S. dollars.

Humies, Competitions, and Evolutionary Computation in Practice53

Competitions
AI Controller for the Game 2048
Organizers: Wojciech Jaskowski, Marcin SzubertTime and Location: Monday, July 13, 11:10-12:50, Tapices
The goal of the competition is to learn an evaluation function for 2048. It is an addictive single-player, non-deterministic,
puzzle game that has recently taken the Internet and mobile devices by storm. One of the reasons of the game’s massive popularity is that it is very easy to learn but hard to master. The difficulty of the game together with the simplicity
of its rules makes it also an interesting testbed for computational intelligence methods. We propose the competition to
encourage comparison of different (evolutionary or not) learning algorithms and evaluation functions.

Black Box Optimization (BBComp)
Organizers: Ilya Loshchilov, Tobias Glasmachers
Time and Location: Monday, July 13, 11:10-12:50, Tapices
The Black Box Optimization Competition is the first competition in the continuous domain where test problems are
truly black boxes to participants. The only information known to the optimizer and participant is the dimension of the
problem, bounds on all variables, and a budget of black box queries. The budget ranges between 10 and 100 times
the problem dimension. It can be viewed as a common budget for expensive optimization. The competition aims at
attacking a growing impact of over-fitting of optimization algorithms to a narrow set of benchmark problems.

Combinatorial Black-Box Optimization (CBBOC)
Organizers: Brian W. Goldman, Jerry Swan, Daniel R. Tauritz
Time and Location: Monday, July 13, 11:10-12:50, Tapices
This is CBBOC’s inaugural year. It’s designed to provide the GECCO community with detailed performance comparisons of a wide variety of meta-heuristics and hyper-heuristics on combinatorial problems, where the real-world
problems which induce combinatorial problems have been categorized into those with no training time (good fit forout-of-the-box algorithms such as the Parameter-less Population Pyramid), those with short training time (good fit
for typical evolutionary algorithms), and those with long training time (good fit for hyper-heuristics). Competitors
choose which category or categories they want to submit to. The competition problems will be randomly generated bya meta-class based on NK-Landscapes.

The General Video Game AI
Organizers: Diego Perez, Spyridon Samothrakis, Julian Togelius, Tom Schaul, Simon M. Lucas
Time and Location: Monday, July 13, 11:10-12:50, Tapices
The GVG-AI Competition explores the problem of creating controllers for general video game playing. How would
you create a single agent that is able to play any game it is given? Could you program an agent that is able to play awide variety of games, without knowing which games are to be played? The Genetic and Evolutionary Computation
Conference (2015) will host the second edition of this competition, where participants will count on 30 different games
for training, a set of 10 games for validation, and a secret set of 10 test games for computing the final rankings.

54

Humies, Competitions, and Evolutionary Computation in Practice

Geometry Friends Game AI
Organizer: Rui PradaTime and Location: Monday, July 13, 11:10-12:50, Tapices
Build AI players for Geometry Friends, a 2-player cooperative platform puzzle game. These players should be able
to deal with a dynamic simulated physics environment (with gravity and friction), be capable of solving puzzles andcoordinate its actions to perform the resolution of the puzzles. Each player controls one of the two characters with
distinct capabilities: a yellow circle or a green rectangle. The circle can jump and the rectangle can change its shape.
Both characters can move horizontally. Players will need to combine the abilities of their characters in a world withplatforms to collect a set of diamonds in the least amount of time.

Industrial Challenge: Recovering missing information in heating system operating
data
Organizers: Martina Friese, Andreas Fischbach, Thomas Bartz-BeielsteinTime and Location: Monday, July 13, 14:30-16:10, Tapices
The Industrial Challenge will be held in the competition session at the Genetic and Evolutionary Computation Conference. It poses difficult real-world problems provided by industry partners from various fields. Highlights of theIndustrial Challenge include interesting problem domains, real-world data and realistic quality measurement

Simulated Car Racing Championship
Organizers: Daniele Loiacono, Frank Neumann, Mohammad Reza Bonyadi, Samadhi Nallaperuma
Time and Location: Monday, July 13, 14:30-16:10, Tapices
This long standing championship awards the enthusiasts of AI games, autonomous vehicles and car racing. In anutshell this is all about applying/comparing/creating various computational intelligence approaches to design thebest autonomous car controllers and having fun through a car racing game. The competitors are asked to design acontroller for a racing car that will compete on a set of unknown tracks first alone (against the clock) and then against
other drivers. The controllers perceive the racing environment through a number of sensors that describe the relevant
features of the car surroundings (e.g., the track limits, the position of near-by obstacles), of the car state (the fuel level,
the engine RPMs, the current gear, etc.), and the current game state (lap time, number of lap, etc.). The controller canperform the typical driving actions (clutch, changing gear, accelerate, break, steering the wheel, etc.)

The Virtual Creatures Competition
Organizers: Joel Lehman, Dan Lessin
Time and Location: Monday, July 13, 14:30-16:10, Tapices
The contest’s purpose is to highlight progress in virtual creatures research and showcase evolutionary computation’s
ability to craft interesting well-adapted creatures with evolved morphologies and controllers. Video entries demonstrating evolved virtual creatures will be judged by technical achievement, aesthetic appeal, innovation, and perceptual
animacy (perceived aliveness).

Wind Farm Layout Optimization
Organizers: Sylvain Cussat-Blanc, Dennis Wilson, Silvio Rodrigues, Kalyan Veeramachaneni
Time and Location: Monday, July 13, 14:30-16:10, Tapices
Wind farm design has long been a favored application across evolutionary computation due to its complexity, the wakecapture of a field being a difficult value to optimize analytically, and its pertinence to the world of alternative energy.
We propose the following competition to create a basis of comparison for the existing algorithms and to encourageboth new ways to solve the wind optimization problem and a new mindset for the optimization goal.

Humies, Competitions, and Evolutionary Computation in Practice55

Evolutionary Computation in Practice
Organizers: Thomas Bartz-Beielstein, Cologne University of Applied Sciences, Germany
Anna I. Esparcia-Alcázar, Universitat Politècnica de València, SpainJörn Mehnen, Cranfield University, UK
Session 1:
Bridging the gap between academia and industry

Monday, July 13, 11:10-12:50
EscudoWell-known speakers with outstanding reputation in academia and industry present background and insider information on how to establish reliable cooperation with industrial partners. If you are working in academia and are interested
in managing industrial projects, you will receive valuable hints for your own research projects.
Session 2:“Real” real-world optimization

Monday, July 13, 14:30-16:10
EscudoIn this session industry speakers will be presenting. They actually run companies in the field of optimization andapplied statistics. If you attend, you will learn multiple ways to extend EC practice beyond the approaches found in
textbooks.
Experts in real-world optimization with decades of experience share their approaches to creating successful projects
for real-world clients. Some of what they do is based on sound project management principles, and some is specificto our type of optimization projects. In this session a panel of experts describes a range of techniques you can use to
identify, design, manage, and successfully complete an EA project for a client.
Session 3:
Ask the experts / Getting a job

Monday, July 13, 16:40-18:45
EscudoThis lively session consists of a panel of experts with decades of real-world application experience answering questions
posed by attendees of the session. In the past, we have always had two or three discussions on industrial problems
that lie on the cutting edge of EA development. This session gives you the opportunity to get free consulting from theexperts!
Getting a job with training in evolutionary computation can be much easier if you know the things to do and thethings not to do in your last year or two of study. In this session you will hear from a panel of experts who havetrained students and who have hired students to carry out real-world optimization. Highly recommended if you will
be looking for a job in the next few years — or if you are thinking of changing jobs.

Papers and Posters

58

Paper Sessions, Monday, July 13, 11:10-12:50

Monday, July 13, 11:10-12:50
ACO-SI 1(Best Paper Nominees are marked with an asterisk∗ )Monday, July 13, 11:10-12:50, Patio 3
Chair: Manuel López-Ibáñez (IRIDIA, Université Libre de Bruxelles)
Evolutionary Inheritance Mechanisms for Multi-criteria Decision Making in Multi-agent Systems
Ruby Moritz, Martin Middendorf
11:10-11:35
An Ant Colony Optimization Based Memetic Algorithm for the Dynamic Travelling Salesman Problem∗
Michalis Mavrovouniotis, Felipe Müller, Shengxiang Yang
11:35-12:00
The Impact of Centrality on Individual and Collective Performance in Social Problem-Solving Systems∗
Diego Noble, Felipe Grando, Ricardo Araújo, Luis Lamb
12:00-12:25
Robustness of Ant Colony Optimization to Noise∗
Tobias Friedrich, Timo Kötzing, Martin Krejca, Andrew Sutton

12:25-12:50

AIS-AChem
Monday, July 13, 11:10-12:50, Comendador
Chair: Jonathan Timmis (University of York); Christine Zarges (The University of Birmingham)
Securing the Internet of Things with Responsive Artificial Immune Systems
Dr. Greensmith

11:10-11:35

RAIS TTP Revisited to Solve Relaxed Travel Tournament Problem
Elizabeth Montero, Maria-Cristina Riff

11:35-12:00

Distinguishing Adaptive Search from Random Search in Robots and T cells
George Fricke, Sarah Black, Joshua Hecker, Judy Cannon, Melanie Moses

12:00-12:25

An Immuno-inspired Approach Towards Sentence Generation
Samir Borgohain, Shivashankar Nair

12:25-12:50

EMO1
Monday, July 13, 11:10-12:50, Hidalgo
Chair: Carlos Henggeler Antunes (University of Coimbra)
A Study on Performance Evaluation Ability of a Modified Inverted Generational Distance Indicator
Hisao Ishibuchi, Hiroyuki Masuda, Yusuke Nojima
11:10-11:35
Characterizing Pareto Front Approximations in Many-objective Optimization
Md Asafuddoula, Tapabrata Ray, Hemant Singh

11:35-12:00

Improved Sampling of Decision Space for Pareto Estimation
Yiming Yan, Ioannis Giagkiozis, Peter Fleming

12:00-12:25

Finding the Trade-off between Robustness and Worst-case Quality
Juergen Branke, Ke Lu

12:25-12:50

Paper Sessions, Monday, July 13, 11:10-12:50

59

GA1
Monday, July 13, 11:10-12:50, Alcalá
Chair: Ernesto Costa (University of Coimbra)(Best Paper Nominees are marked with an asterisk∗ )Parasite Diversity in Symbiogenetic Multiset Genetic Algorithm - Optimization of Large Binary Problems
António Manso, Luı́s Correia
11:10-11:35
Gray-Box Optimization using the Parameter-less Population Pyramid∗
Brian Goldman, William Punch

11:35-12:00

Evolutionary Bilevel Optimization for Complex Control Tasks∗
Jason Liang, Risto Miikkulainen

12:00-12:25

Mk Landscapes, NK Landscape, MAX-kSAT∗
Darrell Whitley

12:25:12:50

GP1
Monday, July 13, 11:10-12:50, Patio 2
Chair: Lee Spector (Hampshire College)
Correlation Immunity of Boolean Functions: An Evolutionary Algorithms Perspective
Stjepan Picek, Claude Carlet, Domagoj Jakobovic, Julian Miller, Lejla Batina

11:10-11:35

Building Predictive Models via Feature Synthesis
Ignacio Arnaldo, Una-May O’Reilly, Kalyan Veeramachaneni

11:35-12:00

Impact of Crossover Bias in Genetic Programming
Nicholas McPhee, M. Dramdahl, David Donatucci

12:00-12:25

Strength Through Diversity: Disaggregation and Multi-Objectivisation Approaches for Genetic Programming
Jonathan Fieldsend, Alberto Moraglio
12:25-12:50
RWA1
Monday, July 13, 11:10-12:50, Doblón
Chair: Leonardo Trujillo (CICESE)
Genetic Programming for Estimation of Heat Flux between the Atmosphere and Sea Ice in Polar Regions
Karolina Stanislawska, Krzysztof Krawiec, Timo Vihma
11:10-11:35
On Evolutionary Approaches to Wind Turbine Placement with Geo-Constraints
Daniel Lückehe, Markus Wagner, Oliver Kramer

11:35-12:00

Efficient Sampling of PI Controllers in Evolutionary Multiobjective Optimization
Gilberto Reynoso-Meza, Leandro dos Santos Coelho, Roberto Z. Freite

12:00-12:25

Diversifying Multi-Objective Gradient Techniques and their Role in Hybrid Multi-Objective Evolutionary Algorithms for Deformable Medical Image Registration
Kleopatra Pirpinia, Tanja Alderliesten, Jan-Jakob Sonke, Marcel van Herk, Peter Bosman
12:25-12:50

60

Paper Sessions, Monday, July 13, 14:30-16:10

Monday, July 13, 14:30-16:10
ACO-SI2
Monday, July 13, 14:30-16:10, Patio 3
Chair: Leslie Pérez Caceres (IRIDIA, Université Libre de Bruxelles)
An Improved Collaborative Filtering Recommendation Algorithm Based on Community Detection in Social
Networks
Cen Cao, Qingjian Ni, Yuqing Zhai
14:30-14:55
Enhancing IACOR Local Search by Mtsls1-BFGS for Continuous Global Optimization
Udit Kumar, Jayadeva Dr, Sumit Soman

14:55-15:20

Parameter Estimation in Bayesian Networks Using Overlapping Swarm Intelligence
Nathan Fortier, John Sheppard, Shane Strasser

15:20-15:45

An Ant Colony Optimizing Algorithm Based on Scheduling Preference for Maximizing Working Time of WSN
Yu Liu, Wei-Neng Chen, Xiao-min Hu, Jun Zhang
15:45-16:10
EMO2
Monday, July 13, 14:30-16:10, Hidalgo
Chair: Heike Trautmann (University of Munster)(Best Paper Nominees are marked with an asterisk∗ )An Experimental Investigation of Variation Operators in Reference-Point Based Many-Objective Optimization∗
Yuan Yuan, Hua Xu, Bo Wang
14:30-14:55
Obtaining Optimal Pareto Front Approximations using Scalarized Preference Information∗
Marlon Braun, Pradyumn Shukla, Hartmut Schmeck

14:55-15:20∗

Benchmarking Numerical Multiobjective Optimizers Revisited
Dimo Brockhoff, Thanh-Do Tran, Nikolaus Hansen

15:20-15:45

Greedy Hypervolume Subset Selection in the Three-Objective Case∗
Andreia Guerreiro, Carlos Fonseca, Luı́s Paquete

15:45-16:10

GA2
Monday, July 13, 14:30-16:10, Alcalá
Chair: Luı́s Correia (LabMAg - Univ. Lisbon)
Maintaining 2-Approximations for the Dynamic Vertex Cover Problem Using Evolutionary Algorithms
Mojgan Pourhassan, Wanru Gao, Frank Neumann
14:30-14:55
An Empirical Analysis on Dimensionality in Cellular Genetic Algorithms
Alicia Morales-Reyes, Hugo Jair Escalante, Martin Letras, Rene Cumplido

14:55-15:20

Adaptive Control of Parameter-less Population Pyramid on the Local Distribution of Inferior Individuals
Kazuyuki Inoue, Taku Hasegawa, Yuta Araki, Naoki Mori, Keinosuke Matsumoto
15:20-15:45
A Genetic Algorithm for Searching the Shortest Lattice Vector of SVP Challenge
Dan Ding, Guizhen Zhu, Xiaoyun Wang

15:45-16:10

Paper Sessions, Monday, July 13, 14:30-16:10

61

GDS1 + PES1
Monday, July 13, 14:30-16:10, Comendador
Chair: Sebastian Risi (IT University of Copenhagen)Confronting the Challenge of Quality Diversity
Justin Pugh, L. Soros, Paul Szerlip, Kenneth Stanley

14:30-14:55

Enhancing Divergent Search through Extinction Events
Joel Lehman, Risto Miikkulainen

14:55-15:20

Devising Effective Novelty Search Algorithms: A Comprehensive Empirical Study
Jorge Gomes, Pedro Mariano, Anders Christensen

15:20-15:45

Fast Knowledge Discovery in Time Series with GPGPU on Genetic Programming
Sungjoo Ha, Byung-Ro Moon

15:45-16:10

GP2
Monday, July 13, 14:30-16:10, Patio 2
Chair: Gisele L. Pappa (Federal University of Minas Gerais)
Using Model Checking Techniques For Evaluating the Effectiveness of Evolutionary Computing in Synthesis ofDistributed Fault-Tolerant Programs
Ling Zhu, Sandeep Kulkarni
14:30-14:55
Examining the “Best of Both Worlds” of Grammatical EvolutionPeter Whigham, Grant Dick, James Maclaurin, Caitlin Owen

14:55-15:20

Performance Optimization of Multi-Core Grammatical Evolution Generated Parallel Recursive Programs
Gopinath Chennupati, R. Muhammad Azad, Conor Ryan
15:20-15:45
On the Bias of Syntactic Geometric Recombination in Genetic Programming and Grammatical Evolution
Ann Thorhauer, Franz Rothlauf
15:45-16:10
RWA2
Monday, July 13, 14:30-16:10, Doblón
Chair: Emma Hart (Napier University)(Best Paper Nominees are marked with an asterisk∗ )A Closer Look At Differential Evolution For The Optimal Well Placement Problem
Grazieli Carosio, Thomas Humphries, Ronald Haynes, Colin Farquharson

14:30-14:55

Selecting Best Investment Opportunities from Stock Portfolios Optimized by a Multiobjective Evolutionary
Algorithm∗
Krzysztof Michalak
14:55-15:20
Exploiting Linkage Information and Problem-Specific Knowledge in Evolutionary Distribution Network Expansion Planning∗
Ngoc Hoang Luong, Han La Poutré, Peter Bosman
15:20-15:45
Evolving Solutions to TSP Variants for Active Space Debris Removal∗
Dario Izzo, Ingmar Getzner, Daniel Hennes, Luı́s Simões

15:45-16:10

62

Paper Sessions, Monday, July 13, 16:40-18:45

Monday, July 13, 16:40-18:45
ALIFE1
Monday, July 13, 16:40-18:45, Hidalgo
Chair: Terence Soule (University of Idaho)
Finding a Mate With No Social Skills
Chris Marriott, Jobran Chebib

16:40-17:05

The Effect of Fitness Function Design on Performance in Evolutionary Robotics
Mohammad Divband Soorati, Heiko Hamann

17:05-17:30

Improving Survivability in Environment-driven Distributed? Evolutionary Algorithms through Explicit Relative Fitness and Fitness Proportionate Communication
Emma Hart, Andreas Steyven, Ben Paechter
17:30-17:55
An Embodied Approach for Evolving Robust Visual Classifiers
Karol Zieba, Josh Bongard
BIO1+DETA1+PES2
Monday, July 13, 16:40-18:45, Patio 1
Chair: Stefano Cagnoni (University of Parma, Italy)

17:55-18:20(Best Paper Nominees are marked with an asterisk∗ )Injection, Saturation and Feedback in Meta-Heuristic Interactions∗Krzysztof Nowak, Dario Izzo, Daniel Hennes

16:40-17:05∗

Evolutionary Optimization of Cancer Treatments in a Cancer Stem Cell Context
Ángel Monteagudo, José Santos

17:05-17:30

Solving Interleaved and Blended Sequential Decision-Making Problems through Modular Neuroevolution∗
Jacob Schrum, Risto Miikkulainen
17:30-17:55
ECOM1
Monday, July 13, 16:40-18:45, Patio 2
Chair: Hernan Aguirre (Shinshu University)
Fighting the Symmetries: The Structure of Cryptographic Boolean Function Spaces
Stjepan Picek, Robert McKay, Roberto Santana, Tom Gedeon

16:40-17:05

Towards the User Equilibrium in Traffic Assignment Using GRASP with Path Relinking
Gabriel Ramos, Ana Bazzan

17:05-17:30

A Visual Method for Analysis and Comparison of Search Landscapes
Sebastian Volke, Dirk Zeckzer, Gerik Scheuermann, Martin Middendorf

17:30-17:55

Predicting Heuristic Search Performance with PageRank Centrality in Local Optima Networks
Sebastian Herrmann, Franz Rothlauf

17:55-18:20

Guiding Evolutionary Search with Association Rules for Solving Weighted CSPs
Madalina Raschip, Cornelius Croitoru, Kilian Stoffel

18:20-18:45

Paper Sessions, Monday, July 13, 16:40-18:45

63

GA3
Monday, July 13, 16:40-18:45, Alcalá
Chair: Peter Bosman (Centrum Wiskunde & Informatica)
A Genetic Algorithm to Solve a Real 2-D Cutting Stock Problem with Setup Cost in the Paper Industry
Stephane Bonnevay, Philippe Aubertin, Gerald Gavin
16:40-17:05
A New Perspective on Channel Allocation in WLAN: Considering the Total Marginal Utility of the Connections
for the Users
Thiago Luiz, Alan Freitas, Frederico Guimarães
17:05-17:30
Reconstructing Cross-Cut Shredded Text Documents: A Genetic Algorithm with Splicing-Driven Reproduction
Yong-Feng Ge, Yue-Jiao Gong, Wei-Jie Yu, Xiao-Min Hu, Jun Zhang
17:30-17:55
A Clustering-Based Model-Building EA for Optimization Problems with Binary and Real-Valued Variables
Krzysztof Sadowski, Peter Bosman, Dirk Thierens
17:55-18:20
A Tensor Analysis Improved Genetic Algorithm for Online Bin Packing
Shahriar Asta, Ender Ozcan

18:20-18:45

HOP1: Hot Off the Press
Monday, July 13, 16:40-18:45, Comendador
Chair: Joshua Hecker (The University of New Mexico, USA)
Beyond Pheromones: Evolving Error-Tolerant, Flexible, and Scalable Ant-Inspired Robot Swarms
Joshua P. Hecker, Melanie E. Moses
16:40-17:05
Genotype Coding, Diversity, and Dynamic Evolutionary Neural Network Environments: A Study on an Multiagent System
Jaime Davila
17:05-17:30
Generalized Decomposition and Cross Entropy Methods for Many-Objective Optimization
Ioannis Giagkiozis, Robin C. Purshouse, Peter J. Fleming

17:30-17:55

Methods for Multi-Objective Optimization: An Analysis
Ioannis Giagkiozis, Peter J. Fleming

17:55-18:20

RWA3
Monday, July 13, 16:40-18:45, Doblón
Chair: Kevin Sim (Edinburgh Napier University)
Using Multi-Objective Artificial Immune Systems to Find Core Collections Based on Molecular Markers
Shana Schlottfeldt, Maria Emilia Walter, Jon Timmis, Andre Carvalho, Mariana Telles, Jose Alexandre Diniz-Filho
16:40-17:05
Smart Mobility Policies with Evolutionary Algorithms: The Adapting Info Panel Case
Daniel Stolfi, Enrique Alba

17:05-17:30

An Integrated Approach to Stage 1 Breast Cancer Detection
Jeannie Fitzgerald, Conor Ryan, David Medernach, Krzysztof Krawiec

17:30-17:55

Finding an Optimal LEGO(R) Brick Layout of Voxelized 3D Object Using a Genetic Algorithm
Sangyeop Lee, Jinhyun Kim, Jae Woo Kim, Byung-Ro Moon

17:55-18:20

64

SBSE-SS1 + EDA1 + THEORY1
Monday, July 13, 16:40-18:45, Patio 3
Chair: Gabriela Ochoa (University of Stirling)

Paper Sessions, Monday, July 13, 16:40-18:45(Best Paper Nominees are marked with an asterisk∗ )Optimal Parameter Choices Through Self-Adjustment: Applying the 1/5-th Rule in Discrete Settings
Benjamin Doerr, Carola Doerr
16:40-17:05
Random or Genetic Algorithm Search for Object-Oriented Test Suite Generation?∗
Sina Shamshiri, José Miguel Rojas, Gordon Fraser, Phil McMinn

17:05-17:30

Extracting Variability-Safe Feature Models from Source Code Dependencies in System Variants∗
Wesley Assunção, Roberto Lopez-Herrejon, Lukas Linsbauer, Silvia Vergilio, Alexander Egyed
17:30-17:55
Kernels of Mallows Models for Solving Permutation-based Problems∗
Josu Ceberio, Alexander Mendiburu, Jose Lozano

17:55-18:20

Improved Runtime Bounds for the (1+1) EA on Random 3-CNF Formulas Based on Fitness-Distance Correlation∗
Benjamin Doerr, Frank Neumann, Andrew Sutton
18:20-18:45

Paper Sessions, Tuesday, July 14, 11:10-12:50

65

Tuesday, July 14, 11:10-12:50
ACO-SI3
Tuesday, July 14, 11:10-12:50, Comendador
Chair: Andries P. Engelbrecht (University of Pretoria)
A Set-based Comprehensive Learning Particle Swarm Optimization with Decomposition for Multiobjective
Traveling Salesman Problem
Xue Yu, Wei-Neng Chen, Xiao-min Hu, Jun Zhang
11:10-11:35
The Effect of Quantum and Charged Particles on the Performance of the Dynamic Vector-evaluated Particle
Swarm Optimisation Algorithm
Marde Helbig, Andries Engelbrecht
11:35-12:00
Input-to-State Stability Analysis on Particle Swarm Optimization
Daqing Yi, Kevin Seppi, Michael Goodrich

12:00-12:25

Particle Swarm Optimization Based on Linear Assignment Problem Transformations
Luis Miguel Antonio, Carlos Artemio Coello Coello12:25-12:50

CO1(Best Paper Nominees are marked with an asterisk∗ )Tuesday, July 14, 11:10-12:50, Patio 1
Chair: Ilya Loshchilov (INRIA, University Paris-Sud)
Detecting Funnel Structures by Means of Exploratory Landscape Analysis
Pascal Kerschke, Mike Preuss, Simon Wessing, Heike Trautmann

11:10-11:35

Sample Reuse in the Covariance Matrix Adaptation Evolution Strategy Based on Importance Sampling
Shinichi Shirakawa, Youhei Akimoto, Kazuki Ouchi, Kouzou Ohara
11:35-12:00
Towards an Analysis of Self-Adaptive Evolution Strategies on the Noisy Ellipsoid Model∗
Alexander Melkozerov, Hans-Georg Beyer

12:00-12:25

Towards an Augmented Lagrangian Constraint Handling Approach for the (1+1)-ES∗
Dirk Arnold, Jeremy Porter

12:25-12:50

DETA2
Tuesday, July 14, 11:10-12:50, Patio 3
Chair: Amy K. Hoover (University of Malta)
Controlling Crowd Simulations using Neuro-Evolution
Sunrise Wang, James Gain, Geoff Nistchke

11:10-11:35

Open Loop Search for General Video Game Playing
Diego Perez Liebana, Jens Dieskau, Martin Hunermund, Sanaz Mostaghim, Simon Lucas

11:35-12:00

Darwin’s Avatars: a Novel Combination of Gameplay and Procedural Content Generation
Dan Lessin, Sebastian Risi

12:00-12:25

Interactively Evolving Compositional Sound Synthesis Networks
Björn Jónsson, Amy Hoover, Sebastian Risi

12:25-12:50

66

Paper Sessions, Tuesday, July 14, 11:10-12:50

ECOM2
Tuesday, July 14, 11:10-12:50, Doblón
Chair: Francisco Baptista Pereira (Instituto Superior de Engenharia de Coimbra)
A Genetic Algorithm for Scheduling Electric Vehicle Charging
Jorge Garcı́a-Álvarez, Miguel A. González, Camino R. Vela

11:10-11:35

A Dispatching rule based Genetic Algorithm for Order Acceptance and Scheduling
Su Nguyen, Mengjie Zhang, Tan Kay Chen

11:35-12:00

On the Impact of Local Search Operators and Variable Neighbourhood Search for the Generalized Travelling
Salesperson Problem
Mojgan Pourhassan, Frank Neumann
12:00-12:25
A Novel Diversity-based Evolutionary Algorithm for the Traveling Salesman Problem
Carlos Segura, Salvador Botello Rionda, Arturo Hernández Aguirre, S. Ivvan Valdez Peña

12:25-12:50

EMO3
Tuesday, July 14, 11:10-12:50, Hidalgo
Chair: Christian Grimme (Münster University)
Improving Robustness of Stopping Multi-objective Evolutionary Algorithms by Simultaneously Monitoring
Objective and Decision Space
Md Shahriar Mahbub, Tobias Wagner, Luigi Crema
11:10-11:35
An Approach to Mitigating Unwanted Interactions between Search Operators in Multi-Objective Optimization
Chad Byers, Betty Cheng
11:35-12:00
Fast Implementation of the Steady-State NSGA-II Algorithm for Two Dimensions Based on Incremental NonDominated Sorting
Maxim Buzdalov, Ilya Yakupov, Andrey Stankevich
12:00-12:25
A Performance Comparison Indicator for Pareto Front Approximations in Many-Objective Optimization
Miqing Li, Shengxiang Yang, Xiaohui Liu
12:25-12:50
GP3
Tuesday, July 14, 11:10-12:50, Patio 2
Chair: Nicholas Freitag McPhee (University of Minnesota, Morris)
General Program Synthesis Benchmark SuiteThomas Helmuth, Lee Spector

11:10-11:35

Improving CUDA DNA Analysis Software with Genetic Programming
William Langdon, Brian Lam, Justyna Petke, Mark Harman

11:35-12:00

Efficient Evolution of High Entropy RNGs Using Single Node Genetic Programming
Philip Leonard, David Jackson

12:00-12:25

A Re-Examination of the Use of Genetic Programming on the Oral Bioavailability Problem
Grant Dick, Aysha Rimoni, Peter Whigham

12:25-12:50

Paper Sessions, Tuesday, July 14, 11:10-12:50

67

HOP2: Hot Off the Press
Tuesday, July 14, 11:10-12:50, Escudo
Chair: Julian Miller (University of York)
Evolutionary Approach to Approximate Digital Circuits Design
Zdenek Vasicek, Lukas Sekanina

11:10-11:35

Hybrid Evolutionary Approaches to Maximum Lifetime Routing and Energy Efficiency in Sensor Mesh Networks
Alma A. M. Rahat, Richard M. Everson, Jonathan E. Fieldsend
11:35-12:00
Learning to Anticipate Flexible Choices in Multiple Criteria Decision-Making Under Uncertainty
Carlos R. B. Azevedo, Fernando J. Von Zuben
12:00-12:25
Evolving computational solutions with carbon nanotube device
Julian F. Miller, Kester D. Clegg, Maktuba Mohid

12:25-12:50

68

Paper Sessions, Tuesday, July 14, 14:30-16:10

Tuesday, July 14, 14:30-16:10
CO2
Tuesday, July 14, 14:30-16:10, Comendador
Chair: Nikolaus Hansen (INRIA-Saclay)
Dichotomy Guided Based Parameter Adaptation for Differential Evolution
Xiao-Fang Liu, Zhi-Hui Zhan, Jun Zhang

14:30-14:55

A New Repair Method For Constrained Optimization
Patrick Koch, Samineh Bagheri, Wolfgang Konen, Christophe Foussette, Peter Krause, Thomas Baeck 14:55-15:20
A Repair Method for Differential Evolution with Combined Variants to Solve Dynamic Constrained Optimization Problems
Marı́a-Yaneli Ameca-Alducin, Efrén Mezura-Montes, Nicandro Cruz-Ramı́rez
15:20-15:45
ECOM3
Tuesday, July 14, 14:30-16:10, Doblón
Chair: Carlos Cotta (University of Málaga)(Best Paper Nominees are marked with an asterisk∗ )Global vs Local Search on Multi-objective NK-Landscapes: Contrasting the Impact of Problem Features∗
Fabio Daolio, Arnaud Liefooghe, Sébastien Verel, Hernán Aguirre, Kiyoshi Tanaka
14:30-14:55
A Sequence-based Selection Hyper-heuristic Utilising a Hidden Markov Model∗
Ahmed Kheiri, Ed Keedwell

14:55-15:20

Tunnelling Crossover Networks∗
Gabriela Ochoa, Francisco Chicano, Renato Tinos, Darrell Whitley

15:20-15:45

Hyperheuristics Based on Parametrized Metaheuristic SchemesJosé-Matı́as Cutillas-Lozano, Domingo Giménez, Francisco Almeida

15:45-16:10

EMO4
Tuesday, July 14, 14:30-16:10, Hidalgo
Chair: Heike Trautmann (University of Munster)Multi-objective Optimization with Dynamic Constraints and Objectives: New Challenges for Evolutionary Algorithms
Radhia Azzouz, Slim Bechikh, Lamjed Ben Said
14:30-14:55
A New Framework for Self-adapting Control Parameters in Multi-objective Optimization
Xin Qiu, Weinan Xu, Jian-Xin Xu, Kay Chen Tan

14:55-15:20

Incorporating User Preferences in MOEA/D through the Coevolution of Weights
Martin Pilat, Roman Neruda

15:20-15:45

Empirical Study of Multi-objective Ant Colony Optimization to Software Project Scheduling Problems
Jing Xiao, Mei-Ling Gao, Min-Mei Huang
15:45-16:10

Paper Sessions, Tuesday, July 14, 14:30-16:10

69

GP4(Best Paper Nominees are marked with an asterisk∗ )Tuesday, July 14, 14:30-16:10, Patio 2
Chair: Krzysztof Krawiec (Institute of Computing Science, Poznan University of Technology) and Alberto Moraglio(University of Exeter)
Geometric Semantic Genetic Programming with Local Search
Mauro Castelli, Leonardo Trujillo, Leonardo Vanneschi, Sara Silva, Emigdio Z-Flores, Pierrick Legrand
14:55

14:30-An Efficient Structural Diversity Technique for Genetic Programming∗
Armand Burks, William Punch

14:55-15:20

Genetic Programming with Epigenetic Local Search∗
William La Cava, Thomas Helmuth, Lee Spector, Kourosh Danai

15:20-15:45

Memetic Semantic Genetic Programming∗
Robyn Ffrancon, Marc Schoenauer

15:45-16:10

HOP3: Hot Off the Press
Tuesday, July 14, 14:30-16:10, Escudo
Chair: Jason Moore (Dartmouth College)
Artificial Immune System Driven Evolution in Swarm Chemistry
Emma Hart, Nicola Capodieci, Giacomo Cabri

14:30-14:55

Incorporating Dynamism in Emergency Route Planning Problem using Immune-Based Approach
Mohd Nor Akmal Khalid, Umi Kalsom Yusof
14:55-15:20
Gene Regulatory Network Evolution Through Augmenting Topologies
Sylvain Cussat-Blanc, Kyle Harrington, Jordan Pollack

15:20-15:45

ExSTraCS 2.0: Description and Evaluation of a Scalable Learning Classifier System
Ryan Urbanowicz, Jason Moore

15:45-16:10

RWA4
Tuesday, July 14, 14:30-16:10, Patio 3
Chair: Edgar Galvan (Trinity College Dublin)
A Model with Evolutionary Covariance-based Learning for High-Frequency Financial Forecasting
Ricardo Araujo, Adriano Oliveira, Silvio Meira
14:30-14:55
Diversity Guided Evolutionary Mining of Hierarchical Process Models
Thomas Molka, David Redlich, Marc Drobek, Xiao-Jun Zeng, Wasif Gilani

14:55-15:20

A Biased Random-key Genetic Algorithm for Placement of Virtual Machines across Geo-Separated Data Centers
Fernando Stefanello, Vaneet Aggarwal, Luciana Buriol, José Gonçalves, Mauricio Resende
15:20-15:45
A Genetic Programming Approach to Cost-Sensitive Control in Resource Constrained Sensor Systems
Afsoon Yousefi Zowj, Josh Bongard, Christian Skalka
15:45-16:10

70

Paper Sessions, Tuesday, July 14, 14:30-16:10

SBSE-SS2
Tuesday, July 14, 14:30-16:10, Patio 1
Chair: Marouane Kessentini (University of Michigan)
Learning Feature-Parameter Mappings for Parameter Tuning via the Profile Expected Improvement
Jakob Bossek, Bernd Bischl, Tobias Wagner, Günter Rudolph
14:30-14:55
Operator Selection using Improved Dynamic Multi-Armed Bandit
Jany Belluz, Marco Gaudesi, Giovanni Squillero, Alberto Tonda

14:55-15:20

Reducing Energy Consumption Using Genetic Improvement
Bobby Bruce, Justyna Petke, Mark Harman

15:20-15:45

Web Service Antipatterns Detection Using Genetic Programming
Ali Ouni, Raula Gaikovina Kula, Marouane Kessentini, Katsuro Inoue

15:45-16:10

THEORY2 + EDA2
Tuesday, July 14, 14:30-16:10, Alcalá
Chair: Carola Doerr (CNRS and Univ. Sorbonne Paris 6)First Steps Towards a Runtime Comparison of Natural and Artificial Evolution
Tiago Paixao, Jorge Perez Heredia, Dirk Sudholt, Barbora Trubenova

14:30-14:55

Population Size vs. Mutation Strength for the (1+λ) EA on OneMax
Christian Giessen, Carsten Witt

14:55-15:20

Theoretical Perspective of Convergence Complexity of Evolutionary Algorithms Adopting Optimal Mixing
Yu-Fan Tung, Tian-Li Yu
15:20-15:45
Populations can be Essential in Dynamic Optimisation
Duc-Cuong Dang, Thomas Jansen, Per Kristian Lehre

15:45-16:10

Paper Sessions, Tuesday, July 14, 16:40-18:20

71

Tuesday, July 14, 16:40-18:20
ALIFE2 + GDS2
Tuesday, July 14, 16:40-18:20, Patio 1
Chair: Jean-Baptiste Mouret (ISIR - UPMC/CNRS)(Best Paper Nominees are marked with an asterisk∗ )Evolving Soft Robots in Tight Spaces
Nick Cheney, Josh Bongard, Hod Lipson

16:40-17:05

Evolving Robot Morphology Facilitates the Evolution of Neural Modularity and Evolvability
Josh Bongard, Anton Bernatskiy, Ken Livingston, Nicholas Livingston, John Long, Marc Smith

17:05-17:30∗

Novelty-Based Evolutionary Design of Morphing Underwater Robots
Francesco Corucci, Marcello Calisti, Helmut Hauser, Cecilia Laschi

17:30-17:55

Innovation Engines: Automated Creativity and Improved Stochastic Optimization via Deep Learning∗
Anh Nguyen, Jason Yosinski, Jeff Clune
17:55-18:20
BIO2+RWA5
Tuesday, July 14, 16:40-18:20, Patio 3
Chair: Mario Giacobini (University of Torino)
Evolution Strategies for Exploring Protein Energy Landscapes
Rudy Clausen, Emmanuel Sapin, Kenneth De Jong, Amarda Shehu

16:40-17:05

An Analysis of Integration of Hill Climbing in Crossover and Mutation operation for EEG Signal Classification
Arpit Bhardwaj, Aruna Tiwari, Vishaal Madaka, Ramesh Maddula
17:05-17:30
Metabolic Design And Engineering Through Ant Colony Optimization
Stephen Lincoln, Ian Rogers, Ranjan Srivastava

17:30-17:55

Evolutionary Learning of Syntax Patterns for Genic Interaction Extraction
Alberto Bartoli, Andrea De Lorenzo, Eric Medvet, Fabiano Tarlao, Marco Virgolin

17:55-18:20

ECOM4
Tuesday, July 14, 16:40-18:20, Doblón
Chair: Leonardo Vanneschi (ISEGI, Universidade Nova de Lisboa)
Minimizing Regular Objectives for Blocking Permutation Flow Shop Scheduling: Heuristic Approaches
Nouha Nouri, Talel Ladhari
16:40-17:05
Approximate Approaches to the Traveling Thief Problem
Hayden Faulkner, Sergey Polyakovskiy, Tom Schultz, Markus Wagner

17:05-17:30

On the Empirical Scaling Behaviour of State-of-the-art Local Search Algorithms for the Euclidean TSP
Jérémie Dubois-Lacoste, Holger Hoos, Thomas Stützle
17:30-17:55
Evaluation of a Multi-Objective EA on Benchmark Instances for Dynamic Routing of a Vehicle
Stephan Meisel, Christian Grimme, Jakob Bossek, Martin Wölck, Günter Rudolph, Heike Trautmann 17:55-18:20

72

EML1
Tuesday, July 14, 16:40-18:20, Comendador
Chair: Jan Koutnik (IDSIA)

Paper Sessions, Tuesday, July 14, 16:40-18:20(Best Paper Nominees are marked with an asterisk∗ )Retooling Fitness for Noisy Problems in a Supervised Michigan-style Learning Classifier System
Ryan Urbanowicz, Jason Moore
16:40-17:05
High-Dimensional Function Approximation for Knowledge-Free Reinforcement Learning: a Case Study in SZTetris
Wojciech Jaśkowski, Marcin Szubert, Paweł Liskowski, Krzysztof Krawiec
17:05-17:30
Simpler is Better: a Novel Genetic Algorithm to Induce Compact Multi-label Chain Classifiers∗
Eduardo Gonçalves, Alexandre Plastino, Alex Freitas

17:30-17:55

Subspace Clustering Using Evolvable Genome Structure∗
Sergio Peignier, Christophe Rigotti, Guillaume Beslon

17:55-18:20

EMO5
Tuesday, July 14, 16:40-18:20, Hidalgo
Chair: Carlos Henggeler Antunes (University of Coimbra)
A PSO Approach to Semivectorial Bilevel Programming: Pessimistic, Optimistic and Deceiving Solutions
Maria João Alves, Carlos Antunes, Pedro Carrasqueira
16:40-17:05
Multi-Objective BDD Optimization with Evolutionary Algorithms
Saeideh Shirinzadeh, Mathias Soeken, Rolf Drechsler

17:05-17:30

MOEA/VAN: Multiobjective Evolutionary Algorithm Based on Vector Angle Neighborhood
Roman Denysiuk, Lino Costa, Isabel Espı́rito Santo

17:30-17:55

Improved Metaheuristic Based on the R2 Indicator for Many-Objective Optimization
Raquel Hernández Gómez, Carlos Coello Coello17:55-18:20

GA4 + THEORY3
Tuesday, July 14, 16:40-18:20, Alcalá
Chair: Per Kristian Lehre (University of Nottingham)
Elitist Black-Box Models: Analyzing the Impact of Elitist Selection on the Performance of Evolutionary Algorithms
Carola Doerr, Johannes Lengler
16:40-17:05
Money for Nothing: Speeding Up Evolutionary Algorithms Through Better Initialization
Axel de Perthuis de Laillevault, Benjamin Doerr, Carola Doerr

17:05-17:30

On the Utility of Island Models in Dynamic Optimization
Andrei Lissovoi, Carsten Witt

17:30-17:55

Solving Problems with Unknown Solution Length at (Almost) No Extra Cost
Benjamin Doerr, Carola Doerr, Timo Kützing

17:55-18:20

Paper Sessions, Tuesday, July 14, 16:40-18:20

73

GP5
Tuesday, July 14, 16:40-18:20, Patio 2
Chair: William B. Langdon (University College London)
Evolutionary Image Descriptor: A Dynamic Genetic Programming Representation for Feature Extraction
Harith Al-Sahaf, Mengjie Zhang, Mark Johnston
16:40-17:05
Multiple Objective Vector-Based Genetic Programming Using Human-Derived Primitives
Jason Zutty, Daniel Long, Heyward Adams, Gisele Bennett, Christina Baxter

17:05-17:30

A GP-based Video Game Player
Baozhu Jia, Marc Ebner, Christian Schack

17:30-17:55

GEFPSO: A Framework for PSO Optimization based on Grammatical EvolutionPéricles Miranda, Ricardo Prudéncio

17:55-18:20

HOP4: Hot Off the Press
Tuesday, July 14, 16:40-18:20, Escudo
Chair: Lee Spector (Hampshire College)
The effects of asymmetric neighborhood assignment in the MOEA/D algorithm
Krzysztof Michalak

16:40-17:05

Shift-Based Density Estimation for Pareto-Based Algorithms in Many-Objective Optimization
Miqing Li, Shengxiang Yang, Xiaohui Liu

17:05-17:30

Genetic programming and serial processing for time series classification
Eva Alfaro-Cid, Ken Sharman, Anna I. Esparcia-Alcázar

17:30-17:55

Solving Uncompromising Problems with Lexicase Selection
Thomas Helmuth, Lee Spector, James Matheson

17:55-18:20

74

Paper Sessions, Wednesday, July 15, 12:25-14:05

Wednesday, July 15, 12:25-14:05
ALIFE3
Wednesday, July 15, 12:25-14:05, Patio 2
Chair: Luis Correia (BioISI, Universidade de Lisboa)
Three-fold Adaptivity in Groups of Robots: The Effect of Social Learning
Jacqueline Heinerman, Dexter Drupsteen, A.E. Eiben

12:25-12:50

Novelty Search for Soft Robotic Space Exploration
Georgios Methenitis, Daniel Hennes, Dario Izzo, Arnoud Visser

12:50-13:15

Enhancing a Model-Free Adaptive Controller through Evolutionary Computation
Anthony Clark, Philip McKinley, Xiaobo Tan

13:15-13:40

Decentralized Innovation Marking for Neural Controllers in Embodied Evolution
Iñaki Fernández Pérez, Amine Boumaza, François Charpillet

13:40-14:05

CO3
Wednesday, July 15, 12:25-14:05, Alcalá
Chair: Dirk V. Arnold (Dalhousie University)
Extended Differential Grouping for Large Scale Global Optimization with Direct and Indirect Variable Interactions
Yuan Sun, Michael Kirley, Saman Halgamuge
12:25-12:50
A CMA-ES with Multiplicative Covariance Matrix Updates
Oswin Krause, Tobias Glasmachers

12:50-13:15

Global Line Search Algorithm Hybridized with Quadratic Interpolation and Its Extension to Separable Functions
Petr Baudiš, Petr Pošı́k
13:15-13:40
EDA3
Wednesday, July 15, 12:25-14:05, Patio 1
Chairs: Pedro Larrañaga (University of the Basque Country) and Marta Soto (ICIMAF)
Optimization by Pairwise Linkage Detection, Incremental Linkage Set, and Restricted / Back Mixing: DSMGAII
Shih-Huan Hsu, Tian-Li Yu
12:25-12:50
An Estimation of Distribution Algorithm based on the Natural Gradient and the Boltzmann Distribution
Ignacio Segovia-Dominguez, Arturo Hernandez-Aguirre
12:50-13:15
Simplified Runtime Analysis of Estimation of Distribution Algorithms
Duc-Cuong Dang, Per Kristian Lehre

13:15-13:40

Paper Sessions, Wednesday, July 15, 12:25-14:05

75

EML2
Wednesday, July 15, 12:25-14:05, Comendador
Chair: Julia Handl (University of Manchester)Multiple Imputation for Missing Data Using Genetic Programming
Cao Truong Tran, Mengjie Zhang, Peter Andreae

12:25-12:50

Genetically-regulated Neuromodulation Facilitates Multi-Task Reinforcement Learning
Sylvain Cussat-Blanc, Kyle Harrington

12:50-13:15

Ant Colony and Surrogate Tree-Structured Models for Orderings-Based Bayesian Network Learning
Juan I. Alonso-Barba, Luis de la Ossa, Olivier Regnier-Coudert, John McCall, José A. Gómez, José M. Puerta
13:15-13:40
EMO6
Wednesday, July 15, 12:25-14:05, Hidalgo
Chair: Günter Rudolph (TU Dortmund)Analysis of Objectives Relationships in Multiobjective Problems Using Trade-Off Region Maps
Rodrigo Pinheiro, Dario Landa-Silva, Jason Atkin

12:25-12:50

Injecting CMA-ES into MOEA/D
Saúl Zapotecas-Martı́nez, Bilel Derbel, Arnaud Liefooghe, Dimo Brockhoff, Hernán Aguirre, Kiyoshi Tanaka
12:50-13:15
On Maintaining Diversity in MOEA/D: Application to a Biobjective Combinatorial FJSPJuan Jose Palacios, Bilel Derbel

13:15-13:40

Parallel Multi-Objective Evolutionary Design of Approximate Circuits
Radek Hrbacek

13:40-14:05

IGEC + ECOM5
Wednesday, July 15, 12:25-14:05, Doblón
Chair: Paweł Widera (Newcastle University)
Knowledge Transfer from Keepaway Soccer to Half-field Offense through Program Symbiosis: Building Simple
Programs for a Complex Task
Stephen Kelly, Malcolm Heywood
12:25-12:50
A Local Search Approach to Genetic Programming for Binary Classification
Emigdio Z-Flores, Leonardo Trujillo, Oliver Schütze, Pierrick Legrand

12:50-13:15

Evolving Strategies for Social Innovation Games
Erkin Bahceci, Riitta Katila, Risto Miikkulainen

13:15-13:40

Generator Start-up Sequences Optimization for Network Restoration Using Genetic Algorithm and Simulated
Annealing
Paul Kaufmann, Cong Shen
13:40-14:05

76

Paper Sessions, Wednesday, July 15, 12:25-14:05

SBSE-SS3
Wednesday, July 15, 12:25-14:05, Patio 3
Chair: Yuanyuan Zhang (University College London)
Heuristic Model Checking using a Monte-Carlo Tree Search Algorithm
Simon Poulding, Robert Feldt

12:25-12:50

SPRINT Multi-Objective Model Racing
Tiantian Zhang, Michael Georgiopoulos, Georgios Anagnostopoulos

12:50-13:15

Deep Parameter Optimisation
Fan Wu, Westley Weimer, Mark Harman, Yue Jia, Jens Krinke

13:15-13:40

A Hyper-Heuristic for the Multi-Objective Integration and Test Order Problem
Giovani Guizzo, Gian Fritsche, Silvia Vergilio, Aurora Pozo

13:40-14:05

THEORY4
Wednesday, July 15, 12:25-14:05, Escudo
Chair: Francisco Chicano (University of Málaga)
An Evolutionary Game Theoretic Analysis of Difference Evaluation Functions
Mitchell Colby, Kagan Tumer

12:25-12:50

On Easiest Functions for Somatic Contiguous Hypermutations And Standard Bit Mutations
Dogan Corus, Jun He, Thomas Jansen, Pietro Oliveto, Dirk Sudholt, Christine Zarges

12:50-13:15

A Tight Runtime Analysis of the (1 + (λ, λ)) Genetic Algorithm on OneMax
Benjamin Doerr, Carola Doerr

13:15-13:40

OneMax in Black-Box Models with Several Restrictions
Carola Doerr, Johannes Lengler

13:40-14:05

Poster Session

77

Poster Session
Monday, July 13, 18:45-20:45, Tapices

ACO-SI
Solving Euclidean Steiner Tree Problems with Multi Swarm Optimization
Tom Decroos, Patrick De Causmaecker, Bart Demoen
Performance Comparison of Ant Colony Algorithms for the Scheduling of Steel Production Lines
Silvino Fernández, Segundo Álvarez, Eneko Malatsetxebarria, Pablo Valledor, Diego Dı́az
Enhancing Incremental Ant Colony Algorithm for Continuous Global Optimization
Udit Kumar, Jayadeva Dr, Sumit Soman
Renumber Coevolutionary Multiswarm Particle Swarm Optimization for Multi-objective Workflow Schedulingon Cloud Computing Environment
Hai-Hao Li, Zong-Gan Chen, Zhi-Hui Zhan, Ke-Jing Du, Jun Zhang
Heuristic Search by Particle Swarm Optimization of Boolean Functions for Cryptographic Applications
Luca Mariot, Alberto Leporati
Automatic Tuning of Standard PSO Versions
Roberto Ugolotti, Stefano Cagnoni
A Dimension-Decreasing Particle Swarm Optimization Method for Portfolio Optimization
Jia-bin Wang, Wei-Neng Chen, Jun Zhang, Ying Lin
AIS-ACHEM
Grid Diversity Operator for Some Population-Based Optimization Algorithms
Ahmed Salah, Emma Hart
A Grid-facilitated AIS-based Network Scheme For Many-objective Optimization
Wilburn W. P. Tsang, Henry Y. K. Lau
ALIFE
Trading Off Resource Utilization and Task Migrations in Dynamic Load-balancing
Juan Luis Jiménez Laredo, Frédéric Guinand, Damien Olivier, Pascal Bouvry
Evolutionary Approximation of Complex Digital Circuits
Zdenek Vasicek, Lukas Sekanina
Impact of Speciation Heuristic on Crossover and Search in NEAT
Phillip Verbancsics
Crowdseeding Robot Design
Mark Wagy, Josh Bongard
CO
Investigation of Gaussian Processes and Random Forests as Surrogate Models for Evolutionary Black-Box
Optimization
Lukas Bajer, Zbynek Pitra, Martin Holena

Is Global Sensitivity Analysis Useful to Evolutionary Computation?
Thomas Chabin, Alberto Tonda, Evelyne Lutton

78

Poster Session

Infeasibility Driven Evolutionary Algorithm with the Anticipation Mechanism for the Reaching Goal in Dynamic Constrained Inverse Kinematics
Patryk Filipiak, Krzysztof Michalak, Piotr Lipinski
A Reliable and Computationally Cheap Approach for Finding Robust Optimal Solutions
Seyedali Mirjalili, Andrew Lewis
A Note on Multi-Funnel Functions for Expensive Optimization Scenario
Ryoji Tanabe
An Effective Approach for Adapting the Size of Subcomponents in Large-Scale Optimization with Cooperative
Coevolution
Giuseppe Trunfio
DETA
Estimating and Predicting Average Likability on Computer-Generated Artwork Variants
Jabier Martinez, Gabriele Rossi, Tewfik Ziadi, Tegawendé Bissyandé, Jacques Klein, Yves Le Traon
ECOM
Landscape Properties of the 0-1 Knapsack Problem
Khulood Alyahya, Jonathan Rowe
An Improved Co-evolutionary Decomposition-based Algorithm for Bi-level Combinatorial Optimization
Abir Chaabani, Slim Bechikh, Lamjed Ben Said, Radhia Azzouz
Selection Hyper-Heuristic Using a Portfolio of Derivative Heuristics
František Hruška, J. Kubalı́k
A Memetic Algorithm for Protein Structure Prediction based on Conformational Preferences of Aminoacid
Residues
Mario Inostroza-Ponta, Camilo Farfán, Márcio Dorn
Selection of Auxiliary Objectives in the Travelling Salesman Problem using Reinforcement Learning
Irina Petrova, Arina Buzdalova
An Algebraic Differential Evolution for the Linear Ordering Problem
Valentino Santucci, Marco Baioletti, Alfredo Milani
A Hybrid Particle Swarm Optimization for Solving Vehicle Routing Problem with Time Windows
Thiago Stehling, Sérgio de Souca, Moacir D.F. Filho
EDA
Herding Evolutionary Algorithm
Arnaud BernyIn Search of Optimal Linkage Trees
Roy de Bokx, Dirk Thierens, Peter Bosman
Denoising Autoencoders for Fast Combinatorial Black Box Optimization
Malte Probst
EML
Dynamically Adding Sensors to the XCS in Multistep Problems: a Sensor Tagging Approach
Liang-Yu Chen, Po-Ming Lee, Tzu-Chien Hsiao
MOGCLA: A Multi-Objective Genetic Clustering Algorithm for Large Data Analysis.
Hector David Menendez, David Camacho

Poster Session

79

Imbalanced Classification Using Genetically Optimized Random Forests
Todd Perry, Mohamed Bader-El-Den
Evolving Neurocontrollers for the Control of Information Diffusion in Social Networks
Andrew Runka, Tony White
Momentum Enhanced Neuroevolution
Gene Sher
Evolutionary Search for An Accurate Contour Segmentation in Histopathological Images
Catalin Stoean, Ruxandra Stoean, Adrian Sandita, Cristian Mesina, Corina Gruia, Daniela Ciobanu
Enable the XCS to Dynamically Learn Multiple Problems?A Sensor Tagging Approach
Yao-Ming Wu, Liang-Yu Chen, Po-Ming Lee, Tzu-Chien Hsiao
Model Selection and Overfitting in Genetic Programming: Empirical Study
Jan Žegklitz, Petr Pošı́k
EMO
Insertion of Artificial Individuals to Increase the Diversity of Multiobjective Evolutionary Algorithms
Jamisson Freitas, Cı́cero Garrozi, Mêuser Valença
A Comparative Study Use of OTL for Many-objective Optimization
Zheng Jinhua, Bai Hui, Shen Ruimin, Li Miqing
Multi-objective Optimization of Sensor Placement to Detect Contamination in Water Distribution Networks
Dolores Margarida, Carlos Antunes
Averaged Hausdorff Approximations of Pareto Fronts based on Multiobjective Estimation of Distribution Algorithms
Luis Martı́, Christian Grimme, Paskal Kerschke, Heike Trautmann, Günter Rudolph
Handling Crossover Bias to Improve Diversity in Multiobjective Evolutionary Optimization
Jean Martins, Alexandre Delbem
Fast Pareto Front Approximation for Cloud Instance Pool Optimization
Ana-Maria Oprescu, Alexandra (Vintila) Filip, Thilo Kielmann
Using Novelty-Biased GA to Sample Diversity in Graphs Satisfying Constraints
Peter Overbury, Luc Berthouze
Multi-objective NM-landscapes
Roberto Santana, Alexander Mendiburu, Jose Lozano
Dimensionality Reduction in Many-objective Problems Combining PCA and Spectral Clustering
Christian von Lücken, Hugo Monzón, Carlos Brizuela, Benjamı́n BaránComplete Multi-Objective Coverage with PaCcET
Logan Yliniemi, Kagan TumerGA
An Empirical Comparison of Genetically Evolved Programs and Evolved Neural Networks for Multi-agent
Systems Operating under Dynamic Environments
Jaime Davila

Runtime Analysis of Evolutionary Diversity Optimization and the Vertex Cover Problem
Wanru Gao, Mojgan Pourhassan, Frank Neumann

80

Poster Session

Evolving Smart Initial Layouts for Force-Directed Graph Drawing
Farshad Ghassemi Toosi, Nikola S Nikolov, Malachy Eaton
Identification of Switched Models in Non-Stationary Time Series based on Coordinate-Descent and Genetic
Algorithm
Mohammad Gorji Sefidmazgi, Mina Moradi Kordmahalleh, Abdollah Homaifar
An Adeaptive Method of Hungarian Mating Schemes in Genetic Algorithms
Chanju Jung, Yong-Hyuk Kim, Yourim Yoon, Byung-Ro Moon
When Hillclimbers Beat Genetic Algorithms in Multimodal Optimization
Fernando Lobo, Mosab Bazargani
On the Uselessness of Finite Benchmarks to Assess Evolutionaryand Swarm Methods
Pablo Rabanal, Ismael Rodrı́guez, Fernando Rubio
Pyramidal Neural Networks with Variable Receptive Fields Designed by Genetic Algorithms
Alessandra Soares, Bruno Fernandes, Carmelo Bastos-Filho
GP
Genetic C Programming with Probabilistic Evaluation
Jacqueline Christmas
Wave: A Genetic Programming Approach to Divide and Conquer
David Medernach, Jeannie Fitzgerald, R. Muhammad Atif Azad, Conor Ryan
Avoiding Overfitting in Symbolic Regression Using the First Order Derivative of GP Trees
Samaneh Sadat Mousavi Astarabadi, Mohammad Mehdi Ebadzadeh
A Single Population Genetic Programming based Ensemble Learning Approach to Job Shop SchedulingJohn Park, Su Nguyen, Mengjie Zhang, Mark Johnston
Cartesian Genetic Programming Approach for Generating Substitution Boxes of Different Sizes
Stjepan Picek, Julian Miller, Domagoj Jakobovic, Lejla Batina
Evolutionary Cross-Domain Hyper-Heuristics
Patricia Ryser-Welch, Julian Miller, Shariar Asta
Recurrent Cartesian Genetic Programming Applied to Series Forecasting
Andrew Turner, Julian Miller
The Programming Game: Evaluating MCTS as an Alternative to GP for Symbolic Regression
David White, Shin Yoo, Jeremy Singer
IGEC
A Collaborative Strategy to Reduce Initial Setup Requirements of ParamILS using EvoCa
Maria-Cristina Riff, Elizabeth Montero
PES
A Comparison Exercise on Parallel Evaluation of Rosenbrock Function
Miguel Cárdenas-Montes, Miguel Angel Vega-Rodrı́guez, Juan José Rodrı́guez-Vázquez, Antonio Gómez-Iglesias
On the Automatic Generation of Efficient Parallel Iterative Sorting Algorithms
Gopinath Chennupati, R. Muhammad Azad, Conor Ryan
Asynchronous Parallel Evolutionary Algorithms: Leveraging Heterogeneous Fitness Evaluation Times for Scalability and Elitist Parsimony Pressure
Matthew Martin, Alex Bertels, Daniel Tauritz

Poster Session

81

RWA
Grammatical Evolution for Identifying Wikipedia Taxonomies
Lourdes Araujo, Juan Martinez-Romo, Andrés DuqueA Combinatorial Genetic Algorithm for Computational Doping based Material Design
Emrah Atilgan, Jianjun Hu
Energy Efficient Allocation and Scheduling for DVFS-enabled Multicore Environments using a Multiobjective
Evolutionary Algorithm
Zorana Bankovic, Pedro López-Garcı́aVariance Reduction in Population-Based Optimization: Application to Unit Commitment
Jérémie Decock, Jialin Liu, Olivier Tetaud
Learning from Demonstration for Distributed, Encapsulated Evolution of Autonomous Outdoor Robots
Travis DeVautl, Seth Forrest, Ian Tanimoto, Terence Soule, Robert Heckendorn
Optimizing Performance of L1 Cache Memory for Embedded Systems driven by Differential Evolution
Josefa Dı́az Álvarez, J. Manuel Colmenar, José L. Risco-Martı́n, Juan Lanchares
Learning Based Control of a Fuel Cell Turbine Hybrid Power System
Andrew Gabler, Mitchell Colby, Kagan Tumer
A Multimodal Optimization and Surprise Based Consensus Community Detection Algorithm
Guanbo Jia, Shan He, Zexuan Zhu, Jing Liu, Ke Tang
Social Specialization of Space: Clustering Households on the French Riviera
Denis Pallez, Mathieu Serrurier, Célia Pereira, Giovanni Fusco, Cristina Cao
On the Model Selection of Bernoulli Restricted Boltzmann Machines Through Harmony Search
Joao Papa, Gustavo Rosa, Kelton Costa, Nilceu Marana, Walter Scheirer, David Cox
Exploiting Evolutionary Computation in an Industrial Flow for the Development of Code-Optimized Microprocessor Test Programs
Cantoro Riccardo, Marco Gaudesi, Ernesto Sanchez, Giovanni Squillero
Using Anti-pheromone to Identify Core Objects for Multidimensional Knapsack Problems: A Two-step Ants
based Approach
Nicolás Rojas, Marı́a-Cristina Riff, Elizabeth Montero
Potential-Field-Based Unit Behavior Optimization for Balancing in StarCraft II
Jonas Schmitt, Sabine Seufert, Christian Zoubek, Harald Köstler
Multi-Modal Employee Routing with Time Windows in an Urban Environment
Neil Urquhart, Emma Hart, Alistair Judson
Classifying Maritime Vessels from Satellite Imagery with HyperNEAT
Phillip Verbancsics, Josh Harguess
Software System for Container Vessel Stowage Planning using Genetic Algorithm
Miri Weiss Cohen, Adi Dahan, Izzik Kaspi
SBSE-SS
Improving Test Coverage of Formal Verification Systems via Beam Search
Mahmoud Bokhari, Markus Wagner
A Novelty Search-based Test Data Generator for Object-oriented Programs
Mohamed Boussaa, Olivier Barais, Gerson Sunye, Benoit Baudry

82

Poster Session

A Multi-objective Evolutionary Algorithm for Rule-based Performance Optimization at Software Architecture
Level
Xin Du, You Ni, Peng Ye
New Adaptive Selection Strategies for Distributed Adaptive Metaheuristic Selection
Christopher Jankee, Sébastien Verel, Bilel Derbel, Cyril Flonlupt
A Search Based Approach Towards Robust Optimization in Software Product Line Scoping
Reza Karimpour, Guenther Ruhe
A Novel Heuristic Generator for JSSP Using a Tree-Based Representation of Dispatching Rules
Kevin Sim, Emma Hart
THEORY
Criteria and Convergence Rates in Noisy Optimization
Sandra Astete-Morales, Marie-Liesse Cauwet, Olivier Teytaud
Explanation of Stagnation at Points that are not Local Optima in Particle Swarm Optimization by Potential
Analysis
Alexander Rass, Manuel Schmitt, Rolf Wanka
Efficient Sampling with Small Populations: a Genetic Algorithm Satisfying Detailed Balance
Chris Watkins, Yvonne Buttkewitz

Abstracts by Track

84

Abstracts

Ant Colony Optimization and Swarm Intelligence
ACO-SI1
Evolutionary Inheritance Mechanisms for
criteriaDecision Making in Multi-agent Systems

Multi-

Ruby Moritz, Martin Middendorf
In this paper we study the use of different evolutionary inheritance mechanisms for the adaptation of parameters in a multiagent system where the agents have to solve tasks that are distributed within a dynamic environment. In the studied system
the agents have to form teams to execute the tasks. Deciding
which task to execute next is a multi-criteria decision problem
for which the agents use different ranking schemes. Agents thathave successfully executed several tasks can reproduce and pass
the type of ranking scheme they have used and some corresponding parameter values to their successors. Three types of evolutionary mechanisms are compared: haploid, diploid, and haplodiploid. The latter one is new for multi-agent systems. The focus of our simulation experiments is to study the influence of thedifferent evolutionary mechanisms on the diversity of the agentsand on the resulting efficiency of the multi-agent system for different dynamic environments.
An Ant Colony Optimization Based Memetic Algorithm forthe Dynamic Travelling Salesman Problem
Michalis Mavrovouniotis, Felipe Müller, Shengxiang Yang
Ant colony optimization (ACO) algorithms have proved to
be able to adapt for solving dynamic optimization problems(DOPs). The integration of local search algorithms has also
proved to significantly improve the output of ACO algorithms.
However, almost all previous works consider stationary environments. In this paper, the MAX -MIN Ant System, one of the best
ACO variations, is integrated with the unstringing and stringing (US) local search operator for the dynamic travelling salesman problem (DTSP). The best solution constructed by ACO ispassed to the US operator for local search improvements. The
proposed memetic algorithm aims to combine the adaptation capabilities of ACO for DOPs and the superior performance of
the US operator on the static travelling salesman problem in order to tackle the DTSP. The experiments show that the MAX-MIN Ant System is able to provide good initial solutions to US
and the proposed algorithm outperforms other peer ACO-based
memetic algorithms on different DTSPs.
The Impact of Centrality on Individual and Collective Performance in Social Problem-Solving Systems
Diego Noble, Felipe Grando, Ricardo Araújo, Luis LambIn this paper, we analyze the dependency between centrality
and individual performance in socially-inspired problem-solving
systems. By means of extensive numerical simulations, we investigate how individual performance in four different models
correlate with four different classical centrality measures. Our
main result shows that there is a high linear correlation between
centrality and individual performance when individuals system-

atically exploit central positions. In this case, central individuals
tend to deviate from the expected majority contribution behavior. Although there is ample evidence about the relevance ofcentrality in social problem-solving, our work contributes to understand that some measures correlate better with individual performance than others due to individual traits, a position that is
gaining strength in recent studies.
Robustness of Ant Colony Optimization to Noise
Tobias Friedrich, Timo Kützing, Martin Krejca, Andrew Sutton
Recently Ant Colony Optimization (ACO) algorithms have been
proven to be efficient in uncertain environments, such as noisy or
dynamically changing fitness functions. Most of these analyses
focus on combinatorial problems, such as path finding. We analyze an ACO algorithm in a setting where we try to optimize thesimple OneMax test function, but with additive posterior noise
sampled from a Gaussian distribution. Without noise the classical (µ + 1)-EA outperforms any ACO algorithm, with smallerµ being better; however, with large noise, the (µ + 1)-EA fails,
even for high values of µ (which are known to help against small
noise). In this paper we show that ACO is able to deal with arbitrarily large noise in a graceful manner, that is, as long as theevaporation factor ρ is small enough dependent on the parameter σ 2 of the noise and the dimension n of the search space(ρ = o(1/(n(n + σ log n)2 log n))), optimization will be successful.
ACO-SI2
An Improved Collaborative Filtering Recommendation Algorithm Based on Community Detection in Social Networks
Cen Cao, Qingjian Ni, Yuqing Zhai
Recommendation algorithms in social networks have attracted
much attention in recent years. Collaborative filtering recommendation algorithm is one of the most commonly used recommendation algorithms. Traditional user-based collaborative
filtering recommendation algorithm recommends based on theuser-item rating matrix, but the large amounts of data may cause
low efficiency. In this paper, we propose an improved collaborative filtering recommendation algorithm based on community
detection. Firstly, the user-item rating matrix is mapped into theuser similarity network. Furthermore, a novel discrete particle
swarm optimization algorithm is applied to find communities in
the user similarity network, and finally Top-N items are recommend to the recommended user according to the communities.
The experiments on a real dataset validate the effectiveness ofthe proposed algorithm for improving the precision, coverage
and efficiency of recommendation.
Enhancing IACOR Local Search by Mtsls1-BFGS for Continuous Global Optimization
Udit Kumar, Jayadeva Dr, Sumit Soman

Abstracts

A widely known approach for continuous global optimization
has been the Incremental Ant Colony Framework (IACOR ).
In this paper, we propose a strategy to introduce hybridization
within the exploitation phase of the IACOR framework by using the Multi-Trajectory Local Search (Mtsls1) algorithm andBroyden-Fletcher-Goldfarb-Shanno (BFGS) algorithms. Our
approach entails making a probabilistic choice between these algorithms. In case of stagnation, we switch the algorithm being
used based on the last iteration. We evaluate our approach on
the Soft Computing (SOCO) benchmark functions and present
results by computing the mean and median errors on the global
optima achieved, as well as the iterations required. We compare
our approach with competing methods on a number of benchmark functions, and show that the proposed approach achieves
improved results. In particular, we obtain the global optima interms of average value for 14 out of 19 benchmark functions,and in terms of the median value for all SOCO benchmarks. At
the same time, the proposed approach uses fewer function evaluations on several benchmarks when compared with competing
methods, which have been found to use 54% more function evaluations.
Parameter Estimation in Bayesian Networks Using Overlapping Swarm Intelligence
Nathan Fortier, John Sheppard, Shane Strasser
Bayesian networks are probabilistic graphical models that have
proven to be able to handle uncertainty in many real-world applications. One key issue in learning Bayesian networks is parameter estimation, i.e., learning the local conditional distributionsof each variable in the model. While parameter estimation canbe performed efficiently when complete training data is available (i.e., when all variables have been observed), learning the
local distributions becomes difficult when latent (hidden) variables are introduced. While Expectation Maximization (EM) is
commonly used to perform parameter estimation in the context
of latent variables, EM is a local optimization method that often
converges to sub-optimal estimates. Although several authors
have improved upon traditional EM, few have applied population based search techniques to parameter estimation, and mostexisting population-based approaches fail to exploit the conditional independence properties of the networks. We introduce
two new methods for parameter estimation in Bayesian networks
based on particle swarm optimization (PSO). The first is a single
swarm PSO, while the second is a multi-swarm PSO algorithm.
In the multi-swarm version, a swarm is assigned to the Markov
blanket of each variable to be estimated, and competition is held
between overlapping swarms. Results of comparing these new
methods to several existing approaches indicate that the multiswarm algorithm outperforms the competing approaches whencompared using data generated from a variety of Bayesian networks.
An Ant Colony Optimizing Algorithm Based on SchedulingPreference for Maximizing Working Time of WSN
Yu Liu, Wei-Neng Chen, Xiao-min Hu, Jun Zhang

85

With the proliferation of wireless sensor networks (WSN), theissues about how to schedule all the sensors in order to maximize the systems working time have been in the spotlight. Inspired by the promising performance of ant colony optimization(ACO) in solving combinational optimization problem, we attempt to apply it in prolonging the life time of WSN. In thispaper, we propose an improved version of ACO algorithm to getsolutions about selecting exact sensors to accomplish the covering task in a reasonable way to preserve more energy to maintain longer active time. The methodology is based on maximizing the disjoint subsets of sensors, in other words, in every timeinterval, choosing which sensor to sustain active state must be
rational in certain extent. With the aid of pheromone and heuristic information, a better solution can be constructed in which
pheromone denotes the previous scheduling experience, whileheuristic information reflects the desirable device assignment.
Orderly sensor selection is designed to construct an advisable
subset for coverage task. The proposed method has been successfully applied in solving limited energy assignment problem
no matter in homogenous or heterogeneous WSNs. Simulation
experiments have shown it has a good performance in addressing
relevant issues.
ACO-SI3
A Set-based Comprehensive Learning Particle Swarm Optimization with Decomposition for Multiobjective Traveling
Salesman Problem
Xue Yu, Wei-Neng Chen, Xiao-min Hu, Jun Zhang
This paper takes the multiobjective traveling salesman problem(MOTSP) as the representative for multiobjective combinatorial problems and develop a set-based comprehensive learning
particle swarm optimization (S-CLPSO) with decomposition forsolving MOTSP. The main idea is to take advantages of both themultiobjective evolutionary algorithm based on decomposition(MOEA/D) framework and our previously proposed S-CLPSO
method for discrete optimization. Consistent to MOEA/D, amultiobjective problem is decomposed into a set of subproblems, each of which is represented as a weight vector and solved
by a particle. Thus the objective vector of a solution or the cost
vector between two cities will be transformed into real fitness to
be used in S-CLPSO for the exemplar construction, the heuristic
information generation and the update of pBest. To validate theproposed method, experiments based on TSPLIB benchmark are
conducted and the results indicate that the proposed algorithm
can improve the solution quality to some degree.
The Effect of Quantum and Charged Particles on the Performance of the Dynamic Vector-evaluated Particle Swarm
Optimisation Algorithm
Marde Helbig, Andries Engelbrecht
Many problems in the real-world have more than one objective,
with at least two objectives in conflict with one another. In addition, at least one objective changes over time. These kinds ofproblems are called dynamic multi-objective optimisation prob-

86

Abstracts

lems (DMOOPs). Studies have shown that both the quantum
particle swarm optimisation (QPSO) and charged particle swarm
optimisation (CPSO) algorithms perform well in dynamic environments, since they maintain swarm diversity. Therefore,
this paper investigates the effect of using either QPSOs or CPSOs in the sub-swarms of the dynamic vector-evaluated particle swarm optimisation (DVEPSO) algorithm. These DVEPSO
variations are then compared against the default DVEPSO algorithm that uses gbest PSOs and DVEPSO using heterogeneous PSOs that contain both charged and quantum particles.
Furthermore, all of the aforementioned DVEPSO configurations
are compared against the dynamic multi-objective optimisation(DMOPSO) algorithm that was the winning algorithm of a comprehensive comparative study of dynamic multi-objective optimisation algorithms. The results indicate that charged and quantum particles improve the performance of DVEPSO, especiallyfor DMOOPs with a deceptive POF and DMOOPs with a nonlinear POS.
Input-to-State Stability Analysis on Particle Swarm Optimization
Daqing Yi, Kevin Seppi, Michael Goodrich
This paper examines the dynamics of particle swarm optimization (PSO) by modeling PSO as a feedback cascade system andthen applying input-to-state stability analysis. Using a feedback
cascade system model we can include the effects of the globalbest and personal-best values more directly in the model of the
dynamics. Thus in contrast to previous study of PSO dynamics, the input-to-state stability property used here allows for the
analysis of PSO both before and at stagnation. In addition, theuse of input-to-state stability allows this analysis to preserve random terms which were heretofore simplified to constants. This
analysis is important because it can inform the setting of PSO

parameters and better characterize the nature of PSO as a dynamic system. This work also illuminates the way in which thepersonal-best and the global-best updates influence the bound on
the particle’s position and hence, how the algorithm exploits andexplores the fitness landscape as a function of the personal best
and global best.
Particle Swarm Optimization Based on Linear Assignment
Problem Transformations
Luis Miguel Antonio, Carlos Artemio Coello CoelloParticle swarm optimization (PSO) algorithms have been widelyused to solve a variety of optimization problems. Their successhas motivated researchers to extend the use of these techniques
to the multi-objective optimization field. However, most of these
extensions have been used to solve multi-objective optimization
problems (MOPs) with no more than three objective functions.
Here, we propose a novel multi-objective PSO (MOPSO) algorithm characterized by the use of a recent approach that transforms a MOP into a linear assignment problem (LAP), with theaim of being able to solve many-objective optimization problems. Our proposed approach, called LAP based PSO (LAPSO),
adopts the Munkres assignment algorithm to solve the generated
LAPs and has no need of an external archive. LAPSO is compared with respect to three MOPSOs which are representative of
the state-of-the-art in the area: the Optimized Multi-Objective
Particle Swarm Optimizer (OMOPSO) the Speed-constrained
Multiobjective Particle Swarm Optimizer (SMPSO) and a variant of the latter that uses the hypervolume indicator for its leader
selection scheme (SMPSOhv). Our results indicate that LAPSO
is able to outperform the MOPSOs with respect to which it wascompared in most of the test problems adopted, specially whensolving instances with more than three objectives.

Artificial Immune Systems and Artificial Chemistries
AIS-AChem
Securing the Internet of Things with Responsive Artificial
Immune Systems
Dr. Greensmith
The Internet of Things is a network of ‘smart’ objects, transforming everyday objects into entities which can measure, senseand understand their environment. The devices are uniquely
identifiable, rely on near field connectivity, often in embedded
devices. The Internet of Things is designed to be deployed
without human intervention or interaction. One application isthe ‘smart house’, with components including household appliances, networked with the user able to control devices remotely. However, the security inherent in these systems is added
as somewhat of an afterthought. One hypothetical scenario is
where a malicious party could exploit this technology with potentially disastrous consequences, turning on a cooker remotely
leading to digital arson. Reliance on standard methods is insuffi-

cient to provide the user with adequate levels of security, an area
where AIS may be extremely useful. There are currently limitations with AIS applied in security, focussing on detection without providing automatic responses. This problem provides anopportunity to advance AIS in providing both an ideal scenario
for testing their real-world application and to develop novel responsive AIS. A responsive version of the deterministic Dendritic Cell Algorithm will be proposed to demonstrate how responsive AIS will need to be developed to meet these futurechallenges through proposing the incorporation of a model ofT-cell responses.
RAIS TTP Revisited to Solve Relaxed Travel Tournament
ProblemElizabeth Montero, Maria-Cristina Riff
We are interested in methods and strategies that allow us to simplify the code of bio-inspired algorithms without altering theirAbstracts

performance. In this paper, we study an artificial immune algorithm specially designed to solve Relaxed Traveling Tournament
Problems which has been able to obtain new bounds for some instances of this problem. We use the EvoCa tuner to analyze thecomponents of the algorithm in order to discard some parts ofthe code. The results show that the filtered algorithm is able tosolve the instances as well as does the original algorithm, andwith this code we have obtained new bounds for some instancesof the problem.
Distinguishing Adaptive Search from Random Search in
Robots and T cells
George Fricke, Sarah Black, Joshua Hecker, Judy Cannon,
Melanie Moses
In order to trigger an adaptive immune response, T cells movethrough LN searching for DC that carry antigens indicative of
infection. We hypothesize that T cells adapt to cues in the LN
environment to increase search efficiency. We test this hypothesis by identifying locations that are visited by T cells more
frequently than a random model of search would suggest. We
then test whether T cells that visit such locations have different movement patterns than other T cells. Our analysis suggeststhat T cells do adapt their movement in response to cues that
may indicate the locations of DC targets. We test the ability of
our method to identify frequently visited sites in T cells and in a
swarm of simulated iAnt robots evolved to search using a suiteof biologically-inspired behaviours. We compare the movementof T cells and robots that repeatedly sample the same locationsin space with the movement of agents that do not resample spacein order to understand whether repeated sampling alters move-87

ment. Our analysis suggests that specific environmental cues
can be inferred from the movement of T cells. While the precise identity of these cues remains unknown, comparing adaptive search strategies of robots to the movement patterns of T
cells lends insights into search efficiency in both systems.
An Immuno-inspired Approach Towards Sentence Generation
Samir Borgohain, Shivashankar Nair
Though human beings comprehend, imbibe and subsequently
generate syntactically and semantically correct languages, themanner in which they do so has hardly been understood or unearthed. Most of the current work to achieve the same is heavily dependent on statistical and probabilistic data retrieved froma large corpus coupled with a formal grammar catering to theconcerned natural language. This paper attempts to portray atechnique based on an analogy described by Jerne on how his
theory of the Idiotypic Network could possibly explain the human language generation capability. Starting with a repertoireof unigrams (antibodies) weaned from a corpus available a priori, we show how these can be sequenced to generate higher
order n-grams that depict full or portions of correct sentencesin that language. These sentences or their correct portions forma network similar to the Idiotypic Network that in turn aid in
the generation of sentences or portions thereof which are new tothe corpus signifying the learning of new and correct sequences.
The network is built based on a modified version of the dynamics suggested by Farmer et. al. The paper describes the related
dynamics of the network along with the results obtained from a
corpus.

Artificial Life/Robotics/Evolvable Hardware
ALIFE1

Finding a Mate With No Social Skills
Chris Marriott, Jobran Chebib
Sexual reproductive behavior has a necessary social coordination component as willing and capable partners must both be in
the right place at the right time. While there are many known
social behavioral adaptations to support solutions to this problem, we explore the possibility and likelihood of solutions that
rely only on non-social mechanisms. We find three kinds of social organization that help solve this social coordination problem (herding, assortative mating, and natal philopatry) emerge
in populations of simulated agents with no social mechanisms
available to support these organizations. We conclude that thenon-social origins of these social organizations around sexual
reproduction may provide the environment for the developmentof social solutions to the same and different problems.

The Effect of Fitness Function Design on Performance in
Evolutionary Robotics
Mohammad Divband Soorati, Heiko Hamann
Fitness function design is known to be a critical feature of theevolutionary-robotics approach. Potentially, the complexity of
evolving a successful controller for a given task can be reduced by integrating a priori knowledge into the fitness function
which complicates the comparability of studies in evolutionary
robotics. Still, there are only few publications that study theactual effects of different fitness functions on the robot’s performance. In this paper, we follow the fitness function classification of Nelson et al. (2009) and investigate a selection offour classes of fitness functions that require different degrees ofa priori knowledge. The robot controllers are evolved in simulation using NEAT and we investigate different tasks including obstacle avoidance and (periodic) goal homing. The best
evolved controllers were then post-evaluated by examining theirpotential for adaptation, determining their convergence rates,
and using cross-comparisons based on the different fitness function classes. The results confirm that the integration of more a88

Abstractspriori knowledge can simplify a task and show that more attention should be paid to fitness function classes when comparing
different studies.
Improving Survivability in Environment-driven Distributed? Evolutionary Algorithms through Explicit Relative Fitness and Fitness Proportionate Communication
Emma Hart, Andreas Steyven, Ben Paechter
Ensuring the integrity of a robot swarm in terms of maintaining a? stable population of functioning robots over long periods of time is a mandatory prerequisite for building more complex systems that? achieve user-defined tasks. mEDEA isan environment-driven? evolutionary algorithm that provides
promising results using an? implicit fitness function combinedwith a random genome selection? operator. Motivated by theneed to sustain a large population with sufficient spare energy
to carry out user-defined tasks in the? future, we develop an
explicit fitness metric providing a measure of? fitness that is
relative to surrounding robots and examine two? methods bywhich it can influence spread of genomes. Experimental resultsin simulation find that use of the fitness-function provides significant improvements over the original algorithm; in particular, amethod that influences the frequency and range of broadcasting?
when combined with random selection has the potential to conserve? energy whilst maintaining performance, a critical factor
for? physical robots.
An Embodied Approach for Evolving Robust Visual Classifiers
Karol Zieba, Josh Bongard
Despite recent demonstrations that deep learning methods can
successfully recognize and categorize objects using high dimensional visual input, other recent work has shown that these methods can fail when presented with novel input. However, a robotthat is free to interact with objects should be able to reduce spurious differences between objects belonging to the same classthrough motion and thus reduce the likelihood of overfitting.
Here we demonstrate a robot that achieves more robust categorization when it evolves to use proprioceptive sensors and isthen trained to rely increasingly on vision, compared to a similar
robot that is trained to categorize only with visual sensors. This
work thus suggests that embodied methods may help scaffold
the eventual achievement of robust visual classification.
ALIFE2Evolving Robot Morphology Facilitates the Evolution of
Neural Modularity and Evolvability
Josh Bongard, Anton Bernatskiy, Ken Livingston, Nicholas Livingston, John Long, Marc Smith
Although recent work has demonstrated that modularity can increase evolvability in non-embodied systems, it remains to be
seen how the morphologies of embodied agents influences theability of an evolutionary algorithm to find useful and modular controllers for them. We hypothesize that a modular control

system may enable different parts of a robot’s body to sense andreact to stimuli independently, enabling it to correctly recognize
a seemingly novel environment as, in fact, a composition of familiar percepts and thus respond appropriately without need offurther evolution. Here we provide evidence that supports thishypothesis: We found that such robots can indeed be evolved if(1) the robot’s morphology is evolved along with its controller,(2) the fitness function selects for the desired behavior and (3)also selects for conservative and robust behavior. In addition, weshow that if constraints (1) and (3) are relaxed, or structural modularity is selected for directly, the robots have too little or too
much modularity and lower evolvability. Thus, we demonstrate
a previously unknown relationship between modularity and embodied cognition: evolving morphology and control such thatrobots exhibit conservative behavior indirectly selects for appropriate modularity and, thus, increased evolvability.
Novelty-Based Evolutionary Design of Morphing Underwater Robots
Francesco Corucci, Marcello Calisti, Helmut Hauser, Cecilia
LaschiRecent developments in robotics demonstrated that bioinspiration and embodiement are powerful tools to achieve robust behavior in presence of little control. In this context morphological design is usually performed by humans, following a set ofheuristic principles: in general this can be limiting, both from anengineering and an artificial life perspectives. In this work wethus suggest a different approach, leveraging evolutionary techniques. The case study is the one of improving the locomotion
capabilities of an existing bioinspired robot. First, we explore
the behavior space of the robot to discover a number of qualitatively different morphology-enabled behaviors, from whose
analysis design indications are gained. The suitability of novelty search – a recent open-ended evolutionary algorithm – forthis intended purpose is demonstrated. Second, we show how
it is possible to condense such behaviors into a reconfigurable
robot capable of online morphological adaptation (morphosis,
morphing). Examples of successful morphing are demonstrated,
in which changing just one morphological parameter entails adramatic change in the behavior: this is promising for a future robot design. The approach here adopted represents a novel
computed-aided, bioinspired, design paradigm, merging humanand artificial creativity. This may result in interesting implications also for artificial life, having the potential to contribute in
exploring underwater locomotion ”as-it-could-be”.
ALIFE3Three-fold Adaptivity in Groups of Robots: The Effect ofSocial Learning
Jacqueline Heinerman, Dexter Drupsteen, A.E. Eiben
Adapting the control systems of robots on the fly is importantin robotic systems of the future. In this paper we present andinvestigate a three-fold adaptive system based on evolution, individual and social learning in a group of robots and report on a

Abstracts

proof-of-concept study based on e-pucks. We distinguish inheritable and learnable components in the robots’ makeup, specify
and implement operators for evolution, learning and social learning, and test the system in an arena where the task is to learn
to avoid obstacles. In particular, we make the sensory layout
evolvable, the locomotion control system learnable and investigate the effects of including social learning in the ‘adaptationengine’. Our simulation experiments demonstrate that the fullmix of three adaptive mechanisms is practicable and that adding
social learning leads to better controllers faster.
Novelty Search for Soft Robotic Space Exploration
Georgios Methenitis, Daniel Hennes, Dario Izzo, Arnoud Visser
The use of soft robots in future space exploration is still a farfetched idea, but an attractive one. Soft robots are inherently
compliant mechanisms that are well suited for locomotion onrough terrain as often faced in extra-planetary environments.
Depending on the particular application and requirements, thebest shape (or body morphology) and locomotion strategy forsuch robots will vary substantially. Recent developments in soft
robotics and evolutionary optimization showed the possibility tosimultaneously evolve the morphology and locomotion strategy
in simulated trials. The use of techniques such as generative encoding and neural evolution were key to these findings. In thispaper, we improve further on this methodology by introducing
the use of a novelty measure during the evolution process. We
compare fitness search and novelty search in different gravity
levels and we consistently find novelty-based search to perform
as good as or better than a fitness–based search, while also delivering a greater variety of designs. We propose a combinationof the two techniques using fitness-elitism in novelty search toobtain a further improvement. We then use our methodology to
evolve the gait and morphology of soft robots at different gravity
levels, finding a taxonomy of possible locomotion strategies thatare analyzed in the context of space-exploration.
Enhancing a Model-Free Adaptive Controller through Evolutionary Computation
Anthony Clark, Philip McKinley, Xiaobo Tan

89

Many robotic systems experience fluctuating dynamics during
their lifetime. Variations can be attributed in part to material
degradation and decay of mechanical hardware. One approachto mitigating these problems is to utilize an adaptive controller.
For example, in model-free adaptive control (MFAC) a controller learns how to drive a system by continually updating linkweights of an artificial neural network (ANN). However, determining the optimal control parameters for MFAC, including thestructure of the underlying ANN, is a challenging process. In
this paper we investigate how to enhance the online adaptability of MFAC-based systems through computational evolution.
We apply the proposed methods to a simulated robotic fish propelled by a flexible caudal fin. Results demonstrate that the robot
is able to effectively respond to changing fin characteristics andvarying control signals when using an evolved MFAC controller.
Notably, the system is able to adapt to characteristics not encountered during evolution. The proposed technique is generaland can be applied to improve the adaptability of other cyberphysical systems.
Decentralized Innovation Marking for Neural Controllers in
Embodied Evolution
Iñaki Fernández Pérez, Amine Boumaza, François Charpillet
We propose a novel innovation marking method for NeuroEvolution of Augmenting Topologies in Embodied Evolutionary Robotics. This method does not rely on a centralized clock,which makes it well suited for the decentralized nature of EE
where no central evolutionary process governs the adaptation ofa team of robots exchanging messages locally. This method is
inspired from event dating algorithms, based on logical clocks,
that are used in distributed systems, where clock synchronization is not possible. We compare our method to odNEAT, analgorithm in which agents use local time clocks as innovation
numbers, on two multi-robot learning tasks: navigation and item
collection. Our experiments showed that the proposed method
performs as well as odNEAT, with the added benefit that it does
not rely on synchronization of clocks and is not affected by time
drifts.

Biological and Biomedical Applications
BIO1
Evolutionary Optimization of Cancer Treatments in a Cancer Stem Cell Context
Ángel Monteagudo, José Santos
We used evolutionary computing for optimizing cancer treatments taking into account the presence and effects of cancer
stem cells. We used a cellular automaton to model tumor growthat cellular level, based on the presence of the main cancer hallmarks in the cells. The cellular automaton allows the study ofthe emergent behavior of the multicellular system evolution indifferent scenarios defined by the predominance of the differ-

ent hallmarks. When cancer stem cells (CSCs) are modeled, themulticellular system evolution is additionally dependent on the
CSC tumor regrowth capability because their differentiation to
non-stem cancer cells. When a standard treatment is applied
against non-stem (differentiated) cancer cells, different effects
are present depending on the strategy used to eliminate these
non-stem cancer cells. We used Differential Evolution to optimize the treatment application strategy in terms of intensity,
duration and periodicity to minimize the final outcome of tumor
growth and regrowth.

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Abstracts

BIO2
Evolution Strategies for Exploring Protein Energy Landscapes
Rudy Clausen, Emmanuel Sapin, Kenneth De Jong, Amarda
Shehu
The focus on important diseases of our time has prompted many
experimental labs to resolve and deposit functional structures of
disease-causing or disease-participating proteins. At this point,
many functional structures of wildtype and disease-involved
variants of a protein exist in structural databases. The objective
for computational approaches is to employ such information to
discover features of the underlying energy landscape on whichfunctional structures reside. Important questions about which
subset of structures are most thermodynamically-stable remainunanswered. The challenge is how to transform an essentiallydiscrete problem into one where continuous optimization is suitable and effective. In this paper, we present such a transformation, which allows adapting and applying evolution strategies to
explore an underlying continuous variable space and locate theglobal optimum of a multimodal fitness landscape. The paper
presents results on wildtype and mutant sequences of proteins
implicated in human disorders, such as cancer and Amyotrophic
lateral sclerosis. More generally, the paper offers a methodology for transforming a discrete problem into a continuous optimization one as a way to possibly address outstanding discrete
problems in the evolutionary computation community.
An Analysis of Integration of Hill Climbing in Crossover andMutation operation for EEG Signal Classification
Arpit Bhardwaj, Aruna Tiwari, Vishaal Madaka, Ramesh Maddula
A common problem in the diagnosis of epilepsy is the volatileand unpredictable nature of the epileptic seizures. Hence, it isessential to develop Automatic seizure detection methods. Genetic programming (GP) has a potential for accurately predicting a seizure in an EEG signal. However, the destructive natureof crossover operator in GP decreases the accuracy of predict-ing the onset of a seizure. Designing constructive crossover andmutation operators (CCM) and integrating local hill climbing
search technique with the GP have been put forward as solutions. In this paper, we proposed a hybrid crossover and mutation operator, which uses both the standard GP and CCM-GP, tochoose high performing individuals in the least possible time. To
demonstrate our approach, we tested it on a benchmark EEG signal dataset. We also compared and analyzed the proposed hybrid
crossover and mutation operation with the other state of art GP
methods in terms of accuracy and training time. Our method has
shown remarkable classification results. These results affirm thepotential use of our method for accurately predicting epileptic
seizures in an EEG signal and hint on the possibility of building
a real time automatic seizure detection system.
Metabolic Design And Engineering Through Ant Colony
Optimization
Stephen Lincoln, Ian Rogers, Ranjan Srivastava
Due to the vast search space of all possible combinations of reaction knockouts in Escherichia coli, determining the best combination of knockouts for over-production of a metabolite of interest is a computationally expensive task. Ant colony optimization (ACO) applied to genome-scale metabolic models via flux
balance analysis (FBA) provides a means by which such a solution space may feasibly be explored. In previous work, theMinimization of Metabolic Adjustment (MoMA) objective function for FBA was used in conjunction with ACO to identify thebest gene knockouts for succinic acid production. In this work,
algorithmic and biological constraints are introduced to further
reduce the solution space. We introduce Stochastic Exploration
Edge Reduction Ant Colony Optimization, or STEER-ACO. Algorithmically, ACO is modified to refine its search space overtime allowing for greater initial coverage of the solution space
while ultimately honing on a high quality solution. Biologically, a heuristic is introduced allowing the maximum numberof knockouts to be no greater than five. Beyond this number,cellular viability becomes suspect. Results using this approachversus previous methods are reported.

Continuous Optimization
CO1
Detecting Funnel Structures by Means of Exploratory Landscape Analysis
Pascal Kerschke, Mike Preuss, Simon Wessing, Heike Trautmann
In single-objective optimization different optimization strategies
exist depending on the structure and characteristics of the underlying problem. In particular, the presence of so-called funnels in multimodal problems offers the possibility of applying
techniques exploiting the global structure of the function. The
recently proposed Exploratory Landscape Analysis approach automatically identifies problem characteristics based on a moder-ately small initial sample of the objective function and proved
to be effective for algorithm selection problems in continuous
black-box optimization. In this paper, specific features for detecting funnel structures are introduced and combined with theexisting ones in order to classify optimization problems regarding the funnel property. The effectiveness of the approach isshown by experiments on specifically generated test instancesand validation experiments on standard benchmark problems.

Abstracts

Sample Reuse in the Covariance Matrix Adaptation Evolution Strategy Based on Importance Sampling
Shinichi Shirakawa, Youhei Akimoto, Kazuki Ouchi, Kouzou
Ohara
Recent studies reveal that the covariance matrix adaptation evolution strategy (CMA-ES) updates the parameters based on thenatural gradient. The rank-based weight is considered the resultof the quantile-based transformation of the objective value andthe parameters are adjusted in the direction of the natural gradient estimated by Monte-Carlo with the samples drawn from thecurrent distribution. In this paper, we propose a sample reusemechanism for the CMA-ES. On the basis of the importancesampling, the past samples are reused to reduce the estimation
variance of the quantile and the natural gradient. We derive theformula for the rank-mu update of the covariance matrix andthe mean vector update using the past samples, then incorporate
it into the CMA-ES without the step-size adaptation. From thenumerical experiments, we observe that the proposed approachhelps to reduce the number of function evaluations on many
benchmark functions, especially when the number of samples
at each iteration is relatively small.
Towards an Analysis of Self-Adaptive Evolution Strategies
on the Noisy Ellipsoid Model:
Alexander Melkozerov, Hans-Georg Beyer
This paper analyzes the multi-recombinant self-adaptive evolution strategy (ES), denoted as (µ/µI , λ)-σSA-ES on the convexquadratic function class under the influence of noise, whichis referred to as noisy ellipsoid model. Asymptotically exact
progress rate and self-adaptation response measures are derived(i.e., for N → ∞, N - search space dimensionality) for the considered objective function model and verified using experimental
ES runs.
Towards an Augmented Lagrangian Constraint Handling
Approach for the (1+1)-ES
Dirk Arnold, Jeremy Porter
We consider the problem of devising an approach for handlinginequality constraints in evolution strategies that allows converging linearly to optimal solutions on sphere functions with a single linear constraint. An analysis of the single-step behaviour ofthe (1+1)-ES shows that the task of balancing improvements inthe objective with those in the constraint function is quite delicate, and that adaptive approaches need to be carefully designed
in order to avoid failure. Based on the understanding gained,
we propose a simple augmented Lagrangian approach and experimentally demonstrate good performance on a broad range of
sphere functions as well as on moderately ill-conditioned ellipsoids with a single linear constraint.

91

CO2
Dichotomy Guided Based Parameter Adaptation for Differential Evolution
Xiao-Fang Liu, Zhi-Hui Zhan, Jun Zhang
Differential evolution (DE) is an efficient and powerful
population-based stochastic evolutionary algorithm, which
evolves according to the differential between individuals. The
success of DE in obtaining the optima of a specific problem depends greatly on the choice of mutation strategies and control
parameter values. Good parameters lead the individuals towards
optima successfully. The increasing of the success rate (the ratio of entering the next generation successfully) of population
can speed up the searching. Adaptive DE incorporates successhistory or population-state based parameter adaptation. However, sometimes poor parameters may improve individual withsmall probability and are regarded as successful parameters. The
poor parameters may mislead the parameter control. So, in thispaper, we propose a novel approach to distinguish between goodand poor parameters in successful parameters. In order to speed
up the convergence of algorithm and find more good parameters,
we propose a dichotomy adaptive DE (DADE), in which the successful parameters are divided into two parts and only the partwith higher success rate is used for parameter adaptation control.
Simulation results show that DADE is competitive to other classic or adaptive DE algorithms on a set of benchmark problem
and IEEE CEC 2014 test suite.

A New Repair Method For Constrained Optimization
Patrick Koch, Samineh Bagheri, Wolfgang Konen, Christophe
Foussette, Peter Krause, Thomas Baeck
Nowadays, constraints play an important role in industry, because most industrial optimization tasks underly several restrictions. Finding good solutions for a particular problem with respect to all constraint functions can be expensive, especiallywhen the dimensionality of the search space is large and many
constraint functions are involved. Unfortunately function evaluations in industrial optimization are heavily limited, because
often expensive simulations must be conducted. For such highdimensional optimization tasks, the constraint optimization algorithm COBRA was proposed, making use of surrogate modeling for both the objective and the constraint functions. In thispaper we present a new mechanism for COBRA to repair infill
solutions with slightly violated constraints. The repair mechanism is based on gradient descent on surrogates of the constraintfunctions and aims at finding nearby feasible solutions. We test
the repair mechanism on a real-world problem from the automotive industry and on other synthetic test cases. It is shown inthis paper that with the integration of the repair method, the percentage of infeasible solutions is significantly reduced, leading
to faster convergence and better final results.

92

Abstracts

A Repair Method for Differential Evolution with Combined
Variants to Solve Dynamic Constrained Optimization Problems
Marı́a-Yaneli Ameca-Alducin, Efrén Mezura-Montes, Nicandro
Cruz-Ramı́rez
Repair methods, which usually require feasible solutions as reference, have been employed by Evolutionary Algorithms tosolve constrained optimization problems. In this work, a novel
repair method, which does not require feasible solutions as reference and inspired by the differential mutation, is added to an algorithm which uses two variants of differential evolution to solve
dynamic constrained optimization problems. The proposed repair method replaces a local search operator with the aim to improve the overall performance of the algorithm in different frequencies of change in the constrained space. The proposed approach is compared against other recently proposed algorithms
in an also recently proposed benchmark. The results show thatthe proposed improved algorithm outperforms its original version and provides a very competitive overall performance withdifferent change frequencies.

functions investigated. Significantly, when our decomposition
method is embedded in the cooperative co-evolution framework,
it achieves comparable or better solution quality than the differential grouping method.
A CMA-ES with Multiplicative Covariance Matrix Updates
Oswin Krause, Tobias Glasmachers
Covariance matrix adaptation (CMA) mechanisms are corebuilding blocks of modern evolution strategies. Despite sharing
a common principle, the exact implementation of CMA varies
considerably between different algorithms. In this paper, we investigate the benefits of an exponential parametrization of thecovariance matrix in the CMA-ES. This technique was first proposed for the xNES algorithm. It results in a multiplicative update formula for the covariance matrix. We show that the exponential parameterization and the multiplicative update are compatible with all mechanisms of CMA-ES. The resulting algorithm, xCMA-ES, performs at least on par with plain CMA-ES.
Its advantages show in particular with updates that actively decrease the sampling variance in specific directions, i.e., for active
constraint handling.

CO3
Extended Differential Grouping for Large Scale Global Optimization with Direct and Indirect Variable Interactions
Yuan Sun, Michael Kirley, Saman Halgamuge
Cooperative co-evolution is a framework that can be used toeffectively solve large scale optimization problems. This approach employs a divide and conquer strategy, which decomposes the problem into sub-components that are optimized separately. However, solution quality relies heavily on the decomposition method used. Ideally, the interacting decision variables
should be assigned to the same sub-component and the interdependency between sub-components should be kept to a minimum. Differential grouping, a recently proposed method, hashigh decomposition accuracy across a suite of benchmark functions. However, we show that differential grouping can only
identify decision variables that interact directly. Subsequently,
we propose an extension of differential grouping that is able tocorrectly identify decision variables that also interact indirectly.
Empirical studies show that our extended differential grouping
method achieves perfect decomposition on all of the benchmark

Global Line Search Algorithm Hybridized with Quadratic
Interpolation and Its Extension to Separable Functions
Petr Baudiš, Petr Pošı́k
We propose a novel hybrid algorithm ”Brent-STEP” for univariate global function minimization, based on the global line searchmethod STEP and accelerated by Brent’s method, a local optimizer that combines quadratic interpolation and golden section
steps. We analyze the performance of the hybrid algorithm onvarious one-dimensional functions and experimentally demonstrate a significant improvement relative to its constituent algorithms in most cases. We then generalize the algorithm to multivariate functions, proposing a scheme to interleave evaluations
across dimensions to achieve smoother and more efficient convergence. We experimentally demonstrate the highly competitive performance of the proposed multivariate algorithm on separable functions of the BBOB benchmark. The combination ofgood performance and smooth convergence on separable functions makes the algorithm an interesting candidate for inclusion
in algorithmic portfolios or hybrid algorithms that aim to provide good performance on a wide range of problems.

Digital Entertainment Technologies and Arts
DETA1
Solving Interleaved and Blended Sequential DecisionMaking Problems through Modular Neuroevolution
Jacob Schrum, Risto Miikkulainen
Many challenging sequential decision-making problems require
agents to master multiple tasks, such as defense and offense inmany games. Learning algorithms thus benefit from having sep-arate policies for these tasks, and from knowing when each one
is appropriate. How well the methods work depends on the nature of the tasks: Interleaved tasks are disjoint and have different
semantics, whereas blended tasks have regions where semantics
from different tasks overlap. While many methods work wellin interleaved tasks, blended tasks are difficult for methods withstrict, human-specified task divisions, such as Multitask Learning. In such problems, task divisions should be discovered auto-

Abstracts

matically. To demonstrate the power of this approach, the MMNEAT neuroevolution framework is applied in this paper to twovariants of the challenging video game of Ms. Pac-Man. In thesimplified interleaved version of the game, the results demonstrate when and why such machine-discovered task divisions areuseful. In the standard blended version of the game, a surprising, highly effective machine-discovered task division surpasses
human-specified divisions, achieving the best scores to date inthis game. Modular neuroevolution is thus a promising technique for discovering multimodal behavior for challenging realworld tasks.
DETA2
Controlling Crowd Simulations using Neuro-Evolution
Sunrise Wang, James Gain, Geoff Nistchke
Crowd simulations have become increasingly popular in films
over the last decade, appearing in large crowd shots of many
big name block-buster films. An important requirement forcrowd simulations in films is that they should be directable
both at a high and low level. As agent-based techniques allow for low-level directability and more believable crowds, they
are typically used in this field. However, due to the bottomup nature of these techniques, to achieve high level directability, agent-level parameters must be adjusted until the desired
crowd behavior emerges. As manually adjusting parameters isa time consuming and tedious process, this paper investigates amethod for automating this, using Neuro-Evolution. To this end,
the Conventional Neuro-Evolution (CNE), Covariance Matrix
Adaptation Evolutionary Strategy (CMA-ES), Neuro-Evolutionof Augmenting Topologies (NEAT), and Enforced Sub Populations (ESP) algorithms are compared across a variety of representative crowd simulation scenarios. Overall, it was found that
CMA-ES generally performs the best across the selected simulations.
Open Loop Search for General Video Game Playing
Diego Perez Liebana, Jens Dieskau, Martin Hunermund, Sanaz
Mostaghim, Simon Lucas
General Video Game Playing is a sub-field of Game Artificial Intelligence, where the goal is to find algorithms capable of playing many different real-time games, some of them unknown apriori. In this scenario, the presence of domain knowledge must
be severely limited, or the algorithm will overfit to the training games and perform poorly on the unknown games of thetest set. Research in this area has been of special interest in thelast years, with emerging contests like the General Video Game
AI (GVG-AI) Competition. This paper introduces three different open loop techniques for dealing with this problem. First,
a simple directed depth first search algorithm is employed as abaseline. Then, a tree search algorithm with a multi-armed bandit based tree policy is presented, followed by a Rolling Horizon
Evolutionary Algorithm (RHEA) approach. In order to test thesetechniques, the games from the GVG-AI Competition framework are used as a benchmark, evaluation on a training set of 29
games, and submitting to the 10 unknown games at the competition website. Results show how the general game-independent93

heuristic proposed works well across all algorithms and games,
and how the RHEA becomes the best evolutionary technique inthe rankings of the test set.
Darwin’s Avatars: a Novel Combination of Gameplay andProcedural Content Generation
Dan Lessin, Sebastian Risi
The co-evolution of morphology and control for virtual creatures
enables the creation of a novel form of gameplay and procedural content generation. Starting with a creature evolved to perform a simple task such as locomotion and removing its brain,
the remaining body can be employed in a compelling interactive control problem. Just as we enjoy the challenge and reward of mastering helicopter flight or learning to play a musical instrument, learning to control such a creature through manual activation of its actuators presents an engaging and rewarding puzzle. Importantly, the novelty of this challenge is inexhaustible, since the evolution of virtual creatures provides a way
to procedurally generate content for such a game. An endlessseries of creatures can be evolved for a task, then have theirbrains removed to become the game’s next human-control challenge. To demonstrate this new form of gameplay and content
generation, a proof-of-concept game–tentatively titled Darwin’s
Avatars–was implemented using evolved creature content, anduser tested. This implementation also provided a unique opportunity to compare human and evolved control of evolved virtual
creatures, both qualitatively and quantitatively, with interesting
implications for improvements and future work.
Interactively Evolving Compositional Sound Synthesis Networks
Björn Jónsson, Amy Hoover, Sebastian Risi
While the success of electronic music often relies on the uniqueness and quality of selected timbres, many musicians struggle
with complicated and expensive equipment and techniques tocreate their desired sounds. Instead, this paper presents a technique for producing novel timbres that are evolved by the musician through interactive evolutionary computation. Each timbre is produced by an oscillator, which is represented by a special type of artificial neural network (ANN) called a compositional pattern producing network (CPPN). While traditional
ANNs compute only sigmoid functions at their hidden nodes,
CPPNs can theoretically compute any function and can build on
those present in traditional synthesizers (e.g. square, sawtooth,triangle, and sine waves functions) to produce completely novel
timbres. Evolved with NeuroEvolution of Augmenting Topologies (NEAT), the aim of this paper is to explore the space ofpotential sounds that can be generated through such compositional sound synthesis networks (CSSNs). To study the effectof evolution on subjective appreciation, participants in a listenerstudy ranked evolved timbres by personal preference, resulting
in preferences skewed toward the first and last generations. In
the long run, the CSSN’s ability to generate a variety of different
and rich timbre opens up the intriguing possibility of evolving acomplete CSSN-encoded synthesizer.

94

Abstracts

Estimation of Distribution Algorithms
EDA1
Kernels of Mallows Models for Solving Permutation-based
Problems
Josu Ceberio, Alexander Mendiburu, Jose Lozano
Recently, distance-based exponential probability models, such
as Mallows and Generalized Mallows, have demonstrated theirvalidity in the context of estimation of distribution algorithms(EDAs) for solving permutation problems. However, despite
their successful performance, these models are unimodal, andtherefore, they are not flexible enough to accurately model populations with solutions that are very sparse with regard to the distance metric considered under the model. In this paper, we propose using kernels of Mallows models under the Kendall’s-tau
and Cayley distances within EDAs. In order to demonstrate thevalidity of this new algorithm, Mallows Kernel EDA, we compare its performance with the classical Mallows and Generalized
Mallows EDAs, on a benchmark of 90 instances of two different
types of permutation problems: the quadratic assignment problem and the permutation flowshop scheduling problem. Experimental results reveal that, in most cases, Mallows Kernel EDA
outperforms the Mallows and Generalized Mallows EDAs under the same distance. Moreover, the new algorithm under the
Cayley distance obtains the best results for the two problems interms of average fitness and computational time.
EDA2
Theoretical Perspective of Convergence Complexity of Evolutionary Algorithms Adopting Optimal Mixing
Yu-Fan Tung, Tian-Li Yu
The optimal mixing evolutionary algorithms (OMEAs) have recently drawn much attention for their robustness, small size of
required population, and efficiency in terms of number of function evaluations (NFE). In this paper, the performances and behaviors of convergence in OMEAs are studied by investigating
the mechanism of optimal mixing (OM), the variation operator in OMEAs, under two scenarios—one-layer and two-layer
masks. For the case of one-layer masks, the required population size is derived from the viewpoint of initial supply, while
the convergence time is derived by analyzing the progress of
sub-solution growth. NFE is then asymptotically bounded withrational probability by estimating the probability of performing
evaluations. For the case of two-layer masks, empirical results
indicate that the required population size is proportional to both
the degree of cross competition and the results from the onelayer-mask case. The derived models also indicate that population sizing is decided by initial supply when disjoint masks are
adopted, that the high selection pressure imposed by OM makes
the composition of sub-problems impact little on NFE, and thatthe population size requirement for two-layer masks increases
with the reverse-growth probability.

EDA3
Optimization by Pairwise Linkage Detection, Incremental
Linkage Set, and Restricted / Back Mixing: DSMGA-II
Shih-Huan Hsu, Tian-Li Yu
This paper proposes a new evolutionary algorithm, called
DSMGA-II, to efficiently solve optimization problems via exploiting problem substructures. The proposed algorithm adopts
pairwise linkage detection and stores the information in the formof dependency structure matrix (DSM). A new linkage model,
called the incremental linkage set, is then constructed by using
the DSM. Inspired by the idea of optimal mixing, the restricted
mixing and the back mixing are proposed. The former aims at
efficient exploration under certain constrains. The latter aims at
exploitation by refining the DSM so as to reduce unnecessary
evaluations. Experimental results show that DSMGA-II outperforms LT-GOMEA and hBOA in terms of number of function evaluations on the concatenated/folded/cyclic trap problems, NK-landscape problems with various degrees of overlapping, 2D Ising spin-glass problems, and MAX-SAT. The investigation of performance comparison with P3 is also included.
An Estimation of Distribution Algorithm based on the Natural Gradient and the Boltzmann Distribution
Ignacio Segovia-Dominguez, Arturo Hernandez-AguirreThis paper introduces an Estimation of Distribution Algorithm(EDA), in which the parameters of the search distribution are
updated by the natural gradient technique. The parameter updating is guided via the Kullback-Leibler divergence between
the multivariate Normal and the Boltzmann densities. This approach makes sense because it is well-known that the Boltzmann
function yields a reliable model to simulate particles near to optimum locations. Three main contributions are presented here inorder to build an effective EDA. The first one is a natural gradient formula which allows for an update of the parameters ofa density function. These equations are related to an exponential parametrization of the search distribution. The second contribution involves the approximation of the developed gradient
formula and its connection to the importance sampling method.
The third contribution is a parameter update rule which is designed to control the exploration and exploitation phases of thealgorithm. The proposed EDA is tested on a benchmark of 16
problems and compared versus the XNES and iAMaLGaM algorithms. The statistical results show that the performance of the
proposed method is competitive and it is the winner in several
problems.
Simplified Runtime Analysis of Estimation of Distribution
Algorithms
Duc-Cuong Dang, Per Kristian Lehre
Estimation of distribution algorithms (EDA) are stochastic
search methods that look for optimal solutions by learning andsampling from probabilistic models. Despite their popularity,

Abstracts

there are only few rigorous theoretical analyses of their performance. Even for the simplest EDAs, such as the Univariate
Marginal Distribution Algorithm (UMDA) which assumes independence between decision variables, there are only a handful of results about its runtime, and results for simple functions

95

such as Onemax are still missing. In this paper, we show thatthe recently developed level-based theorem for non-elitist populations is directly applicable to runtime analysis of EDAs. To
demonstrate this approach, we derive easily upper bounds on the
expected runtime of the UMDA.

Evolutionary Combinatorial Optimization and Metaheuristics
ECOM1
Fighting the Symmetries: The Structure of Cryptographic
Boolean Function Spaces
Stjepan Picek, Robert McKay, Roberto Santana, Tom Gedeon
We explore the problem space of maximum nonlinearity problems for balanced Boolean functions, examining the symmetry
structure and fitness landscapes in the most common (bit string)
representation. We present theoretical analyses of well understood aspects, together with detailed enumeration of the 4-bit
problem, sampling of the 6-bit problem based on known optima,
and sampling of the 8-bit problem based on its fittest known solutions. We show that these problems have many more symmetries than is generally noted, with implications for crossover andfor distributional methods. We explore the large-scale plateau
structure of the problem, with similar implications for local
search. We show that symmetries yield additional informationthat may yield more effective search methods.
Towards the User Equilibrium in Traffic Assignment Using
GRASP with Path Relinking
Gabriel Ramos, Ana Lucia Bazzan
Solving the traffic assignment problem (TAP) is an important
step towards an efficient usage of the traffic infrastructure. A
fundamental assignment model is the so-called User Equilibrium (UE), which may turn into a complex optimisation problem. In this paper, we present the use of the GRASP metaheuristic to approximate the UE of the TAP. A path relinking
mechanism is also employed to promote a higher coverage ofthe search space. Moreover, we propose a novel performance
evaluation function, which measures the number of vehicles thathave an incentive to deviate from the routes to which they wereassigned. Through experiments, we show that our approach outperforms classical algorithms, providing solutions that are, on
average, significantly closer to the UE. Furthermore, when compared to classical methods, the fairness achieved by our assignments is considerably better. These results indicate that our approach is efficient and robust, producing reasonably stable assignments.
A Visual Method for Analysis and Comparison of SearchLandscapes
Sebastian Volke, Dirk Zeckzer, Gerik Scheuermann, Martin
Middendorf
Combinatorial optimization problems and corresponding (meta-)heuristics have received much attention in the literature. Especially, the structural or topological analysis of search landscapes
is important for evaluating the applicability and the performanceof search operators for a given problem. However, this analysis is often tedious and usually the focus is on one specificproblem and only a few operators. We present a visual analysis method that can be applied to a wide variety of problems andsearch operators. The method is based on steepest descent walks
and shortest distances in the search landscape. The visualization shows the search landscape as seen by the search algorithm.
It supports the topological analysis as well as the comparisonof search landscapes. We showcase the method by applying it
to two different search operators on the TSP, the QAP, and the
SMTTP. Our results show how differences between search operators manifest in the search landscapes and how conclusions
about the suitability of the search operator for different optimizations can be drawn.
Predicting Heuristic Search Performance with PageRank
Centrality in Local Optima Networks
Sebastian Herrmann, Franz Rothlauf
Previous studies have used statistical analysis of fitness landscapes such as ruggedness and deceptiveness in order to predict the expected quality of heuristic search methods. Novelapproaches for predicting the performance of heuristic searchare based on the analysis of local optima networks (LONs). A
LON is a compressed stochastic model of a fitness landscape’s
basin transitions. Recent literature has suggested using various
LON network measurements as predictors for local search performance. In this study, we suggest PageRank centrality as a
new measure for predicting the performance of heuristic searchmethods using local search. PageRank centrality is a variant ofEigenvector centrality and reflects the probability that a node
in a network is visited by a random walk. Since the centralityof high-quality solutions in LONs determines the search difficulty of the underlying fitness landscape and since the big valley property suggests that local optima are not randomly distributed in the search space but rather clustered and close to one
another, PageRank centrality can serve as a good predictor for
local search performance. In our experiments for NK-models
and the traveling salesman problem, we found that the PageRank centrality is a very good predictor for the performance offirst-improvement local search as well as simulated annealing,
since it explains more than 90% of the variance of search performance. Furthermore, we found that PageRank centrality is a better predictor of search performance than traditional approaches

96

Abstracts

such as ruggedness, deceptiveness, and the length of the shortest
path to the optimum.

On the Impact of Local Search Operators and Variable
Neighbourhood Search for the Generalized Travelling Salesperson Problem

Guiding Evolutionary Search with Association Rules for
Solving Weighted CSPs

Mojgan Pourhassan, Frank Neumann

Madalina Raschip, Cornelius Croitoru, Kilian Stoffel
Weighted constraint satisfaction problems are difficult optimization problems that could model applications from various domains. Evolutionary algorithms are not the first option for solving such type of problems. In this work, the evolutionary algorithm uses the information extracted from the previous best solutions to guide the search in the next iterations. After the archiveof previous best solutions has been sufficiently (re)filled, a data
mining module is called to find association rules between variables and values. The generated rules are used to improve further
the search process. Different methods of applying the association rules are investigated. Computational experiments are doneon academic and real-world problem instances. The obtained results validate the approach and show that it is competitive withexisting approaches in literature.
ECOM2
A Genetic Algorithm for Scheduling Electric Vehicle Charging
Jorge Garcı́a-Álvarez, Miguel A. González, Camino R. Vela
This paper addresses a problem motivated by a real life environment, in which we have to schedule the charge of electricvehicles in a parking, subject to a set of constraints, with the objective of minimizing the total tardiness. We consider both thestatic version of the problem, where we know in advance the arrival time, charging time and due date of every vehicle, and also
the dynamic version of it. We design a genetic algorithm withsome components specifically tailored to deal with the problem.
In the experimental study we evaluate the proposed algorithm
in a benchmark set taken from the literature, and we also compare it against the state-of-the-art showing that our proposal issignificantly better.
A Dispatching rule based Genetic Algorithm for Order Acceptance and Scheduling
Su Nguyen, Mengjie Zhang, Tan Kay Chen
Order acceptance and scheduling is an interesting and chal- lenging scheduling problem in which two decisions need to be handled simultaneously. While the exact methods are not efficientand sometimes impractical, existing meta-heuristics proposed in
the literature still have troubles dealing with large problem instances. In this paper, a dispatching rule based genetic algorithm
is proposed to combine the advan- tages of existing dispatchingrules/heuristics, genetic algo- rithm and local search. The results
indicates that the pro- posed methods are effective and efficientwhen compared to a number of existing heuristics with a wide
range of problem instances.

The generalized travelling salesperson problem is an important NP-hard combinatorial optimization problem where local
search approaches have been very successful. We investigate thetwo hierarchical approaches of Hu and Raidl (2008) for solving
this problem from a theoretical perspective. We examine thecomplementary abilities of the two approaches caused by theirneighbourhood structures and the advantage of combining theminto variable neighbourhood search. We first point out complementary abilities of the two approaches by presenting instanceswhere they mutually outperform each other. Afterwards, we introduce an instance which is hard for both approaches, but wherea variable neighbourhood search combining them finds the optimal solution in polynomial time.
A Novel Diversity-based Evolutionary Algorithm for theTraveling Salesman Problem
Carlos Segura, Salvador Botello Rionda, Arturo Hernández
Aguirre, S. Ivvan Valdez Peña
The Traveling Salesman Problem (TSP) is one of the most wellknown NP-hard combinatorial optimization problems. In orderto deal with large TSP instances, several heuristics and metaheuristics have been devised. In this paper, a novel memetic
scheme that incorporates a new diversity-based replacement
strategy is proposed and applied to the largest instances of the
TSPLIB benchmark. The novelty of our method is that it combines the idea of transforming a single-objective problem intoa multi-objective one, by considering diversity as an explicit
objective, with the idea of adapting the balance induced between exploration and exploitation to the various optimization
stages. In addition, the intensification capabilities of the individual learning method incorporated in the memetic scheme arealso adapted by taking into account the stopping criterion. Computational results show the clear superiority of our scheme whencompared against state-of-the-art schemes. To our knowledge,
our proposal is the first evolutionary scheme that readily solves
an instance with more than 30,000 cities to optimality.
ECOM3
Global vs Local Search on Multi-objective NK-Landscapes:
Contrasting the Impact of Problem Features
Fabio Daolio, Arnaud Liefooghe, Sébastien Verel, Hernán
Aguirre, Kiyoshi Tanaka
Computationally hard multi-objective combinatorial optimization problems are common in practice, and numerous evolutionary multi-objective optimization (EMO) algorithms have been
proposed to tackle them. Our aim is to understand which(and how) problem features impact the search performance ofsuch approaches. In this paper, we consider two prototypicaldominance-based algorithms: a global EMO strategy using anergodic variation operator (GSEMO) and a neighborhood-basedAbstracts

local search heuristic (PLS). Their respective runtime is estimated on a benchmark of combinatorial problems with tunableruggedness, objective space dimension, and objective correlation (ρMNK-landscapes). In other words, benchmark parameters define classes of instances with increasing empirical problem hardness; we enumerate and characterize the search spaceof small instances. Our study departs from simple performancecomparison to systematically analyze the correlations between
runtime and problem features, contrasting their association withsearch performance within and across instance classes, for bothchosen algorithms. A mixed-model approach then allows us
to further generalize from the experimental design, supportinga sound assessment of the joint impact of instance features on
EMO search performance.
A Sequence-based Selection Hyper-heuristic Utilising a Hidden Markov Model
Ahmed Kheiri, Ed Keedwell
Selection hyper-heuristics are optimisation methods that operate at the level above traditional (meta-)heuristics. Their task isto evaluate low level heuristics and determine which of theseto apply at a given point in the optimisation process. Traditionally this has been accomplished through the evaluation ofindividual or paired heuristics. In this work, we propose a hidden Markov model based method to analyse the performance of,and construct, longer sequences of low level heuristics to solve
difficult problems. The proposed method is tested on the wellknown hyper-heuristic benchmark problems within the CHeSC
2011 competition and compared with a large number of algorithms in this domain. The empirical results show that the proposed hyper-heuristic is able to outperform the current best-inclass hyper-heuristic on these problems with minimal parametertuning and so points the way to a new field of sequence-based
selection hyper-heuristics.
Tunnelling Crossover Networks
Gabriela Ochoa, Francisco Chicano, Renato Tinos, Darrell
Whitley
Local optima networks are a recent model of fitness landscapes.
They compress the landscape by representing local optima as
nodes, and search transitions among them as edges. Previous
local optima networks considered transitions based on mutation; this study looks instead at transitions based on deterministic recombination. We define and analyse networks based on
the recently proposed partition crossover for k-bounded pseudoBoolean functions, using NKq landscapes as a case study. Partition crossover was initially proposed for the travelling salesman
problem, where it was found to “tunnel” between local optima,i.e., jump from local optimum to local optimum. Our network
analysis shows that this also happens for NK landscapes: local optima are densely connected via partition crossover. We
found marked differences between the adjacent and random interaction NK models. Surprisingly, with the random model, instances have a lower number of local optima on average, but
their networks are more sparse and decompose into several clus-

97

ters. There is also large variability in the size and pattern of connectivity of instances coming from the same landscape parameter values. These network features offer new insight informing
why some instances are harder to solve than others.
Hyperheuristics Based on Parametrized Metaheuristic
SchemesJosé-Matı́as Cutillas-Lozano, Domingo Giménez, Francisco
AlmeidaThe use of a unified parametrized scheme for metaheuristics facilitates the development of metaheuristics and their application.
The unified scheme can also be used to implement hyperheuristics on top of parametrized metaheuristics, selecting appropriate
values for the metaheuristic parameters, and consequently themetaheuristic itself. The applicability of hyperheuristics to efficiently solve computational search problems is tested with theapplication of local and global search methods (GRASP, Tabu
Search, Genetic algorithms and Scatter Search) and their combinations to three problems: a problem of optimization of power
consumption in operation of wells,the determination of the kinetic constants of a chemical reaction and the maximum diversity problem. The hyperheuristic approach provides satisfactory
values for the metaheuristic parameters and consequently satisfactory metaheuristics.
ECOM4
Minimizing Regular Objectives for Blocking Permutation
Flow Shop Scheduling: Heuristic Approaches
Nouha Nouri, Talel Ladhari
The objective of this work is to present and evaluate metaheuristics for the blocking permutation flow shop schedulingproblem subject to regular objectives. The blocking problem
is known to be NP-hard with more than two machines. We
assess the difficulty level of this problem by developing two
population-based meta-heuristics: Genetic Algorithm and Artificial Bee Colony algorithm. The final goal is to measure theperformance of these proposed techniques and potentially contribute in possible improvements in the blocking benchmark instances. Furthermore, computational tests carried out on randomly generated test problems show that the approaches consistently yields good solutions in a moderate amount of time. Finally, an updated list of best-known solutions for the Taillard’s
and Ronconi and Henriques’s benchmark is exposed: new bestknown solutions for the blocking flow shop scheduling problem
with makespan, total flow time, and total tardiness criteria arefound.
Approximate Approaches to the Traveling Thief Problem
Hayden Faulkner, Sergey Polyakovskiy, Tom Schultz, Markus
WagnerThis study addresses the recently introduced Traveling Thief
Problem (TTP) which combines the classical Traveling Salesman Problem (TSP) with the 0-1 Knapsack Problem (KP). The
problem consists of a set of cities, each containing a set of avail-98

Abstracts

able items with weights and profits. It involves searching fora permutation of the cities to visit and a decision on items topick. A selected item contributes its profit to the overall profit
at the price of higher transportation cost incurred by its weight.
The objective is to maximize the resulting profit. We propose anumber of problem-specific packing strategies run on top of TSP
solutions derived by the Chained Lin-Kernighan heuristic. The
investigations provided on the set of benchmark instances provetheir rapidity and efficiency when compared with an approximate mixed integer programming based approach and state-ofthe-art heuristic solutions from the literature.
On the Empirical Scaling Behaviour of State-of-the-art Local Search Algorithms for the Euclidean TSP
Jérémie Dubois-Lacoste, Holger Hoos, Thomas Stützle
We present a thorough empirical investigation of the scaling behaviour of state-of-the-art local search algorithms for the TSP;
in particular, we study the scaling of running time required forfinding optimal solutions to Euclidean TSP instances. We use arecently introduced bootstrapping approach to assess the statistical significance of the scaling models thus obtained and contrast
these models with those recently reported for the Concorde algorithm. In particular, we answer the question whether the scaling
behaviour of state-of-the-art local search algorithms for the TSP
differs by more than a constant from that required by Concorde
to find the first optimal solution to a given TSP instance.
Evaluation of a Multi-Objective EA on Benchmark Instances for Dynamic Routing of a Vehicle
Stephan Meisel, Christian Grimme, Jakob Bossek, MartinWölck, Günter Rudolph, Heike Trautmann
We evaluate the performance of a multi-objective evolutionary algorithm on a class of dynamic routing problems with asingle vehicle. In particular we focus on relating algorithmic
performance to the most prominent characteristics of problem
instances. The routing problem considers two types of customers: mandatory customers must be visited whereas optionalcustomers do not necessarily have to be visited. Moreover,mandatory customers are known prior to the start of the tour
whereas optional customers request for service at later points
in time with the vehicle already being on its way. The multiobjective optimization problem then results as maximizing thenumber of visited customers while simultaneously minimizing
total travel time. As an a-posteriori evaluation tool, the evolutionary algorithm aims at approximating the related Pareto set
for specifically designed benchmarking instances differing interms of number of customers, geographical layout, fraction of
mandatory customers, and request times of optional customers.
Conceptional and experimental comparisons to online heuristic
procedures are provided.
ECOM5
Generator Start-up Sequences Optimization for Network
Restoration Using Genetic Algorithm and Simulated Annealing
Paul Kaufmann, Cong Shen
In the domain of power grid systems, scheduling tasks arewidespread. Typically, linear programming (LP) techniques areused to solve these tasks. For cases with high complexity, linear system modeling is often cumbersome. There, other modeling approaches allow for a more compact representation being
typically also more accurate as non-linear dependencies can be
captured natively. In this work, we focus on the optimizationof a power plant start-up sequence, which is part of the network
restoration process of a power system after a blackout. Most
large power plants cannot start on their own without cranking energy from the outside grid. These are the non-black start (NBS)
units. As after a blackout we assume all power plants being shut
down, self-contained power plants (black start (BS) units), suchas the hydroelectric power plants, start first and boot the NBS
units one after each other. Once a NBS unit is restored, it supports the restoration process and because an average NBS unit ismuch larger than a BS unit, NBS unit’s impact on the restoration
process is typically dominant. The overall restoration process
can take, depending on the size of the blackout region and thedamaged components, some hours to weeks. And as the blackout time corresponds directly to economic and life losses, its
reduction, even by some minutes, is worthwhile. In this work
we compare two popular metaheuristics, the genetic (GA) andsimulated annealing (SA) algorithms on start-up sequence optimization and conclude that an efficient restoration plan can be
evolved reliably and, depending on the implementation, in a very
short period of time allowing for an integration into a real-timetransmission system operation tool.

Evolutionary Machine Learning
EML1
Retooling Fitness for Noisy Problems in a Supervised
Michigan-style Learning Classifier System
Ryan Urbanowicz, Jason Moore
An accuracy-based rule fitness is a hallmark of most modern
Michigan-style learning classifier systems (LCS), a powerful,flexible, and largely interpretable class of machine learners.

However, rule-fitness based solely on accuracy is not ideal for
identifying ‘optimal’ rules in supervised learning. This is particularly true for noisy problem domains where perfect rule accuracy essentially guarantees over-fitting. Rule fitness basedon accuracy alone is unreliable for reflecting the global ‘value’of a given rule since rule accuracy is based on a subset of the
training instances. While moderate over-fitting may not dramatically hinder LCS classification or prediction performance,Abstracts

the interpretability of the solution is likely to suffer. Additionally, over-fitting can impede algorithm learning efficiency andleads to a larger number of rules being required to capture relationships. The present study seeks to develop an intuitive
multi-objective fitness function that will encourage the discovery, preservation, and identification of ‘optimal’ rules throughaccuracy, correct coverage of training data, and the prior probability of the specified attribute states and class expressed by agiven rule. We demonstrate the advantages of our proposed fitness by implementing it into the ExSTraCS algorithm and performing evaluations over a large spectrum of complex, noisy,
simulated datasets.
High-Dimensional Function Approximation for KnowledgeFree Reinforcement Learning: a Case Study in SZ-Tetris
Wojciech Jaśkowski, Marcin Szubert, Paweł Liskowski,
Krzysztof Krawiec
SZ-Tetris, a restricted version of Tetris, is a difficult reinforcement learning task. Previous research showed that, similarly tothe original Tetris, value function-based methods such as temporal difference learning, do not work well for SZ-Tetris. The
best performance in this game was achieved by employing direct
policy search techniques, in particular the cross-entropy method
in combination with handcrafted features. Nonetheless, a simple heuristic hand-coded player scores even higher. Here weshow that it is possible to equal its performance with CMA-ES(Covariance Matrix Adaptation Evolution Strategy). We demonstrate that further improvement is possible by employing systematic n-tuple network, a knowledge-free function approximator,
and VD-CMA-ES, a linear variant of CMA-ES for high dimension optimization. Last but not least, we show that a large systematic n-tuple network (involving more than 4 million parameters) allows the classical temporal difference learning algorithm
to obtain similar average performance to VD-CMA-ES, but at
20 times lower computational expense, leading to the best policy for SZ-Tetris known to date. These results enrich the current
understanding of difficulty of SZ-Tetris, and shed new light on
the capabilities of particular search paradigms when applied torepresentations of various characteristics and dimensionality.
Simpler is Better: a Novel Genetic Algorithm to Induce
Compact Multi-label Chain Classifiers
Eduardo Gonçalves, Alexandre Plastino, Alex Freitas
Multi-label classification (MLC) is the task of assigning multiple class labels to an object based on the features that describe
the object. One of the most effective MLC methods is known asClassifier Chains (CC). This approach consists in training q binary classifiers linked in a chain, y1 -¿ y2 -¿ ... -¿ yq, with each
responsible for classifying a specific label in l1, l2, ..., lq. The
chaining mechanism allows each individual classifier to incorporate the predictions of the previous ones as additional information at classification time. Thus, possible correlations amonglabels can be automatically exploited. Nevertheless, CC suffersfrom two important drawbacks: (i) the label ordering is decided
at random, although it usually has a strong effect on predic-

99

tive accuracy; (ii) all labels are inserted into the chain, althoughsome of them might carry irrelevant information to discriminate
the others. In this paper we tackle both problems at once, by
proposing a novel genetic algorithm capable of searching for asingle optimized label ordering, while at the same time taking
into consideration the utilization of partial chains. Experimentson benchmark datasets demonstrate that our approach is able toproduce models that are both simpler and more accurate.
Subspace Clustering Using Evolvable Genome Structure
Sergio Peignier, Christophe Rigotti, Guillaume Beslon
In this paper we present an evolutionary algorithm to tackle
the subspace clustering problem. Subspace clustering is recognized as more difficult than standard clustering since it requires
to identify not only the clusters but also the various subspaces
where the clusters hold. We propose to tackle this problem witha bio-inspired algorithm that includes many bio-like features likevariable genome length and organization, functional and nonfunctional elements, and variation operators including chromosomal rearrangements. These features give the algorithm a large
degree of freedom to achieve subspace clustering with satisfying
results on a reference benchmark with respect to state of the art
methods. One of the main advantages of the approach is that itneeds only one subspace clustering ad-hoc parameter: the maximal number of clusters. This is a single and intuitive parameterthat sets the maximal level of details of the clustering, whileother algorithms require more complicated parameter space exploration. The other parameters of the algorithm are related tothe evolution strategy (population size, mutation rate, ...) and forthem we use a single setting that turns out to be effective on all
the datasets of the benchmark.
EML2Multiple Imputation for Missing Data Using Genetic Programming
Cao Truong Tran, Mengjie Zhang, Peter Andreae
Missing values are a common problem in many real world
databases. Inadequate handing of missing data can lead to serious problems in data analysis. A common way to cope withthis problem is to use imputation methods to fill missing values with plausible values. This paper proposes GPMI, a multiple imputation method that uses genetic programming as a regression method to estimate missing values. Experiments oneight datasets with six levels of missing values compare GPMI
with seven other popular and advanced imputation methods on
two measures: the prediction accuracy and the classification accuracy. The results show that, in most cases, GPMI not only
achieves better prediction accuracy, but also better classification
accuracy than the other imputation methods.
Genetically-regulated Neuromodulation Facilitates MultiTask Reinforcement Learning
Sylvain Cussat-Blanc, Kyle Harrington
In this paper, we use a gene regulatory network (GRN) to100

regulate a reinforcement learning controller, the State- ActionReward-State-Action (SARSA) algorithm. The GRN serves asa neuromodulator of SARSAs learning parame- ters: learning
rate, discount factor, and memory depth. We have optimized
GRNs with an evolutionary algorithm to regulate these parameters on specific problems but with no knowledge of problem
structure. We show that genetically- regulated neuromodulation(GRNM) performs comparably or better than SARSA with fixedparameters. We then ex- tend the GRNM SARSA algorithm tomulti-task problem generalization, and show that GRNs optimized on multi- ple problem domains can generalize to previously unknown problems with no further optimization.
Ant Colony and Surrogate Tree-Structured Models forOrderings-Based Bayesian Network Learning

Abstractstion problems with high number of objectives. The diversity ismeasured against a Reference Pareto Front, a set of points uniformly spread on the hyperplane with unit intercepts. We also
illustrate that the computation of such a metric is a natural extension of decomposition based evolutionary algorithms which attempt to align solutions with the reference directions constructedusing the Ideal point and uniformly distributed points on the hyperplane. In particular, the perpendicular distances between theuniformly distributed reference directions and their closest solutions in the nondominated front provides information about
the diversity, while the shortest distance of every solution fromthe hyperplane provides information about the convexity of the
POF. The proposed metrics are illustrated using a number of test
problems involving up to fifteen objectives.

Juan I. Alonso-Barba, Luis de la Ossa, Olivier Regnier-Coudert,
John McCall, José A. Gómez, José M. Puerta

Finding the Trade-off between Robustness and Worst-case
Quality

Structural learning of Bayesian networks is a very expensive taskeven when sacrifying the optimality of the result. Because ofthat, there are some proposals aimed at obtaining relative-quality
solutions in short times. One of them, namely Chain-ACO,
searches an ordering among all variables with Ant Colony Optimization and a chain-structured surrogate model, and then uses
this ordering to build a Bayesian network by means of the wellknown K2 algorithm. This work is based on Chain-ACO. We
evaluate the impact of using a tree-structured surrogate model
instead of a chain to evaluate orderings during the search. Moreover, we propose a variation of the way K2 builds the network,
which consists of allowing some changes in the positions of thevariables whenever they such changes not produce a cycle. This
modification of the process may improve the score of the final
network, without (almost) any additional cost.

Juergen Branke, Ke Lu

EMO1Characterizing Pareto Front Approximations in Manyobjective Optimization
Md Asafuddoula, Tapabrata Ray, Hemant SinghA Pareto Optimal Front (POF) provides the set of optimal tradeoff solutions formulti-objective optimization problems. The
characteristics of the POF, e.g. continuity, convexity, spreadand uniformity are important in the context of decision making
and performance assessment. Most of the existing metrics (hypervolume, inverted generational distance, coverage etc.) wereoriginally designed for two or three objective optimization problems with an aim of assessing the quality of non-dominated solutions delivered by various algorithms. The metrics provide
little information about the nature of the front and some of them(e.g. hypervolume) are computationally expensive for problems
involving large number of objectives. For problems with morethan three objectives, existing tools for visualization such as parallel plots, spider/radar plots and scatter plots also offer limited
useful information in terms of the nature of the front. In this paper, we introduce an alternative scalar measure of diversity thatis suitable for characterizing POF approximations of optimiza-

Many real-world problems are subject to uncertainty, and often
solutions should not only be good, but also robust against environmental disturbances or deviations from the decision variables. While most papers dealing with robustness aim at finding solutions with a high expected performance given a distribution of the uncertainty, we examine the trade-off between theallowed deviations from the decision variables (tolerance level),and the worst case performance given the allowed deviations.
A possible application are manufacturing tolerances, where anengineer can specify an allowed tolerance for manufacturing,
but a low tolerance requirement incurs substantially higher manufacturing cost, whereas a high tolerance requirement usuallymeans having to accept a lower worst-case quality of the solution.¡/par¿¡par¿More specifically, in this paper, we suggest two
multi- objective evolutionary algorithms to compute the available trade offs between allowed tolerance level and worst-casequality of the solutions. Both algorithms are 2-level nested algorithms. While the first algorithm is point-based in the sensethat the lower level computes a point of worst case for each upper level solution, the second algorithm is envelope-based, in thesense that the lower level computes a whole trade-off curve between worst-case oftness and tolerance level for each upper level
solution.
EMO2
Obtaining Optimal Pareto Front Approximations using
Scalarized Preference Information
Marlon Braun, Pradyumn Shukla, Hartmut Schmeck
Scalarization techniques are a popular method for articulating
preferences in solving multi-objective optimization problems.
These techniques, however, have so far proven to be ill-suited infinding a preference-driven approximation that still captures thePareto front in its entirety. Therefore, we propose a new conceptthat defines an optimal distribution of points on the front givena specific scalarization function. It is proven that such an approximation exists for every real-valued problem irrespective ofAbstracts

the shape of the corresponding front under some very mild conditions. We also show that our approach works well in obtaining an equidistant approximation of the Pareto front if no specific preference is articulated. Our analysis is complemented by
the presentation of a new algorithm that implements the afore-

101

mentioned concept. We provide in-depth simulation results todemonstrate the performance of our algorithm. The analysis also
reveals that our algorithm is able to outperform current state-ofthe-art algorithms on many popular benchmark problems.

Evolutionary Multiobjective Optimization
EMO1
A Study on Performance Evaluation Ability of a Modified
Inverted Generational Distance Indicator
Hisao Ishibuchi, Hiroyuki Masuda, Yusuke Nojima
The inverted generational distance (IGD) has been frequently
used as a performance indicator for many-objective problems
where the use of the hypervolume is difficult. However, since
IGD is not Pareto compliant, it is possible that misleading Pareto
incompliant results are obtained. Recently, a simple modification of IGD was proposed by taking into account the Pareto dominance relation between a solution and a reference point when
their distance is calculated. It was also shown that the modified
indicator called IGD+ is weakly Pareto compliant. However,actual effects of the modification on performance comparison
have not been examined. Moreover, IGD+ has not been compared with other distance-based weakly Pareto compliant indicators such as the additive epsilon indicator and the D1 indicator(i.e., IGD with the weighted achievement scalarizing function).
In this paper, we examine the effect of the modification by comparing IGD+ with IGD for multiobjective and many-objective
problems. In computational experiments, we generate a large
number of ordered pairs of non-dominated solution sets where
one is better than the other. Two solution sets in each pair arecompared by the above-mentioned performance indicators. We
examine whether each indicator can correctly say which solution
set is better between them.
Improved Sampling of Decision Space for Pareto Estimation
Yiming Yan, Ioannis Giagkiozis, Peter Fleming
Pareto Estimation (PE) is a novel method for increasing the density of Pareto optimal solutions across the entire Pareto Front orin a specific region of interest. PE identifies the inverse mapping of Pareto optimal solutions, namely, from objective space
to decision space. This identification can be performed using a
number of modeling techniques, how- ever, for the sake of simplicity in this work we use a radial basis neural network. In any
modeling method, the quality of the resulting model depends
heavily on the training samples used. The original version of
PE uses the result- ing set of Pareto optimal solutions from any
multi-objective optimization algorithm and then utilizes this set
to identify the aforementioned mapping. However, we argue that
this selection may not always be the best possible and propose
an alternative scheme to improve the resulting set of Pareto optimal solutions in order to produce higher quality samples forthe identification scheme in PE. The proposed approach is integrated with MAEA-gD, and the resulting solutions are used with
PE. The results show that the proposed method shows promise,in that there is measurable improvement in the quality of the estimated PE in terms of the coverage and density.
EMO2
An Experimental Investigation of Variation Operators in
Reference-Point Based Many-Objective Optimization
Yuan Yuan, Hua Xu, Bo Wang
Reference-point based multi-objective evolutionary algorithms(MOEAs) have shown promising performance in manyobjective optimization. However, most of existing researchwithin this area focused on improving the environmental selection procedure, and little work has been done on the effect ofvariation operators. In this paper, we conduct an experimental
investigation of variation operators in a typical reference-point
based MOEA, i.e., NSGA-III. First, we provide a new NSGA-III
variant, i.e., NSGA-III-DE, which introduces differential evolution (DE) operator into NSGA-III, and we further examine theeffect of two main control parameters in NSGA-III-DE. Second, we have an experimental analysis of the search behavior of
NSGA-III-DE and NSGA-III. We observe that NSGA-III-DE isgenerally better at exploration whereas NSGA-III normally has
advantages in exploitation. Third, based on this observation, we
present two other NSGA-III variants, where DE operator andgenetic operators are simply combined to reproduce solutions.
Experimental results on several benchmark problems show thatvery encouraging performance can be achieved by three suggested new NSGA-III variants. Our work also indicates thatthe performance of NSGA-III is significantly bottlenecked by
its variation operators, providing opportunities for the study ofthe other alternative ones.
Benchmarking Numerical Multiobjective Optimizers Revisited
Dimo Brockhoff, Thanh-Do Tran, Nikolaus Hansen
Algorithm benchmarking plays a vital role in designing new optimization algorithms and in recommending efficient and robustalgorithms for practical purposes. So far, two main approaches
have been used to compare algorithms in the evolutionary multiobjective optimization (EMO) field: (i) displaying empirical attainment functions and (ii) reporting statistics on quality indicator values. Most of the time, EMO benchmarking studies compare algorithms for fixed and often arbitrary budgets of func-

102tion evaluations although the algorithms are any-time optimizers. Instead, we propose to transfer and adapt standard benchmarking techniques from the single-objective optimization andclassical derivative-free optimization community to the field of
EMO. Reporting target-based runlengths allows to compare algorithms with varying numbers of function evaluations quantitatively. Displaying data profiles can aggregate performance
information over different test functions, problem difficulties,
and quality indicators. We apply this approach to compare threecommon algorithms on a new test function suite derived fromthe well-known single-objective BBOB functions. The focus
thereby lies less on gaining insights into the algorithms but moreon showcasing the concepts and on what can be gained over current benchmarking approaches.
Greedy Hypervolume Subset Selection in the ThreeObjective Case
Andreia Guerreiro, Carlos Fonseca, Luı́s Paquete
Given a non-dominated point set Xr ⊂ Rd of size n and a suitable reference point r ∈ Rd, the Hypervolume Subset Selection
Problem (HSSP) consists of finding a subset of size k ≤ n thatmaximizes the hypervolume indicator. It arises in connection
with multiobjective selection and archiving strategies, as well
as Pareto-front approximation post-processing for visualization
and/or interaction with a decision maker. Efficient algorithms
to solve the HSSP are available only for the 2-dimensional case,achieving a time complexity of O(n(k + logn)). In contrast, thedbest upper bound available for d > 2 is O(n 2 logn + nn−k ).
Since the hypervolume indicator is a monotone submodular
function, the HSSP can be approximated to a factor of (1 − 1/e)
using a greedy strategy. Such a greedy algorithm for the 3dimensional HSSP is proposed in this paper. The time complexity of the algorithm is shown to be O(n2 ), which considerably
improves upon recent complexity results for this approximation
problem.
EMO3
Improving Robustness of Stopping Multi-objective Evolutionary Algorithms by Simultaneously Monitoring Objectiveand Decision Space
Md Shahriar Mahbub, Tobias Wagner, Luigi Crema
Appropriate stopping criteria for multi-objective evolutionary
algorithms (MOEA) are an important research topic due to thecomputational cost of function evaluations, particularly on realworld problems. Most common stopping criteria are based ona fixed budget of function evaluations or the monitoring of theobjective space. In this work, we propose a stopping criterion
based on monitoring both the objective and decision space of aproblem. Average Hausdorff distance (AHD) and genetic diversity are used, respectively. Two-sided t-tests on the slope coefficients after regression analyses are used to detect the stagnationof the AHD and the genetic diversity. The approach is implemented for two widely used MOEAs: NSGA-II and SPEA2. It
is compared to a fixed budget, the online convergence detection

Abstracts

approach, and the individual monitoring of each space on fourbi-objective and two three-objective benchmark problems. Our
experimental results reveal that the combined approach achieved
significantly better results than the approaches considering only
one of the spaces. In particular, we find that the combined consideration runs longer and hence more robustly ensures a wellapproximated Pareto front. Nevertheless, on average 29% and
17% function evaluations are saved for NSGA-II and SPEA2,
respectively, compared to standard budget recommendations.
An Approach to Mitigating Unwanted Interactions between
Search Operators in Multi-Objective Optimization
Chad Byers, Betty Cheng
At run time, software systems often face a myriad of adverse
environmental conditions and system failures that cannot be anticipated during the system’s initial design phase. These uncertainties drive the need for dynamically adaptive systems thatare capable of providing self-* properties (e.g., self-monitoring,self-adaptive, self-healing, etc.). Prescriptive techniques to manually preload these systems with a limited set of configurations
often result in brittle, rigid designs that are unable to cope withenvironmental uncertainty. An alternative approach is to embed a search technique capable of exploring and generating optimal reconfigurations at run time. Increasingly, DAS applications are defined by multiple competing objectives (e.g., cost vs.
performance) in which a set of valid solutions with a range of
trade-offs are to be considered rather than a single optimal solution. While leveraging a multi-objective optimization technique,
NSGA-II, to manage these competing objectives, hidden interactions were observed between search operators that prevented faircompetition among solutions and restricted search from regions
where valid optimal configurations existed. In this follow-on
work, we demonstrate the role that niching can play in mitigating these unwanted interactions by explicitly creating favorable
regions within the objective space where optimal solutions canequally compete and co-exist.
Fast Implementation of the Steady-State NSGA-II Algorithm for Two Dimensions Based on Incremental NonDominated Sorting
Maxim Buzdalov, Ilya Yakupov, Andrey Stankevich
Genetic algorithms (GAs) are widely used in multi-objective optimization for solving complex problems. There are two distinct approaches for GA design: generational and steady-statealgorithms. Most of the current state-of-the-art GAs are generational, although there is an increasing interest to steady-statealgorithms as well. However, for algorithms based on nondominated sorting, most of steady-state implementations havehigher computation complexity than their generational counterparts, which limits their applicability. We present a fast implementation of a steady-state version of the NSGA-II algorithm fortwo dimensions. This implementation is based on a data structure which has O(N) complexity for single solution insertionand deletion in the worst case. The experimental results showthat our implementation works noticeably faster than steady-Abstracts

state NSGA-II implementations which use fast non-dominatedsorting.

103

A New Framework for Self-adapting Control Parameters in
Multi-objective Optimization
Xin Qiu, Weinan Xu, Jian-Xin Xu, Kay Chen Tan

A Performance Comparison Indicator for Pareto Front Approximations in Many-Objective Optimization
Miqing Li, Shengxiang Yang, Xiaohui Liu
Increasing interest in simultaneously optimizing many objectives (typically more than three objectives) of problems leads
to the emergence of various many-objective algorithms in theevolutionary multi-objective optimization field. However, incontrast to the development of algorithm design, how to assess
many-objective algorithms has received scant concern. Many
performance indicators are designed in principle for any numberof objectives, but in practice are invalid or infeasible to be usedin many-objective optimization. In this paper, we explain the difficulties that popular performance indicators face and propose aperformance comparison indicator (PCI) to assess Pareto front
approximations obtained by many-objective algorithms. PCI
evaluates the quality of approximation sets with the aid of a reference set constructed by themselves. The points in the reference
set are divided into many clusters, and the proposed indicator
estimates the minimum moves of solutions in the approximation
sets to weakly dominate these clusters. PCI has been verified
both by an analytic comparison with several well-known indicators and by an empirical test on four groups of Pareto front
approximations with different numbers of objectives and problem characteristics.
EMO4
Multi-objective Optimization with Dynamic Constraints andObjectives: New Challenges for Evolutionary Algorithms
Radhia Azzouz, Slim Bechikh, Lamjed Ben Said
Dynamic Multi-objective Optimization (DMO) is a challenging research topic since the objective functions, constraints, andproblem parameters may change over time. Several evolutionary algorithms have been proposed to deal with DMO problems.
Nevertheless, they were restricted to unconstrained or domain
constrained problems. In this work, we focus on the dynamictyof problem constraints along with time-varying objective functions. As this is a very recent research area, we have observed alack of benchmarks that simultaneously take into account thesecharacteristics. To fill this gap, we propose a set of test problems
that extend a suite of static constrained multi-objective problems. Moreover, we propose a new version of the Dynamic Non
dominated Sorting Genetic Algorithm II to deal with dynamic
constraints by replacing the used constraint-handling mechanism by a more elaborated and self-adaptive penalty function.
Empirical results show that our proposal is able to: (1) handle
dynamic environments and track the changing Pareto front and(2) handle infeasible solutions in an effective and efficient manner which allows avoiding premature convergence. Moreover,the statistical analysis of the obtained results emphasize the advantages of our proposal over the original algorithm on both aspects of convergence and diversity on most test problems.

Proper tuning of control parameters is critical to the performanceof a multi-objective evolutionary algorithm (MOEA). However,the developments of tuning methods for multi-objective optimization are insufficient compared to single-objective optimization. To circumvent this issue, this paper proposes a novel
framework that can self-adapt the parameter values from an
objective-based perspective. Optimal parametric setups for eachobjective will be efficiently estimated by combining singleobjective tuning methods with a grouping mechanism. Subsequently, the position information of individuals in objective
space is utilized to achieve a more efficient adaptation among
multiple objectives. The new framework is implemented into
two classical Differential-Evolution-based MOEAs to help toadapt the scaling factor F in an objective-wise manner. Threestate-of-the-art single-objective tuning methods are applied respectively to validate the robustness of the proposed mechanisms. Experimental results demonstrate that the new framework is effective and robust in solving multi-objective optimization problems.
Incorporating User Preferences in MOEA/D through the Coevolution of Weights
Martin Pilat, Roman Neruda
The resulting set of solutions obtained by MOEA/D depends on
the weights used in the decomposition. In this work, we use thisfeature to incorporate user preferences into the search. We use
co-evolutionary approach to change the weights adaptively during the run of the algorithm. After the user specifies their preferences by assigning binary preference values to the individuals,
the co-evolutionary step improves the distribution of weights bycreating new (offspring) weights and selecting those that better
match the user preferences. The algorithm is tested on a set ofbenchmark functions with a set of different user preferences.
Empirical Study of Multi-objective Ant Colony Optimization to Software Project Scheduling Problems
Jing Xiao, Mei-Ling Gao, Min-Mei Huang
The Software Project Scheduling Problem (SPSP) focuses on
the management of software engineers and tasks in a software
project so as to complete the tasks with a minimal cost and duration. Its becoming more and more important and challenging with the rapid development of software industry. In this paper, we employ a Multi-objective Evolutionary Algorithm using
Decomposition and Ant Colony (MOEA/D-ACO) to solve the
SPSP. To the best of our knowledge, it is the first application ofMulti-objective Ant Colony Optimization (MOACO) to SPSP.
Two heuristics capable of guiding the algorithm to search betterin the SPSP model are examined. Experiments are conducted ona set of 36 publicly available instances. The results are comparedwith the implementation of another multi-objective evolutionary algorithm called NSGA-II for SPSP. MOEA/D-ACO does

104

not outperform NSGA-II for most of complex instances in termsof Pareto Front. But MOEA/D-ACO can obtain solutions withmuch less time for all instances in our experiments and it outperforms NSGA-II with less duration for most of test instances.
The performance may be improved with tuning of the algorithm
such as incorporating more heuristic information or using other
MOACO algorithms, which deserve further investigation.
EMO5
A PSO Approach to Semivectorial Bilevel Programming:
Pessimistic, Optimistic and Deceiving Solutions
Maria João Alves, Carlos Antunes, Pedro Carrasqueira
In a bilevel programming problem, the upper level decision
maker (leader) decides first, but he must incorporate the reactionof the lower level decision maker (follower) in his decision. The
existence of multiple objectives at the lower level gives rise to aset of lower level efficient solutions for each leader’s decision,
which poses additional difficulties for the leader to anticipate
the follower’s reaction. The optimistic approach assumes thatthe follower accepts any efficient solution, while the pessimistic
approach considers that the leader prepares for the worst case. In
this work, we first discuss the assumptions and implications of
optimistic vs. pessimistic approaches in bilevel problems withmultiple objective functions at the lower level (semivectorial
bilevel problems) or at both levels. Three types of solutions areanalyzed: the optimistic, pessimistic and deceiving solutions,the latter being a new solution concept introduced herein, which
represents the worst outcome of a failed optimistic approach(i.e., when the leader believes that the follower will pursue his
own interests but the follower does not react accordingly). Then
we propose a particle swarm optimization algorithm to semivectorial bilevel problems, which aims to approximate these three
types of solutions in a single run. Some experimental results of
the algorithm are presented.
Multi-Objective BDD Optimization with Evolutionary Algorithms
Saeideh Shirinzadeh, Mathias Soeken, Rolf Drechsler
Binary Decision Diagrams (BDDs) are widely used in electronic
design automation and formal verification. BDDs are a canonical representation of Boolean functions with respect to a variable
ordering. Finding a variable ordering resulting in a small numberof nodes and paths is a primary goal in BDD optimization. There
are several approaches minimizing the number of nodes or paths
in BDDs, but yet no method has been proposed to minimize bothobjectives at the same time. In this paper, BDD optimization iscarried out as a bi-objective problem using two aforementioned
criteria. For this purpose, we have exploited NSGA-II which has
been proven to fit problems with a small number of objectives.
Furthermore, the algorithm is facilitated with an objective priority scheme that allows to incorporate preference to one of theobjectives. Experimental results show that our multi-objective
BDD optimization algorithm has achieved a good trade-off between the number of nodes and the number of paths. Compar-

Abstracts

ison of the results obtained by applying priority to the numberof nodes or paths with node and path minimization techniquesdemonstrates that the proposed algorithm can find the minimumof the preferred objective in most cases as well as lowering theother objective simultaneously.
MOEA/VAN: Multiobjective Evolutionary Algorithm Basedon Vector Angle Neighborhood
Roman Denysiuk, Lino Costa, Isabel Espı́rito Santo
Natural selection favors the survival and reproduction of organisms that are best adapted to their environment. Selection mechanism in evolutionary algorithms mimics this process, aiming
to create environmental conditions in which artificial organisms
could evolve solving the problem at hand. This paper proposes a
new selection scheme for evolutionary multiobjective optimization. The similarity measure that defines the concept of theneighborhood is a key feature of the proposed selection. Contrary to commonly used approaches, usually defined on the basis of distances between either individuals or weight vectors, it
is suggested to consider the similarity and neighborhood basedon the angle between individuals in the objective space. The
smaller the angle, the more similar individuals. This notion is
exploited during the mating and environmental selections. The
convergence is ensured by minimizing distances from individuals to a reference point, whereas the diversity is preserved by
maximizing angles between neighboring individuals. Experimental results reveal a highly competitive performance and useful characteristics of the proposed selection. Its strong diversity
preserving ability allows to produce a significantly better performance on some problems when compared with stat-of-the-art
algorithms.
Improved Metaheuristic Based on the R2 Indicator for
Many-Objective Optimization
Raquel Hernández Gómez, Carlos Coello CoelloIn recent years, performance indicators were introduced as a selection mechanism in multi-objective evolutionary algorithms(MOEAs). A very attractive option is the R2 indicator due to
its low computational cost and weak-Pareto compatibility. This
indicator requires a set of utility functions, which map each objective to a single value. However, not all the utility functions
available in the literature scale properly for more than four objectives and the diversity of the approximation sets is sensitive tothe choice of the reference points during normalization. In thispaper, we present an improved version of a MOEA based on theR2 indicator, which takes into account these two key aspects, using the achievement scalarizing function and statistical information about the population’s proximity to the true Pareto optimal
front. Moreover, we present a comparative study with respect tosome other emerging approaches, such as NSGA-III (based on
Pareto dominance), ∆p -DDE (based on the ∆p indicator) andsome other MOEAs based on the R2 indicator, using the DTLZ
and WFG test problems. Experimental results indicate that ourapproach outperforms the original algorithm as well as the other
MOEAs in the majority of the test instances, making it a suitable

Abstracts

alternative for solving many-objective optimization problems.
EMO6
Analysis of Objectives Relationships in Multiobjective Problems Using Trade-Off Region Maps
Rodrigo Pinheiro, Dario Landa-Silva, Jason Atkin
Understanding the relationships between objectives in manyobjective optimisation problems is desirable in order to develop
more effective algorithms. We propose a technique for the analysis and visualisation of complex relationships between many(three or more) objectives. This technique looks at conflicting,harmonious and independent objectives relationships from different perspectives. To do that, it uses correlation, trade-off regions maps and scatter-plots in a four step approach. We apply the proposed technique to a set of instances of the wellknown multiobjective multidimensional knapsack problem. The
experimental results show that with the proposed technique we
can identify local and complex relationships between objectives,trade-offs not derived from pairwise relationships, gaps in the fitness landscape, and regions of interest. Such information can beused to tailor the development of algorithms.
Injecting CMA-ES into MOEA/D
Saúl Zapotecas-Martı́nez, Bilel Derbel, Arnaud Liefooghe,
Dimo Brockhoff, Hernán Aguirre, Kiyoshi Tanaka
MOEA/D is an aggregation-based evolutionary algorithm which
has been proved extremely efficient and effective for solving
multi-objective optimization problems. It is based on the idea of
decomposing the original multi-objective problem into several
single-objective subproblems by means of well-defined scalarizing functions. Those single-objective subproblems are solvedin a cooperative manner by defining a neighborhood relation between them. This makes MOEA/D particularly interesting whenattempting to plug and to leverage single-objective optimizers ina multi-objective setting. In this context, we investigate the benefits that MOEA/D can achieve when coupled with CMA-ES,
which is believed to be a powerful single-objective optimizer.
We rely on the ability of CMA-ES to deal with injected solutions
in order to update different covariance matrices with respect toeach subproblem defined in MOEA/D. We show that by cooperatively evolving neighboring CMA-ES components, we are able
to obtain competitive results for different multi-objective benchmark functions.

105

On Maintaining Diversity in MOEA/D: Application to a
Biobjective Combinatorial FJSPJuan Jose Palacios, Bilel Derbel
MOEA/D is a generic decomposition-based multiobjective optimization framework which has been proved to be extremely
effective in solving a broad range of optimization problems especially for continuous domains. In this paper, we consider applying MOEA/D to solve a bi-objective scheduling combinatorial problem in which task durations and due-dates are uncertain.
Surprisingly, we find that the conventional MOEA/D implementation provides poor performance in our application setting. We
show that this is because the replacement strategy underlying
MOEA/D is suffering some shortcomes that lead to low population diversity, and thus to premature convergence. Consequently,
we investigate existing variants of MOEA/D and we propose anovel and simple alternative replacement component at the aimof maintaining population diversity. Through extensive experiments, we then provide a comprehensive analysis on the relative
performance and the behavior of the considered algorithms. Besides being able to outperform existing MOEA/D variants, aswell as the standard NSGA-II algorithm, our investigations provide new insights into the search ability of MOEA/D and highlight new research opportunities for improving its design components.
Parallel Multi-Objective Evolutionary Design of Approximate Circuits
Radek Hrbacek
Evolutionary design of digital circuits has been well establishedin recent years. Besides correct functionality, the demands
placed on current circuits include the area of the circuit andits power consumption. By relaxing the functionality requirement, one can obtain more efficient circuits in terms of the areaor power consumption at the cost of an error introduced to the
output of the circuit. As a result, a variety of trade-offs between error and efficiency can be found. In this paper, a multiobjective evolutionary algorithm for the design of approximate
digital circuits is proposed. The scalability of the evolutionary
design has been recently improved using parallel implementation of the fitness function and by employing spatially structured evolutionary algorithms. The proposed multi-objective approach uses Cartesian Genetic Programming for the circuit representation and a modified NSGA-II algorithm. Multiple isolated islands are evolving in parallel and the populations are
periodically merged and new populations are distributed acrossthe islands. The method is evaluated in the task of approximate
arithmetical circuits design.

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Abstracts

Generative and Developmental Systems
GDS1
Confronting the Challenge of Quality Diversity
Justin Pugh, L. Soros, Paul Szerlip, Kenneth Stanley
In contrast to the conventional role of evolution in evolutionary computation (EC) as an optimization algorithm, a new classof evolutionary algorithms has emerged in recent years that instead aim to accumulate as diverse a collection of discoveries as
possible, yet where each variant in the collection is as fit as it
can be. Often applied in both neuroevolution and morphological evolution, these new quality diversity (QD) algorithms are
particularly well-suited to evolution’s inherent strengths, thereby
offering a promising niche for EC within the broader field ofmachine learning. However, because QD algorithms are so new,until now no comprehensive study has yet attempted to systematically elucidate their relative strengths and weaknesses under
different conditions. Taking a first step in this direction, this paper introduces a new benchmark domain designed specificallyto compare and contrast QD algorithms. It then shows how thedegree of alignment between the measure of quality and the behavior characterization (which is an essential component of all
QD algorithms to date) impacts the ultimate performance of different such algorithms. The hope is that this initial study will
help to stimulate interest in QD and begin to unify the disparate
ideas in the area.
Enhancing Divergent Search through Extinction Events
Joel Lehman, Risto Miikkulainen
A challenge in evolutionary computation is to create representations as evolvable as those in natural evolution. This paper
hypothesizes that extinction events, i.e. mass extinctions, cansignificantly increase evolvability, but only when combined witha divergent search algorithm, i.e. a search driven towards diversity (instead of optimality). Extinctions amplify diversitygeneration by creating unpredictable evolutionary bottlenecks.
Persisting through multiple such bottlenecks is more likely forlineages that diversify across many niches, resulting in indirect
selection pressure for the capacity to evolve. This hypothesis
is tested through experiments in two evolutionary robotics domains. The results show that combining extinction events withdivergent search increases evolvability, while combining themwith convergent search offers no similar benefit. The conclusion is that extinction events may provide a simple and effective
mechanism to enhance performance of divergent search algorithms.

is still unclear, however, how some key parameters and algorithmic components influence the evolutionary dynamics and performance of novelty search. In this paper, we conduct a comprehensive empirical study focused on novelty search’s algorithmic
components. We study the ”k” parameter – the number of nearest neighbours used in the computation of novelty scores; theuse and function of an archive; how to combine novelty searchwith fitness-based evolution; and how to configure the mutation
rate of the underlying evolutionary algorithm. Our study is conducted in a simulated maze navigation task. Our results showthat the configuration of novelty search can have a significant
impact on performance and behaviour space exploration. We
conclude with a number of guidelines for the implementationand configuration of novelty search, which should help future
practitioners to apply novelty search more effectively.
GDS2
Evolving Soft Robots in Tight Spaces
Nick Cheney, Josh Bongard, Hod Lipson
Soft robots have become increasingly popular in recent years
and justifiably so. Their compliant structures and (theoretically) infinite degrees of freedom allow them to undertake tasks
which would be impossible for their rigid body counterparts,
such as conforming to uneven surfaces, efficiently distributing
stress, and passing through small apertures. Previous work in
the automated deign of soft robots has shown examples of thesesquishy creatures performing traditional robotic task like locomoting over flat ground. However, designing soft robots for
traditional robotic tasks fails to fully utilize their unique advantages. In this work, we present the first example of a soft
robot evolutionarily designed for reaching or squeezing througha small aperture a task naturally suited to its type of morphology.
We optimize these creatures with the CPPN-NEAT evolutionary
algorithm, introducing a novel implementation of the algorithm
which includes multi-objective optimization while retaining its
speciation feature for diversity maintenance. We show that more
compliant and deformable soft robots perform more effectively
at this task than their less flexible counterparts. This work serves
mainly as a proof of concept, but we hope that it helps to open
the door for the better matching of tasks with appropriate morphologies in robotic design in the future.
Innovation Engines: Automated Creativity and Improved
Stochastic Optimization via Deep Learning
Anh Nguyen, Jason Yosinski, Jeff Clune

Devising Effective Novelty Search Algorithms: A Comprehensive Empirical Study
Jorge Gomes, Pedro Mariano, Anders Christensen
Novelty search is a state-of-the-art evolutionary approach that
promotes behavioural novelty instead of pursuing a static objective. Along with a large number of successful applications,many different variants of novelty search have been proposed. It

The Achilles Heel of stochastic optimization algorithms is getting trapped on local optima. Novelty Search avoids this problem by encouraging a search in all interesting directions. That
occurs by replacing a performance objective with a reward fornovel behaviors, as defined by a human-crafted, and often simple, behavioral distance function. While Novelty Search isa major conceptual breakthrough and outperforms traditional

Abstracts

stochastic optimization on certain problems, it is not clear how toapply it to challenging, high-dimensional problems where specifying a useful behavioral distance function is difficult. For example, in the space of images, how do you encourage novelty to
produce hawks and heroes instead of endless pixel static? Here
we propose a new algorithm, the Innovation Engine, that builds
on Novelty Search by replacing the human-crafted behavioral
distance with a Deep Neural Network (DNN) that can recognize
interesting differences between phenotypes. The key insight isthat DNNs can recognize similarities and differences between
phenotypes at an abstract level, wherein novelty means interesting novelty. For example, a novelty pressure in image space107

does not explore in the low-level pixel space, but instead creates a pressure to create new types of images (e.g. churches,mosques, obelisks, etc.). Here we describe the long-term vision
for the Innovation Engine algorithm, which involves many technical challenges that remain to be solved. We then implementa simplified version of the algorithm that enables us to explore
some of the algorithm’s key motivations. Our initial results, inthe domain of images, suggest that Innovation Engines could ultimately automate the production of endless streams of interesting solutions in any domain: e.g. producing intelligent software,robot controllers, optimized physical components, and art.

Genetic Algorithms
GA1
Parasite Diversity in Symbiogenetic Multiset Genetic Algorithm - Optimization of Large Binary Problems
António Manso, Luı́s Correia
Symbiogenetic MuGA (SMuGA) is a co-evolutionary model
exploiting the concept of symbiosis over the Multiset Genetic
Algorithm (MuGA). It evolves two species: hosts that represent a solution to the problem, and parasites that represent partsolutions. SMuGA has been proved valuable in the optimizationof a variety of deceptive functions. However its performancedecreased in large scale difficult problems. This paper presents
a new version of SMuGA with improvements centered on theevolution process of the parasites. The most significant advanceis provided by using a diversity measure to modulate the evolution of parasites. The algorithm is tested with very good resultsin deceptive functions with up to 1024 bits. The paper is concluded with an analysis of the advantages and limitations of theapproach, and with perspectives for future developments.
Gray-Box Optimization using the Parameter-less Population
Pyramid
Brian Goldman, William Punch
Unlike black-box optimization problems, gray-box optimization
problems have known, limited, non-linear relationships between
variables. Though more restrictive, gray-box problems include
many real-world applications in network security, computational
biology, VLSI design, and statistical physics. Leveraging theserestrictions, the Hamming-Ball Hill Climber (HBHC) can efficiently find high quality local optima. We show how 1) a simple
memetic algorithm in conjunction with HBHC can find global
optima for some gray-box problems and 2) a gray-box versionof the Parameter-less Population Pyramid (P3), utilizing both the
HBHC and the known information about variable relationships,
outperforms all of the examined algorithms. While HBHC’s
inclusion into P3 adds a parameter, we show experimentally it
can be fixed to 1 without adversely effecting search. We provide experimental evidence on NKq-Landscapes and Ising Spin
Glasses that Gray-Box P3 is effective at finding the global op-

tima even for problems with thousands of variables. This capability is complemented by its efficiency, with running time andmemory usage decreased by up to a linear factor from BlackBox P3. On NKq this results in a 375x speedup for problems
with at least 1,000 variables.
Evolutionary Bilevel Optimization for Complex Control
Tasks
Jason Liang, Risto Miikkulainen
Most optimization algorithms must undergo time consuming parameter adaptation in order to optimally solve complex, realworld control tasks. Parameter adaptation is inherently a bilevel
optimization problem where the lower level objective functionis the performance of the control parameters discovered by an
optimization algorithm and the upper level objective function is
the performance of the algorithm given its parametrization. In
this paper, a novel method called MetaEvolutionary Algorithm(MEA) is presented and shown to be capable of efficiently discovering optimal parameters for neuroevolution to solve control
problems. In two challenging examples, double pole balancing
and helicopter hovering, MEA discovers optimized parametersthat result in better performance than hand tuning and other automatic methods. Bilevel optimization in general and MEA in
particular, is thus a promising approach for solving difficult control tasks.
Mk Landscapes, NK Landscape, MAX-kSAT
Darrell WhitleyThis paper investigates Gray Box Optimization for pseudoBoolean optimization problems composed of M subfunctions,where each subfunction accepts at most k variables. We will refer to these as Mk Landscapes. In Gray Box optimization, theoptimizer is given access to the set of M subfunctions. If the setof subfunctions is k-bounded and separable, the Gray Box optimizer is guaranteed to return the global optimum with 1 evaluation. A problem is said to be order k deceptive if the averagevalues of hyperplanes over combinations of k variables cannot
be used to infer a globally optimal solution. Hyperplane aver-108

ages are always efficiently computable for Mk Landscapes. If
a problem is not deceptive, the Gray Box optimizer also returns
the global optimum after 1 evaluation. Finally, these concepts
are used to understand the nonlinearity of problems in the complexity class P, such as Adjacent NK Landscapes. These ideas
are also used to understand the problem structure of NP Hard
problems such as MAX-kSAT and general Mk Landscapes. In
general, NP Hard problems are profoundly deceptive.
GA2
Maintaining 2-Approximations for the Dynamic Vertex
Cover Problem Using Evolutionary Algorithms
Mojgan Pourhassan, Wanru Gao, Frank Neumann
Evolutionary algorithms have been frequently used to deal withdynamic optimization problems, but their success is hard to understand from a theoretical perspective. With this paper, we
contribute to the theoretical understanding of evolutionary algorithms for dynamic combinatorial optimization problems. We
examine a dynamic version of the classical vertex cover problem
and analyse evolutionary algorithms with respect to their ability
to maintain a 2-approximation. Analysing the different evolutionary algorithms studied by Jansen et al. (2013), we point out
where two previously studied approaches are not able to maintain a 2-approximation even if they start with a solution of that
quality. Furthermore, we point out that the third approach isvery effective in maintaining 2-approximations for the dynamic
vertex cover problem.
A Tensor Analysis Improved Genetic Algorithm for Online
Bin Packing
Shahriar Asta, Ender Ozcan
Mutation in a Genetic Algorithm is the key variation operator
adjusting the genetic diversity in a population throughout theevolutionary process. Often, a fixed mutation probability is used
to perturb the value of a gene. In this study, we describe a novel
data science approach to adaptively generate the mutation probability for each locus. The trail of high quality candidate solutions obtained during the search process is represented as a
3rd order tensor. Factorizing that tensor captures the common
pattern between those solutions, identifying the degree of mutation which is likely to yield improvement at each locus. An
online bin packing problem is used as an initial case study to investigate the proposed approach for generating locus dependent
mutation probabilities. The empirical results show that the tensor approach improves the performance of a standard Genetic
Algorithm on almost all classes of instances, significantly.
Adaptive Control of Parameter-less Population Pyramid on
the Local Distribution of Inferior Individuals
Kazuyuki Inoue, Taku Hasegawa, Yuta Araki, Naoki Mori,
Keinosuke Matsumoto
Many evolutionary techniques such as genetic algorithms (GAs)
employ parameters that facilitate user control of search dynamics. However, these parameters require time-consuming tun-

Abstracts

ing processes to avoid problems such as premature convergence.
Unlike many GAs, the Parameter-less Population Pyramid (P3)
is an optimization model that avoids premature convergence dueto the pyramid-like structure of populations, and thus P3 canbe applied to a wide range of problems without parameter tuning. P3 approaches to search would be useful for constructing
a novel theory for optimal search using GAs. In this study, we
propose a novel technique “analysis based on the Distribution ofInferior Individuals in the local neighborhood” (DII analysis).
DII analysis can be applied to local search techniques, including P3. The computational complexity of applied problems canbe estimated based on a number of local optima according to
the results obtained using DII. We also propose combining P3
with DII analysis (P3-DII), which controls the maximum number of fitness evaluations performed by genetic operators. The
computational experiments were carried out taking several combinational problems as examples. According to our experimental results, we demonstrated that P3-DII found several optimal
solutions that P3 failed to find.
A Genetic Algorithm for Searching the Shortest Lattice Vector of SVP Challenge
Dan Ding, Guizhen Zhu, Xiaoyun Wang
In this paper, we propose a genetic algorithm for solving theshortest vector problem (SVP) based on sparse representationof short lattice vectors, which, we prove, can guarantee finding
the shortest lattice vector under a Markov analysis. With someheuristic improvements (local search and heuristic pruning), the
SVP genetic algorithm, by experimental results, outperforms
other SVP algorithms, like the famous Kannan-Helfrich algorithm under SVP challenge benchmarks. In summary, we, forthe first time, adopt the genetic algorithm in solving the shortest
vector problem, based on which lattice-based cryptosystem is as
a promising candidate for post-quantum cryptography.
An Empirical Analysis on Dimensionality in Cellular Genetic Algorithms
Alicia Morales-Reyes, Hugo Jair Escalante, Martin Letras, Rene
Cumplido
Cellular or fine grained Genetic Algorithms (GAs) are a massively parallel algorithmic approach to GAs. Decentralizing
their population allows alternative ways to explore and to exploit
the solutions landscape. Individuals interact locally throughnearby neighbors while the entire population is globally exploring the search space throughout a predefined population’s topology. Having a decentralized population requires the definitionof other algorithmic configuration parameters; such as shapeand number of individuals within the local neighborhood, population’s topology shape and dimension, local instead of global
selection criteria, among others. In this article, attention ispaid to the population’s topology dimension in cGAs. Several
benchmark problems are assessed for 1, 2, and 3 dimensions
while combining a local selection criterion that significantly affect overall selective pressure. On the other hand, currently
available high performance processing platforms such as Field

Abstracts

Programmable Gate Arrays (FPGAs) and Graphics Processing
Units (GPUs) offer massively parallel fabrics. Therefore, having
a strong empirical base to understand structural properties in cellular GAs would allow to combine physical properties of theseplatforms when designing hardware architectures to tackle difficult optimization problems where timing constraints are mandatory.
GA3
A Genetic Algorithm to Solve a Real 2-D Cutting Stock Problem with Setup Cost in the Paper Industry
Stephane Bonnevay, Philippe Aubertin, Gerald Gavin
This paper deals with the Two-Dimensional Cutting Stock Problem with Setup Cost (2CSP-S). This problem is composed ofthree optimization sub-problems: a 2-D Bin Packing (2BP)
problem (to place images on patterns), a Linear Programming(LP) problem (to find for each pattern the number of stock sheets
to be printed) and a combinatorial problem (to find the number of
each image on each pattern). In this article, we solve the 2CSPS focusing on this third sub-problem. A genetic algorithm wasdeveloped to automatically find the proper number of each image on patterns. It is important to notice that our approach is
not a new packing technique. This work was conducted for apaper industry company and experiments were realized on real
and artificial datasets.
A New Perspective on Channel Allocation in WLAN: Considering the Total Marginal Utility of the Connections for
the Users
Thiago Luiz, Alan Freitas, Frederico Guimarães
The channel allocation problem consists in defining the frequency used by Access Points (APs) in Wireless Local Area Networks (WLAN). An overlap of channels in a WLAN is the major
factor of performance reduction for the users in a network. For
this reason, we propose a new model for channel allocation thataims to maximize the total quality of the connection of the user
by considering their marginal utility. The results show that anallocation model that does not take into account the total utilityof each connection tends to prioritize the quality of connectionof a few users and lead to a large unbalance in the distributionof connection speed between users. Thus, the new model canhandle the importance of degradation caused by the levels of interference in the user connection separately.
Reconstructing Cross-Cut Shredded Text Documents: A Genetic Algorithm with Splicing-Driven Reproduction
Yong-Feng Ge, Yue-Jiao Gong, Wei-Jie Yu, Xiao-Min Hu, Jun
Zhang
In this work we focus on reconstruction of cross-cut shredded
text documents (RCCSTD), which is of high interest in the fields
of forensics and archeology. A novel genetic algorithm, withsplicing-driven crossover, four mutation operators, and a roworiented elitism strategy, is proposed to improve the capabilityof solving RCCSTD in complex space. We also design a novel

109

and comprehensive objective function based on both edge andempty vector-based splicing error to guarantee that the correct
reconstruction always has the lowest cost value. Experiments are
conducted on six RCCSTD scenarios, with experimental results
showing that the proposed algorithm significantly outperforms
the previous best-known algorithms for this problem.
A Clustering-Based Model-Building EA for Optimization
Problems with Binary and Real-Valued Variables
Krzysztof Sadowski, Peter Bosman, Dirk Thierens
We propose a novel clustering-based model-building evolutionary algorithm to tackle optimization problems that have both binary and real-valued variables. The search space is clustered
every generation using a distance metric that considers binary
and real-valued variables jointly in order to capture and exploit
dependencies between variables of different types. After clustering, linkage learning takes place within each cluster to captureand exploit dependencies between variables of the same type.
We compare this with a model-building approach that only considers dependencies between variables of the same type. Additionally, since many real-world problems have constraints, we
examine the use of different well-known approaches to handling constraints: constraint domination, dynamic penalty andglobal competitive ranking. We experimentally analyze the performance of the proposed algorithms on various unconstrained
problems as well as a selection of well-known MINLP benchmark problems that all have constraints, and compare our results with the Mixed-Integer Evolution Strategy (MIES). We findthat our approach to clustering that is aimed at the processing ofdependencies between binary and real-valued variables can significantly improve performance in terms of required population
size and function evaluations when solving problems that exhibit
properties such as multiple optima, strong mixed dependencies
and constraints.
GA4
Elitist Black-Box Models: Analyzing the Impact of Elitist
Selection on the Performance of Evolutionary Algorithms
Carola Doerr, Johannes Lengler
Black-box complexity theory provides lower bounds for the runtime %classes of black-box optimizers like evolutionary algorithms and serves as an inspiration for the design of new genetic algorithms. Several black-box models covering different
classes of algorithms exist, each highlighting a different aspectof the algorithms under considerations. In this work we add tothe existing black-box notions a new elitist black-box model, in
which algorithms are required to base all decisions solely on(a fixed number of) the best search points sampled so far. Ourmodel combines features of the ranking-based and the memoryrestricted black-box models with elitist selection. We provide
several examples for which the elitist black-box complexity is
exponentially larger than that the respective complexities in all
previous black-box models, thus showing that the elitist blackbox complexity can be much closer to the runtime of typical110

Abstracts

evolutionary algorithms. We also introduce the concept of pMonte Carlo black-box complexity, which measures the time ittakes to optimize a problem with failure probability at most p.
Even for small p, the p-Monte Carlo black-box complexity of afunction class F can be smaller by an exponential factor than its
typically regarded Las Vegas complexity (which measures the
expected time it takes to optimize F ).

mutation-based EA for onemax, a question left open in [Sudholt,
IEEE TEC 2013]. At the heart of our analysis is a very precise
bound for the maximum of k independent Binomially distributed
variables with success probability 1/2.

Money for Nothing: Speeding Up Evolutionary Algorithms
Through Better Initialization

Benjamin Doerr, Carola Doerr, Timo Kützing

Axel de Perthuis de Laillevault, Benjamin Doerr, Carola Doerr
That the initialization can have a significant impact on the performance of evolutionary algorithms (EAs) is a well known fact
in the empirical evolutionary computation literature. Surprisingly, it has nevertheless received only little attention from thetheoretical community. We bridge this gap by providing a thorough runtime analysis for a simple iterated random sampling
initialization. In the latter, instead of starting an EA with a random sample, it is started in the best of k search points that are
taken from the search space uniformly at random. Implementing this strategy comes at almost no cost, neither in the actual
coding work nor in terms of wall-clock time. Taking the best of
two random samples already decreases the Θ(n log n) expected
runtime of the (1+1) EA and Randomized Local Search on one√max by an additive term of order n. The optimal gain that
one can achieve√ with iterated random sampling is an additive
term of order n log n. This also determines the best possible

Solving Problems with Unknown Solution Length at (Almost) No Extra Cost

Most research in the theory of evolutionary computation assumes that the problem at hand has a fixed problem size. This assumption does not always apply to real-world optimization challenges, where the length of an optimal solution may be unknowna priori. Following up on previous work of Cathabard, Lehre,and Yao [FOGA 2011] we analyze variants of the (1+1) evolutionary algorithm for problems with unknown solution length.
For their setting, in which the solution length is sampled froma geometric distribution, we provide mutation rates that yieldan expected optimization time that is of the same order as thatof the (1+1) EA knowing the solution length. We then showthat almost the same run times can be achieved even if no a priori information on the solution length is available. Finally, we
provide mutation rates suitable for settings in which neither thesolution length nor the positions of the relevant bits are known.
Again we obtain almost optimal run times for the O NE M AX andL EADING O NES test functions, thus solving an open problem
from Cathabard et al.

Genetic Programming
GP1
Correlation Immunity of Boolean Functions: An Evolutionary Algorithms Perspective
Stjepan Picek, Claude Carlet, Domagoj Jakobovic, Julian Miller,
Lejla Batina
Boolean functions are essential in many stream ciphers. Whenused in combiner generators, they need to have sufficiently highvalues of correlation immunity, alongside other properties. In
addition, correlation immune functions with small Hamming
weight reduce the cost of masking countermeasures against sidechannel attacks. Various papers have examined the applicabilityof evolutionary algorithms for evolving cryptographic Booleanfunctions. However, even when authors considered correlation
immunity, it was not given the highest priority. Here, we examine the effectiveness of three different EAs, namely, Genetic
Algorithms, Genetic Programming (GP) and Cartesian GP for
evolving correlation immune Boolean functions. Besides theproperties of balancedness and correlation immunity, we consider several other relevant cryptographic properties while maintaining the optimal trade-offs among them. We show that evolving correlation immune Boolean functions is an even harder objective than maximizing nonlinearity.

Building Predictive Models via Feature Synthesis
Ignacio Arnaldo, Una-May O’Reilly, Kalyan Veeramachaneni
We introduce Evolutionary Feature Synthesis (EFS), a regression method that generates readable, nonlinear models of small
to medium size datasets in seconds. EFS is, to the best of ourknowledge, the fastest regression tool based on evolutionary
computation reported to date. The feature search involved in
the proposed method is composed of two main steps: featurecomposition and feature subset selection. EFS adopts a bottomup feature composition strategy that eliminates the need for a
symbolic representation of the features and exploits the variableselection process involved in pathwise regularized linear regression to perform the feature subset selection step. The result isa regression method that is competitive against neural networks,
and outperforms both linear methods and Multiple Regression
Genetic Programming, up to now the best regression tool basedon evolutionary computation.
Impact of Crossover Bias in Genetic Programming
Nicholas McPhee, M. Dramdahl, David Donatucci
In tree-based genetic programming (GP) with sub-treecrossover, the parent contributing the root portion of the tree (theroot parent) often contributes more to the semantics of the re-Abstracts

sulting child than the non-root parent. Previous research demonstrated that when the root parent had greater fitness than the nonroot parent, the fitness of the child tended to be better than if thereverse were true. Here we explore the significance of that asymmetry by introducing the notion of crossover bias, where we bias
the system in favor of having the more fit parent as the root parent. In this paper we apply crossover bias to several problems.
In most cases we found that crossover bias either improved performance or had no impact. We also found that the effectivenessof crossover bias is dependent on the problem, and significantly
dependent on other parameter choices. While this work focuses
specifically on sub-tree crossover in tree-based GP, artificial andbiological evolutionary systems often have substantial asymmetries, many of which remain understudied. This work suggeststhat there is value in further exploration of the impacts of theseasymmetries.
Strength Through Diversity: Disaggregation and MultiObjectivisation Approaches for Genetic Programming
Jonathan Fieldsend, Alberto Moraglio
An underlying problem in genetic programming (GP) is how
to ensure sufficient useful diversity in the population during
search. Having a wide range of diverse (sub)component structures available for recombination and/or mutation is importantin preventing premature converge. We propose two new fitness
disaggregation approaches that make explicit use of the information in the test cases (i.e., program semantics) to preserve diversity in the population. The first method preserves the best
programs which pass each individual test case, the second preserves those which are non-dominated across test cases (multiobjectivisation). We use these in standard GP, and compare themto using standard fitness sharing, and using standard (aggregate)
fitness in tournament selection. We also examine the effect ofincluding a simple anti-bloat criterion in the selection mechanism. We find that the non-domination approach, employing
anti-bloat, significantly speeds up convergence to the optimum
on a range of standard Boolean test problems. Furthermore, itsbest performance occurs with a considerably smaller population
size than typically employed in GP.

111

reachable states of the given program and identifying whether
it satisfies its specification. We present scenario-based multiobjective approach that each program is evaluated under different scenarios which represent various environments. The computation of the programs are considered in two different semantics respectively: interleaving and maximum-parallelism. In
the end, we illustrate our approach with a Byzantine agreement
problem, a token ring problem and a consensus protocol using
failure detector S. For the first time, this work automatically synthesizes the consensus protocol with S. The results show the proposed method enhances the effectiveness of GP in all studied
cases when using maximum-parallelism semantic.
Examining the “Best of Both Worlds” of Grammatical EvolutionPeter Whigham, Grant Dick, James Maclaurin, Caitlin Owen
Grammatical Evolution (GE) has a long history in evolutionary
computation. Central to the behaviour of GE is the use of a linear representation and grammar to map individuals from search
spaces into problem spaces. This genotype to phenotype mapping is often argued as a distinguishing property of GE relative
to other techniques, such as context-free grammar genetic programming (CFG-GP). Since its initial description, GE research
has attempted to incorporate information from the grammar intocrossover, mutation, and individual initialisation, blurring thedistinction between genotype and phenotype and creating GE
variants closer to CFG-GP. This is argued to provide GE with the”best of both worlds”, allowing degrees of grammatical bias to
be introduced into operators to best suit the given problem. This
paper examines the behaviour of three grammar-based searchmethods on several problems from previous GE research. It isshown that, unlike CFG-GP, the performance of ”pure” GE on
the examined problems closely resembles that of random search.
The results suggest that further work is required to determine thecases where the ”best of both worlds” of GE are required over a
straight CFG-GP approach.
Performance Optimization of Multi-Core Grammatical Evolution Generated Parallel Recursive Programs
Gopinath Chennupati, R. Muhammad Azad, Conor Ryan

GP2
Using Model Checking Techniques For Evaluating the Effectiveness of Evolutionary Computing in Synthesis of Distributed Fault-Tolerant Programs
Ling Zhu, Sandeep Kulkarni
In most applications using genetic programming (GP), objectivefunctions are obtained by a terminating calculation. However,
the terminating calculation cannot evaluate distributed faulttolerant programs accurately. A key distinction in synthesizing distributed fault-tolerant programs is that they are inherently
non-deterministic, potentially having infinite computations andexecuting in an unpredictable environment. In this study, weapply a model checking technique - Binary Decision Diagrams(BDDs) - to GP, evaluating distributed programs by computing

Although Evolutionary Computation (EC) has been used withconsiderable success to evolve computer programs, the majority of this work has targeted the production of serial code. Recent work with Grammatical Evolution (GE) produced Multicore Grammatical Evolution (MCGE-II), a system that natively
produces parallel code, including the ability to execute recursive
calls in parallel. This paper extends this work by including practical constraints into the grammars and fitness functions, suchas increased control over the level of parallelism for each individual. These changes execute the best-of-generation programs
faster than the original MCGE-II with an average factor of 8.13
across a selection of hard problems from the literature. We analyze the time complexity of these programs and identify avoiding
excessive parallelism as a key for further performance scaling.
We amend the grammars to evolve a mix of serial and parallel112

code, which spawns only as many threads as is efficient given
the underlying OS and hardware; this speeds up execution by afactor of 9.97.
On the Bias of Syntactic Geometric Recombination in Genetic Programming and Grammatical Evolution

Abstracts

generation DNA sequences to the human genome using the
Burrows-Wheeler algorithm (BWA) on nVidia Tesla parallelgraphics hardware (GPUs). GI using phenotypic tabu searchwith manually grown code can graft new features giving morethan 100 fold speed up on a performance critical kernel without
loss of accuracy.

Ann Thorhauer, Franz Rothlauf
For fixed-length binary representations as used in genetic algorithms, standard recombination operators (e.g., one-pointcrossover) are unbiased. Thus, the application of recombination only reshuffles the alleles and does not change the statisticalproperties in the population. Using a geometric view on recombination operators, most search operators for fixed-length strings
are geometric, which means that the distances between offspring
and their parents are less than, or equal to, the distance between
their parents. In genetic programming (GP) and grammaticalevolution (GE), the situation is different since the recombination operators are applied to variable-length structures. Thus,
most recombination operators for GE and GP are not geometric.
This paper focuses on the bias of recombination in GE and GP
and studies whether the application of recombination alone produces specific types of solutions with a higher probability. We
consider two different types of recombination operators: standard recombination and syntactic geometric recombination. In
our experiments, we performed random walks through the binary tree search space and found that syntactic geometric recombination operators are biased and strongly reduce population
diversity. In a performance comparison, we found that syntactic geometric recombination leads to large fitness improvementsin the first generations, but that fitness converges after several
generations and no further search is possible.
GP3
General Program Synthesis Benchmark SuiteThomas Helmuth, Lee Spector
Recent interest in the development and use of non-trivial benchmark problems for genetic programming research has highlighted the scarcity of general program synthesis (also called“traditional programming”) benchmark problems. We present
a suite of 29 general program synthesis benchmark problems
systematically selected from sources of introductory computerscience programming problems. This suite is suitable for experiments with any program synthesis system driven by input/output
examples. We present results from illustrative experiments using
our reference implementation of the problems in the PushGP genetic programming system. The results show that the problems
in the suite vary in difficulty and can be useful for assessing thecapabilities of a program synthesis system.
Improving CUDA DNA Analysis Software with Genetic Programming
William Langdon, Brian Lam, Justyna Petke, Mark Harman
We genetically improve BarraCUDA using a BNF grammar
incorporating C scoping rules with GP. Barracuda maps next

Efficient Evolution of High Entropy RNGs Using Single
Node Genetic Programming
Philip Leonard, David Jackson
Random Number Generators are an important aspect of many
modern day software systems, cryptographic protocols and modelling techniques. To be more accurate, it is Pseudo Random
Number Generators (PRNGs) that are more commonly used overtheir expensive, and less practical hardware based counterparts.
Given that PRNGs rely on some deterministic algorithm (typically a Linear Congruential Generator) we can leverage Shannons theory of information as our fitness function in order togenerate these algorithms by evolutionary means. In this paper we compare traditional Genetic Programming (GP) against
its graph based implementation, Single Node Genetic Programming (SNGP), for this task. We show that with SNGPs uniqueprogram structure and use of dynamic programming, it is possible to obtain smaller, higher entropy PRNGs, over six times
faster and produced at a solution rate twice that achieved using Kozas standard GP model. We also show that the PRNGs
obtained from evolutionary methods produce higher entropy
outputs than other widely used PRNGs and Hardware RNGs
(specifically recordings of atmospheric noise), as well as surpassing them in a variety of other statistical tests presented in
the NIST RNG test suite.
A Re-Examination of the Use of Genetic Programming on
the Oral Bioavailability Problem
Grant Dick, Aysha Rimoni, Peter Whigham
Difficult benchmark problems are in increasing demand in Genetic Programming (GP). One problem seeing increased usageis the oral bioavailability problem, which is often presented asa challenging problem to both GP and other machine learning
methods. However, few properties of the bioavailability data
set have been demonstrated, so attributes that make it a challenging problem are largely unknown. This work uncovers important properties of the bioavailability data set, and suggeststhat the perceived difficulty in this problem can be partially attributed to a lack of pre-processing, including features within
the data set that contain no information, and contradictory relationships between the dependent and independent features ofthe data set. The paper then re-examines the performance of GP
on this data set, and contextualises this performance relative toother regression methods. Results suggest that a large component of the observed performance differences on the bioavailability data set can be attributed to variance in the selection oftraining and testing data. Differences in performance between
GP and other methods disappear when multiple training/testing
splits are used within experimental work, with performance typ-

Abstracts

ically no better than a null modelling approach of reporting themean of the training data.
GP4
An Efficient Structural Diversity Technique for Genetic Programming
Armand Burks, William Punch
Genetic diversity plays an important role in avoiding premature
convergence, which is a phenomenon that stifles the search effectiveness of evolutionary algorithms. However, approaches
that avoid premature convergence by maintaining genetic diversity can do so at the cost of efficiency, requiring more fitness
evaluations to find high quality solutions. We introduce a simple
and efficient genetic diversity technique that is capable of avoiding premature convergence while maintaining a high level ofsearch quality in tree-based genetic programming. Our methodfinds solutions to a set of benchmark problems in significantly
fewer fitness evaluations than the algorithms that we comparedagainst.
Genetic Programming with Epigenetic Local SearchWilliam La Cava, Thomas Helmuth, Lee Spector, KouroshDanai
We focus on improving genetic programming through local
search of the space of program structures using an inheritableepigenetic layer that specifies active and inactive genes. We explore several genetic programming implementations that represent the different properties that epigenetics can provide, suchas passive structure, phenotypic plasticity, and inheritable gene
regulation. We apply these implementations to several symbolic
regression and program synthesis problems. For the symbolic
regression problems, the results indicate that epigenetic local
search consistently improves genetic programming by producing smaller solution programs with better fitness. Furthermore,
we find that incorporating epigenetic modification as a mutation
step in program synthesis problems can improve the ability ofgenetic programming to find exact solutions. By analyzing population homology we show that the epigenetic implementations
maintain diversity in silenced portions of programs which may
provide protection from premature convergence.
Memetic Semantic Genetic Programming
Robyn Ffrancon, Marc Schoenauer
Semantic Backpropagation (SB) was introduced in GP so as totake into account the semantics of a GP tree at all intermediate
states of the program execution, i.e., at each node of the tree.
The idea is to compute the optimal ”should-be” values each subtree should return, whilst assuming that the rest of the tree isunchanged, so as to minimize the fitness of the tree. To this end,
the Random Desired Output (RDO) mutation operator, uses SB
in choosing, from a given library, a tree whose semantics are
preferred to the semantics of a randomly selected subtree fromthe parent tree. Pushing this idea one step further, this paper introduces the Brando (BRANDO) operator, which selects from113

the parent tree the overall best subtree for applying RDO, usinga small randomly drawn static library. Used within a simple Iterated Local Search framework, BRANDO can find the exact solution of many popular Boolean benchmarks in reasonable time
whilst keeping solution trees small, thus paving the road for truly
memetic GP algorithms.
Geometric Semantic Genetic Programming with Local
SearchMauro Castelli, Leonardo Trujillo, Leonardo Vanneschi, Sara
Silva, Emigdio Z-Flores, Pierrick LegrandSince its introduction, Geometric Semantic Genetic Programming (GSGP) has aroused the interest of numerous researchersand several studies have demonstrated that GSGP is able toeffectively optimize training data by means of small variation
steps, that also have the effect of limiting overfitting. In order tospeed up the search process, in this paper we propose a systemthat integrates a local search strategy into GSGP (called GSGPLS). Furthermore, we present a hybrid approach, that combines
GSGP and GSGP-LS, aimed at exploiting both the optimization
speed of GSGP-LS and the ability to limit overfitting of GSGP.
The experimental results we present, performed on a set of complex real-life applications, show that GSGP-LS achieves the best
training fitness while converging very quickly, but severely overfits. On the other hand, GSGP converges slowly relative to theother methods, but is basically not affected by overfitting. The
best overall results were achieved with the hybrid approach, allowing the search to converge quickly, while also exhibiting a
noteworthy ability to limit overfitting. These results are encouraging, and suggest that future GSGP algorithms should focus onfinding the correct balance between the greedy optimization ofa local search strategy and the more robust geometric semantic
operators.
GP5
Evolutionary Image Descriptor: A Dynamic Genetic Programming Representation for Feature Extraction
Harith Al-Sahaf, Mengjie Zhang, Mark Johnston
Texture classification aims at categorising instances that havea similar repetitive pattern. In computer vision, texture classification represents a fundamental element in a wide variety of
applications, which can be performed by detecting texture primitives of the different classes. Using image descriptors to detect prominent features has been widely adopted in computer
vision. Building an effective descriptor becomes more challenging when there are only a few labelled instances. This paper
proposes a new Genetic Programming (GP) representation forevolving an image descriptor that operates directly on the raw
pixel values and uses only two instances per class. The new
method synthesises a set of mathematical formulas that are used
to generate the feature vector, and the classification is then performed using a simple instance-based classifier. Determining
the length of the feature vector is automatically handled by the
new method. Two GP and nine well-known non-GP methods

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are compared on two texture image data sets for texture classification in order to test the effectiveness of the proposed method.
The proposed method is also compared to three hand-crafted descriptors namely domain-independent features, local binary patterns, and Haralick texture features. The results show that the
proposed method has superior performance over the competitive
methods.
Multiple Objective Vector-Based Genetic Programming Using Human-Derived Primitives
Jason Zutty, Daniel Long, Heyward Adams, Gisele Bennett,
Christina Baxter
Traditional genetic programming only supports the use of arithmetic and logical operators on scalar features. The GTMOEP(Georgia Tech Multiple Objective Evolutionary Programming)
framework builds upon this by also handling feature vectors, allowing the use of signal processing and machine learning functions as primitives, in addition to the more conventional operators. GTMOEP is a novel method for automated, data-driven
algorithm creation, capable of outperforming human derived solutions. As an example, GTMOEP was applied to the problem
of predicting how long an emergency responder can remain in ahazmat suit before the effects of heat stress cause the user to become unsafe. An existing third-party physics model was leveraged for predicting core temperature from various situationalparameters. However, a sustained high heart rate also meansthat a user is unsafe. To improve performance, GTMOEP was
evaluated to predict an expected pull time, computed from boththresholds during human trials. GTMOEP produced dominantsolutions in multiple objective space to the performance of predictions made by the physics model alone, resulting in a safer algorithm for emergency responders to determine operating times
in harsh environments. The program generated by GTMOEP
will be deployed to a mobile application for their use.

Abstracts

A GP-based Video Game Player
Baozhu Jia, Marc Ebner, Christian Schack
A general video game player is an an agent that can learn to playdifferent video games with no specific domain knowledge. We
are working towards developing a GP-based general video gameplayer. Our system currently extracts game state features fromscreen grabs. This information is then passed on to the gameplayer. Fitness is computed from data obtained directly fromthe internals of the game simulator. For this paper, we compare
three different types of game state features. These features differ
in how they describe the position to the nearest object surrounding the player. We have tested our genetic programming gameplayer system on three games: Space Invaders, Frogger and Missile Command. Our results show that a playing strategy for eachgame can be found efficiently for all three representations.
GEFPSO: A Framework for PSO Optimization based on
Grammatical EvolutionPéricles Miranda, Ricardo Prudéncio
In this work, we propose a framework to automatically generate
effective PSO designs by adopting Grammatical Evolution (GE).
In the proposed framework, GE searches for adequate structures and parameter values (e.g., acceleration constants, velocity
equations and different particles’ topology) in order to evolve
the PSO design. For this, a high-level Backus-Naur Form (BNF)
grammar was developed, representing the search space of possible PSO designs. In order to verify the performance of the
proposed method, we performed experiments using 16 diverse
continuous optimization problems, with different levels of difficulty. In the performed experiments, we identified the parameters and components that most affected the PSO performance, as
well as identified designs that could be reused across different
problems. We also demonstrated that the proposed method generates useful designs which achieved competitive solutions whencompared to well succeeded algorithms from the literature.

Hot Off the Press
HOP1
Beyond Pheromones: Evolving Error-Tolerant, Flexible, andScalable Ant-Inspired Robot Swarms
Joshua P. Hecker, Melanie E. Moses
For robot swarms to operate outside of the laboratory in complex real-world environments, they require the kind of error tolerance, flexibility, and scalability seen in living systems. Whilerobot swarms are often designed to mimic some aspect of the
behavior of social insects or other organisms, no systems have
yet addressed all of these capabilities in a single framework. We
describe a swarm robotics system that emulates ant behaviors
which govern memory, communication, and movement, as wellas an evolutionary process that tailors those behaviors into foraging strategies that maximize performance under varied andcomplex conditions. The system evolves appropriate solutions

to different environmental challenges. Solutions include: i) increased communication when sensed information is reliable andresources to be collected are highly clustered, ii) less communication and more individual memory when cluster sizes are variable, and iii) greater dispersal with increasing swarm size. Analysis of the evolved behaviors reveals the importance of interactions among behaviors, and of the interdependencies between
behaviors and environments. The effectiveness of interacting behaviors depends on the uncertainty of sensed information, the resource distribution, and the swarm size. Such interactions could
not be manually specified, but are effectively evolved in simulation and transferred to physical robots. This work is the first to
demonstrate high-level robot swarm behaviors that can be automatically tuned to produce efficient collective foraging strategies
in varied and complex environments.

Abstracts

Genotype Coding, Diversity, and Dynamic Evolutionary
Neural Network Environments: A Study on an Multi-agent
SystemJaime Davila
This paper reports the effects that different coding schemes at thegenetic level have on the evolution of neural network multi-agent
systems that operate under dynamic (changing) environments.
Types of NN encoding include direct encoding of weights andthree different L-Systems. Empirical results show that even variations within the same type of coding scheme can have considerable effects on evolution. Several different analysis of both
genotypes and phenotypes are used in order to explain the differences caused by the coding schemes.
Generalized Decomposition and Cross Entropy Methods for
Many-Objective Optimization
Ioannis Giagkiozis, Robin C. Purshouse, Peter J. Fleming

115

the Chebyshev scalarizing function, over Pareto-based methods.
We find that, under mild conditions on the objective function,
the Chebyshev scalarizing function has an almost identical effectto Pareto-dominance relations when we consider the probabilityof finding superior solutions for algorithms that follow a balanced trajectory. We propose the hypothesis that this seemingly
contradicting result compared with currently available empirical evidence, signals that the disparity in performance between
Pareto-based and decomposition-based methods is due to the inability of the former class of algorithms to follow a balanced
trajectory. We also link generalized decomposition to the resultsin this work and show how to obtain optimal scalarizing functions for a given problem, subject to prior assumptions on the
Pareto front geometry.
HOP2
Evolutionary Approach to Approximate Digital Circuits Design

Decomposition-based algorithms for multi-objective optimization problems have increased in popularity in the past decade.
Although convergence to the Pareto optimal front (PF) for suchalgorithms can often be superior to that of Pareto-based alternatives, the problem of effectively distributing Pareto optimal solutions in a high-dimensional space has not been solved. In thiswork, we introduce a novel concept which we call generalized
decomposition. Generalized decomposition provides a framework with which the decision maker (DM) can guide the underlying search algorithm toward specific regions of interest, or theentire Pareto front, with the desired distribution of Pareto optimal solutions. The method simplifies many-objective problems
by unifying the three performance objectives of an a posteriori
multi-objective optimizer – convergence to the PF, evenly distributed Pareto optimal solutions and coverage of the entire front– to only one, that of convergence. A framework, established on
generalized decomposition, and an estimation of distribution algorithm (EDA) based on low-order statistics, namely the crossentropy method, is created to illustrate the benefits of the proposed concept for many-objective problems. The algorithm –MACE-gD – is shown to be highly competitive with the existing
best-in-class decomposition-based algorithm (MOEA/D) and amore elaborate EDA method (RM-MEDA).

Zdenek Vasicek and Lukas Sekanina

Methods for Multi-Objective Optimization: An Analysis

Alma A. M. Rahat, Richard M. Everson, Jonathan E. Fieldsend

Ioannis Giagkiozis, Peter J. Fleming

Mesh network topologies are becoming increasingly popular inbattery powered wireless sensor networks, primarily due to theextension of network range. However, multi-hop mesh networks
suffer from higher energy costs, and the routing strategy employed directly affects the lifetime of nodes with limited energy resources. Hence when planning routes there are tradeoffs to be considered between individual and system-wide battery lifetimes. We present a multi-objective routing optimisation
approach using hybrid evolutionary algorithms to approximate
the optimal trade-off between minimum lifetime and the average lifetime of nodes in the network. In order to accomplish
this combinatorial optimisation rapidly, our approach prunes theDecomposition-based methods are often cited as the solution
to multi-objective nonconvex optimization problems with an increased number of objectives. These methods employ a scalarizing function to reduce the multi-objective problem into a setof single objective problems, which upon solution yield a good
approximation of the set of optimal solutions. This set is commonly referred to as Pareto front. In this work we explore the implications of using decomposition-based methods over Paretobased methods on algorithm convergence from a probabilistic
point of view. Namely, we investigate whether there is an advantage of using a decomposition-based method, for example using

In approximate computing, the requirement of perfect functional
behavior can be relaxed because some applications are inherently error resilient. Approximate circuits, which fall into theapproximate computing paradigm, are designed in such a waythat they do not fully implement the logic behavior given by
the specification and hence their accuracy can be exchanged forlower area, delay or power consumption. In order to automate
the design process, we propose to evolve approximate digital
circuits which show a minimal error for a supplied amount of
resources. The design process which is based on Cartesian Genetic Programming (CGP) can be repeated many times in orderto obtain various tradeoffs between the accuracy and area. A
heuristic seeding mechanism is introduced to CGP which allows
for improving not only the quality of evolved circuits, but also
reducing the time of evolution. The efficiency of the proposed
method is evaluated for the gate as well as the functional level
evolution. In particular, approximate multipliers and mediancircuits which show very good parameters in comparison withother available implementations were constructed by means of
the proposed method.
Hybrid Evolutionary Approaches to Maximum Lifetime
Routing and Energy Efficiency in Sensor Mesh Networks

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search space using k-shortest path pruning and a graph reduction
method which finds candidate routes promoting long minimum
lifetimes. When arbitrarily many routes from a node to the basestation are permitted, optimal routes may be found as the solution to a well-known linear program. We present an evolutionary
algorithm that finds good routes when each node is allowed onlya small number of paths to the base station. This algorithm uses
an evolutionary algorithm to propose new paths and a linear program to discover the optimum proportion of time that each pathshould be active. We show how employing separate optimisations in the two pruned search spaces before combining them ina final optimisation in the combination of the spaces is more effective than a single optimisation in the combined space. On areal network deployed in the Victoria & Albert Museum, London, these solutions, using only three paths per node, are able toachieve minimum lifetimes of over 99% of the optimum linear
program solution’s time to first sensor battery failure.
Learning to Anticipate Flexible Choices in Multiple Criteria
Decision-Making Under Uncertainty
Carlos R. B. Azevedo, Fernando J. Von Zuben
In several applications, a solution must be selected from a setof tradeoff alternatives for operating in dynamic and noisy environments. In this paper, such multicriteria decision process
is handled by anticipating flexible options predicted to improvethe decision maker future freedom of action. A methodology isthen proposed for predicting tradeoff sets of maximal hypervolume, where a multiobjective metaheuristic was augmented witha Kalman filter and a dynamical Dirichlet model for tracking andpredicting flexible solutions. The method identified decisions
that were shown to improve the future hypervolume of tradeoff
investment portfolio sets for outofsample stock data, when compared to a myopic strategy. Anticipating flexible portfolios was asuperior strategy for smoother changing artificial and realworld
scenarios, when compared to always implementing the decisionof median risk and to randomly selecting a portfolio from theevolved anticipatory stochastic Pareto frontier, whereas the median choice strategy performed better for abruptly changing markets. Correlations between the portfolio compositions and future
hypervolume were also observed.
Evolving computational solutions with carbon nanotube device
Julian F. Miller, Kester D. Clegg, Maktuba Mohid
We report for the first time on discovering solutions to two wellknown classes of computational problems using hybrid “in materio” computation. Evolution-in-materio is a technique thatuses evolutionary algorithms to search for configurations ofphysical materials that can carry out computation. The work was
published in two papers in Parallel Problem Solving from Nature(PPSN) in September 2014. The papers described how the EIM
technique was applied to two well-known classes of problem:
the travelling salesman problem (TSP) and data classification.
The latter paper was nominated for the best paper award. The
computational device used in these works consists of a single-

Abstracts

walled carbon nanotube / polymer composite material deposited
on a micro-electrode array. This is the first time that evolutionary algorithms have been used to configure a carbon nanotube
device to solve computational problems. The work is exciting
because it shows that evolution can be used to search materials to perform computation without a detailed understanding of
the internal physics of the devices. This may lead to entirely
new ways of solving computational problems. Following Arthur
Samuel we try to make materials do what is needed to be done,
without being told exactly how to do it.
HOP3
Artificial Immune System driven evolution in Swarm Chemistry
Emma Hart, Nicola Capodieci, Giacomo Cabri
Morphogenetic engineering represents an interesting field inwhich models, frameworks and algorithms can be tested in orderto study how self-* properties and emergent behaviours can arisein potentially complex and distributed systems. In this field, themorphogenetic model we will refer to is swarm chemistry, since
a well known challenge in this dynamical process concerns discovering mechanisms for providing evolution within coalescing
systems of particles. These systems consist in sets of moving
particles able to self-organise in order to create shapes or geometrical formations that provide robustness towards external
perturbations. We present a novel mechanism for providing evolutionary features in swarm chemistry that takes inspiration from
artificial immune system literature, more specifically regarding
idiotypic networks. Starting from a restricted set of chemical
recipes, we show that the system evolves to new states, using
an autonomous method of detecting new shapes and behaviours
free from any human interaction.
Incorporating Dynamism in Emergency Route Planning
Problem using Immune-Based Approach
Mohd Nor Akmal Khalid, Umi Kalsom Yusof
The occurrence of emergency events tends to spark a very
chaotic reaction, inducing a large surge of demand (number of evacuees) which exceeds the available resources (pathway/network). Planning a suitable evacuation route and identifying the shortest evacuation route before the occurrence of extreme events are crucial for an effective evacuation process. Although evacuation plans can be orchestrated in advance, probable crowd dynamics, especially group-based characteristics(e.g. group formation, group relation, group competition, etc.),
may occur, often rendering unfeasible evacuation plan. Therefore, creating a dynamic and effective emergency route planning (ERP) approach is of utmost importance. Various ERP
approaches have been proposed, which includes mathematicalbased approach, heuristic-driven approach, and meta-heuristic
approach. The lack of meta-heuristic approaches in the domain
of ERP problem, although its capability of handling dynamic
constraints and produces optimum result, serve as an encouragement of applying this approach. Therefore, an integrated evacu-

Abstracts

ation planning with dynamism (iEvaP+) approach is proposed tocater the dynamic of groups in crowd and optimizing the routeselection mechanism, where the use of immune-based metaheuristic approach had effectively produces reliable results (average percentage difference of the best solution is about 54.14%)
Gene Regulatory Network Evolution Through Augmenting
Topologies
Sylvain Cussat-Blanc, Kyle Harrington, Jordan Pollack
Artificial gene regulatory networks are biologically-inspired dynamical systems used to control various kinds of agents, fromthe cells in developmental models to embodied robot swarms.
Most recent work uses a genetic algorithm or an evolution strategy in order to optimize the network for a specific task. However, the empirical performances of these algorithms are unsatisfactory. This paper presents an algorithm that primarily exploits
a network distance metric which allows genetic similarity to be
used for speciation and variation of gene regulatory networks.
This algorithm, inspired by the successful neuroevolution ofaugmenting topologies (NEAT) algorithm’s use in evolving neural networks and compositional pattern-producing networks, isbased on a specific initialization method, a crossover operator
based on gene alignment, and speciation based upon gene regulatory network structures. We demonstrate the effectiveness of
this new algorithm by comparing our approach both to a standard
genetic algorithm and to evolutionary programming on four different experiments from three distinct problem domains, where
the proposed algorithm excels on all experiments.
ExSTraCS 2.0: Description and Evaluation of a Scalable
Learning Classifier System
Ryan Urbanowicz, Jason Moore
Algorithmic scalability is a major concern for any machinelearning strategy in this age of ‘big data’. A large number of potentially predictive attributes is emblematic of problems in bioinformatics, genetic epidemiology, and many other fields. Previously, ExSTraCS was introduced as an extended Michiganstyle supervised learning classifier system that combined a setof powerful heuristics to successfully tackle the challenges ofclassification, prediction, and knowledge discovery in complex,
noisy, and heterogeneous problem domains. While Michiganstyle learning classifier systems are powerful and flexible learners, they are not considered to be particularly scalable. For
the first time, this paper presents a complete description of the
ExSTraCS algorithm and introduces an effective strategy to dramatically improve learning classifier system scalability. ExSTraCS 2.0 addresses scalability with (1) a rule specificity limit,(2) new approaches to expert knowledge guided covering andmutation mechanisms, and (3) the implementation and utilization of the TuRF algorithm for improving the quality of expert
knowledge discovery in larger datasets. Performance over acomplex spectrum of simulated genetic datasets demonstrated
that these new mechanisms dramatically improve nearly every
performance metric on datasets with 20 attributes and made it
possible for ExSTraCS to reliably scale up to perform on re-117

lated 200 and 2000-attribute datasets. ExSTraCS 2.0 was alsoable to reliably solve the 6, 11, 20, 37, 70, and 135 multiplexer
problems, and did so in similar or fewer learning iterations thanpreviously reported, with smaller finite training sets, and without using building blocks discovered from simpler multiplexer
problems. Furthermore, ExSTraCS usability was made simpler
through the elimination of previously critical run parameters.
HOP4
The effects of asymmetric neighborhood assignment in the
MOEA/D algorithm
Krzysztof Michalak
The Multiobjective Evolutionary Algorithm Based on Decomposition (MOEA/D) is a very efficient multiobjective evolutionary algorithm introduced in recent years. This algorithm works
by decomposing a multiobjective optimization problem to many
scalar optimization problems and by assigning each specimen in
the population to a specific subproblem. The MOEA/D algorithm transfers information between specimens assigned to thesubproblems using a neighborhood relation. In this paper it isshown that parameter settings commonly used in the literaturecause an asymmetric neighbor assignment which in turn affects
the selective pressure and consequently causes the population toconverge asymmetrically. The paper contains theoretical explanation of how this bias is caused as well as an experimental verification. The described effect is undesirable, because a multiobjective optimizer should not introduce asymmetries not present
in the optimization problem. The paper gives some guidelines
on how to avoid such artificial asymmetries.
Shift-Based Density Estimation for Pareto-Based Algorithms in Many-Objective Optimization
Miqing Li, Shengxiang Yang, Xiaohui Liu
It is commonly accepted that Pareto-based evolutionary multiobjective optimization (EMO) algorithms encounter difficulties
in dealing with many-objective problems. In these algorithms,
the ineffectiveness of the Pareto dominance relation for a highdimensional space leads diversity maintenance mechanisms toplay the leading role during the evolutionary process, while thepreference of diversity maintenance mechanisms for individuals
in sparse regions results in the final solutions distributed widelyover the objective space but distant from the desired Pareto front.
Intuitively, there are two ways to address this problem: 1) modifying the Pareto dominance relation and 2) modifying the diversity maintenance mechanism in the algorithm. In this paper,
we focus on the latter and propose a shift-based density estimation (SDE) strategy. The aim of our study is to develop a general modification of density estimation in order to make Paretobased algorithms suitable for many-objective optimization. In
contrast to traditional density estimation that only involves the
distribution of individuals in the population, SDE covers both
the distribution and convergence information of individuals. The
application of SDE in three popular Pareto-based algorithms
demonstrates its usefulness in handling many-objective prob-

118

Abstracts

lems. Moreover, an extensive comparison with five state-ofthe-art EMO algorithms reveals its competitiveness in balancing
convergence and diversity of solutions. These findings not only
show that SDE is a good alternative to tackle many-objective
problems, but also present a general extension of Pareto-basedalgorithms in many-objective optimization.

competitive results in both competitions, showing its potential
for solving time series classification problems. The main advantage of our serial processing approach is that it can easily handle
very large data sets.

Genetic programming and serial processing for time seriesclassification

Thomas Helmuth, Lee Spector, James Matheson

Eva Alfaro-Cid, Ken Sharman, Anna I. Esparcia-Alcázar
This work describes an approach devised by the authors for timeseries classification. In our approach genetic programming isused in combination with a serial processing of data, where thelast output is the result of the classification. The use of genetic
programming for classification, although still a field where more
research in needed, is not new. However, the application of genetic programming to classification tasks is normally done byconsidering the input data as a feature vector. That is, to thebest of our knowledge, there are not examples in the genetic programming literature of approaches where the time series data areprocessed serially and the last output is considered as the classification result. The serial processing approach presented here
fills a gap in the existing literature. This approach was tested
in three different problems. Two of them are real world problems whose data were gathered for on-line or conference competitions. As there are published results of these two problems
this gives us the chance of comparing the performance of ourapproach against top performing methods. The serial processing of data in combination with genetic programming obtained

Solving Uncompromising Problems with Lexicase Selection

We describe a broad class of problems, called uncompromising problems, characterized by the requirement that solutions
must perform optimally on each of many test cases. Many ofthe problems that have long motivated genetic programming research, including the automation of many traditional programming tasks, are uncompromising. We describe and analyze therecently proposed lexicase parent selection algorithm and showthat it can facilitate the solution of uncompromising problems by
genetic programming. Unlike most traditional parent selection
techniques, lexicase selection does not base selection on a fitness value that is aggregated over all test cases; rather, it considers test cases one at a time in random order. We present resultscomparing lexicase selection to more traditional parent selection methods, including standard tournament selection and implicit fitness sharing, on four uncompromising problems: finding terms in finite algebras, designing digital multipliers, counting words in files, and performing symbolic regression of thefactorial function. We provide evidence that lexicase selection
maintains higher levels of population diversity than other selection methods, which may partially explain its utility as a parent
selection algorithm in the context of uncompromising problems.

Integrative Genetic and Evolutionary Computation
IGEC
Knowledge Transfer from Keepaway Soccer to Half-field Offense through Program Symbiosis: Building Simple Programs for a Complex Task

same level of play in HFO.
A Local Search Approach to Genetic Programming for Binary Classification

Stephen Kelly, Malcolm Heywood

Emigdio Z-Flores, Leonardo Trujillo, Oliver Schütze, Pierrick
LegrandHalf-field Offense (HFO) is a sub-task of Robocup 2D Simulated Soccer. HFO is a challenging, multi-agent machine learning problem in which a team of offense players attempt to manoeuvre the ball past a defending team and around the goalie
in order to score. The agent’s sensors and actuators are noisy,
making the problem highly stochastic and partially observable.
These same real-world characteristics have made Keepaway soccer, which represents one sub-task of HFO, a popular testbed in
the reinforcement learning and task-transfer literature in particular. We demonstrate how policies initially evolved for Keepaway
can be reused within a symbiotic framework for coevolving policies in genetic programming (GP), with no additional trainingor transfer function, in order to improve learning in the HFO
task. Moreover, the highly modular policies discovered by GP
are shown to be significantly less complex than solutions basedon traditional value-function optimization while achieving the

In standard genetic programming (GP), a search is performed
over a syntax space defined by the set of primitives, looking forthe best expressions that minimize a cost function based on a
training set. However, most GP systems lack a numerical optimization method to fine tune the implicit parameters of each candidate solution. Instead, GP relies on more exploratory search
operators at the syntax level. This work proposes a memetic
GP, tailored for binary classification problems. In the proposed
method, each node in a GP tree is weighted by a real-valued
parameter, which is then numerically optimized using a continuous transfer function and the Trust Region algorithm is used
as a local search method. Experimental results show that potential classifiers produced by GP are improved by the local
searcher, and hence the overall search is improved achieving
significant performance gains, that are competitive with stateof-the-art methods on well-known benchmarks.

Abstracts

Evolving Strategies for Social Innovation Games
Erkin Bahceci, Riitta Katila, Risto Miikkulainen
While evolutionary computation is well suited for automatic discovery in engineering, it can also be used to gain insight into
how humans and organizations could perform more effectively
in competitive problem-solving domains. This paper formalizes human creative problem solving as competitive multi-agent
search, and advances the hypothesis that evolutionary computation can be used to discover effective strategies for it. In experiments in a social innovation game (similar to a fantasy sports

119

league), neural networks were first trained to model individual
human players. These networks were then used as opponents to
evolve better game-play strategies with the NEAT neuroevolution method. Evolved strategies scored significantly higher thanthe human models by innovating, retaining, and retrieving lessand by imitating more, thus providing insight into how performance could be improved in such domains. Evolutionary computation in competitive multi-agent search thus provides a possible framework for understanding and supporting various humancreative activities in the future.

Parallel Evolutionary Systems
PES1
Fast Knowledge Discovery in Time Series with GPGPU on
Genetic Programming
Sungjoo Ha, Byung-Ro Moon
We tackle the problem of knowledge discovery in time series
data using genetic programming and GPGPUs. Using genetic
programming, various precursor patterns that have certain attractive qualities are evolved to predict the events of interest.
Unfortunately, evolving a set of diverse patterns typically takes
huge execution time, sometimes longer than one month for thiscase. In this paper, we address this problem by proposing a parallel GP framework using GPGPUs, particularly in the context
of big financial data. By maximally exploiting the structure of
the nVidia GPGPU platform on stock market time series data,
we were able see more than 250-fold reduction in the running
time.

PES2
Injection, Saturation and Feedback in Meta-Heuristic Interactions
Krzysztof Nowak, Dario Izzo, Daniel Hennes
Meta-heuristics have proven to be an efficient method of handling difficult global optimization tasks. A recent trend in evolutionary computation is the use of several meta-heuristics at thesame time, allowing for occasional information exchange among
them in hope to take advantage from the best algorithmic properties of all. Such an approach is inherently parallel and, withsome restrictions, has a straight forward implementation in aheterogeneous island model. We propose a methodology forcharacterizing the interplay between different algorithms, andwe use it to discuss their performance on real-parameter single
objective optimization benchmarks. We introduce the new concepts of feedback, saturation and injection, and show how they
are powerful tools to describe the interplay between different algorithms and thus to improve our understanding of the internalmechanism at work in large parallel evolutionary set-ups.

Real World Applications
RWA1
Genetic Programming for Estimation of Heat Flux between
the Atmosphere and Sea Ice in Polar Regions
Karolina Stanislawska, Krzysztof Krawiec, Timo Vihma
The Earth surface and atmosphere exchange heat via turbulent
fluxes. An accurate description of the heat exchange is essential in modelling the weather and climate. In these models theheat fluxes are described applying the Monin-Obukhov similarity theory, where the flux depends on the air-surface temperature
difference and wind speed. The theory makes idealized assumptions and the resulting estimates often have large errors. This is
the case particularly in conditions when the air is warmer thanthe Earth surface, i.e., the atmospheric boundary layer is stably stratified, and turbulence is therefore weak. This is a common situation over snow and ice in the Arctic and Antarctic. In

this paper, we present alternative models for heat flux estimation
evolved by means of genetic programming (GP). To this aim, we
utilize the best heat flux data collected in the Arctic and Antarctic sea ice zones. We obtain GP models that are more accurate,robust, and conceptually novel from the viewpoint of meteorology. Contrary to the Monin-Obukhov theory, the GP equations
are not solely based on the air-surface temperature difference
and wind speed, but include also radiative fluxes that improve
the performance of the method. These results open the door toa new class of approaches to heat flux prediction with potential
applications in weather and climate models.

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On Evolutionary Approaches to Wind Turbine Placementwith Geo-Constraints
Daniel Lückehe, Markus Wagner, Oliver Kramer
Wind turbine placement, i.e., the geographical planning of windturbine locations, is an important first step to an efficient integration of wind energy. The turbine placement problem becomes adifficult optimization problem due to varying wind distributions
at different locations and due to the mutual interference in thewind field known as wake effect. Artificial and environmental
geological constraints make the optimization problem even moredifficult to solve. In our paper, we focus on the evolutionary turbine placement based on an enhanced wake effect model fed
with real-world wind distributions. We model geo-constraints
with real-world data from OpenStreetMap. Besides the realistic
modeling of wakes and geo-constraints, the focus of the paper
is on the comparison of various evolutionary optimization approaches. We propose four variants of evolution strategies withturbine-oriented mutation operators and compare to state-of-theart optimizers like the CMA-ES in a detailed experimental analysis on three benchmark scenarios.
Efficient Sampling of PI Controllers in Evolutionary Multiobjective Optimization
Gilberto Reynoso-Meza, Leandro dos Santos Coelho, Roberto
Z. Freite
Proportional-Integral (PI) controllers remain as a practical andreliable solution for multivariable control for several industrial
applications. Efforts to develop new tuning techniques fulfilling
several performance indicators and guaranteeing robustness areworthwhile. Evolutionary multiobjective optimization (EMO)
has been used for multivariable PI controller tuning, due to theirflexibility and its advantages to depict the trade off among conflicting objectives. It is a regular practice bounding the search
space as a hyperbox; nevertheless, the shape of the feasible spaceof PI parameters which are internally stable for a given control
loop is irregular. Therefore, such hyperbox could enclose feasible and unfeasible solutions or contain a subset of the feasible
set. In the former case, convergence capabilities of an algorithm
could be compromised; in the latter case, search space is not
fully explored. In this work, a coding mechanism is proposedin order to explore more efficiently the PI parameters feasible
set (that is, all feasible solutions and only feasible solutions) in
EMO. With the example provided, the advantages to approximate a Pareto front for 2, 3 and 5 objectives are shown, validating the mechanism as useful for EMO in multivariable PIcontroller tuning.
Diversifying Multi-Objective Gradient Techniques and their
Role in Hybrid Multi-Objective Evolutionary Algorithms for
Deformable Medical Image Registration
Kleopatra Pirpinia, Tanja Alderliesten, Jan-Jakob Sonke, Marcel
van Herk, Peter Bosman
Gradient methods and their value in single-objective, real-valued
optimization are well-established. As such, they play a key

Abstractsrole in tackling real-world, hard optimization problems suchas deformable image registration (DIR). A key question is towhich extent gradient techniques can also play a role in a multiobjective approach to DIR. We therefore aim to exploit gradient information within an evolutionary-algorithm-based multiobjective optimization framework for DIR. Although an analytical description of the multi-objective gradient (the set of all
Pareto-optimal improving directions) is available, it is nontrivial how to best choose the most appropriate direction per solution because these directions are not necessarily uniformly
distributed in objective space. To address this, we employ aMonte-Carlo method to obtain a discrete, spatially-uniformly
distributed approximation of the set of Pareto-optimal improving
directions. We then apply a diversification technique in which
each solution is associated with a unique direction from this set
based on its multi- as well as single-objective rank. To assess
its utility, we compare a state-of-the-art multi-objective evolutionary algorithm with three different hybrid versions thereof on
several benchmark problems and two medical DIR problems.
Results show that the diversification strategy successfully leads
to unbiased improvement, helping an adaptive hybrid scheme
solve all problems, but the evolutionary algorithm remains themost powerful optimization method, providing the best balance
between proximity and diversity.
RWA2
A Closer Look At Differential Evolution For The Optimal
Well Placement Problem
Grazieli Carosio, Thomas Humphries, Ronald Haynes, Colin
Farquharson
Energy demand has increased considerably with the growth ofworld population, increasing the interest in the hydrocarbon
reservoir management problem. Companies are concerned withmaximizing oil recovery while minimizing capital investment
and operational costs. A first step in solving this problem is
to consider optimal well placement. In this work, we investigate the Differential Evolution (DE) optimization method, using
distinct configurations with respect to population size, mutation
factor, crossover probability, and mutation strategy, to solve thewell placement problem. By assuming a bare control procedure,
one optimizes the parameters representing positions of injection
and production wells. The Tenth SPE Comparative Solution
Project and MATLAB Reservoir Simulation Toolbox (MRST)
are the benchmark dataset and simulator used, respectively. The
goal is to evaluate the performance of DE in solving this important real-world problem. We show that DE can find high-quality
solutions, when compared with a reference from the literature,
and a preliminary analysis on the results of multiple experiments
gives useful information on how DE configuration impacts its
performance.

Abstracts

121

Selecting Best Investment Opportunities from Stock Portfolios Optimized by a Multiobjective Evolutionary Algorithm
Krzysztof Michalak

Evolving Solutions to TSP Variants for Active Space Debris
RemovalMultiobjective optimization of portfolios aims at finding setsof stocks which are expected to provide a possibly high return
while retaining a moderate level of risk. The Pareto front of portfolios generated by the optimization algorithm represents attainable trade-offs between returns obtained by the portfolios andthe level of risk involved in the investment. This paper studies the relationship between location of portfolios in the Pareto
front and future returns of these portfolios. It is observed thatthe highest future returns can be obtained for the portfolios withthe highest return and risk measures observed in the past but also
for those with the lowest return and risk in the Pareto front. Neither constantly selecting portfolios with high return on historical
data nor, conversely, those with low historical risk (but also low
return) yields high future returns. Based on these observations
a method is proposed for adaptively selecting the best portfolios
for investment from solutions contained in the Pareto front. The
proposed method selects high-return (but also high-risk) portfolios or low-risk (but also low-return) portfolios based on the
behaviour of the stock marked index in the time period preceding the moment of investment. The proposed method outperforms both the strategy of always selecting the portfolios withthe highest return from the past and the risk-averse strategy of
selecting portfolios with low risk measure.

The space close to our planet is getting more and more polluted.
Orbiting debris are posing an increasing threat to operational orbits and the cascading effect, known as Kessler syndrome, may
result in a future where the risk of orbiting our planet at some altitudes will be unacceptable. Many argue that the debris density
at the Low Earth Orbit (LEO) has already reached a level sufficient to trigger such a cascading effect. An obvious consequenceis that we may soon have to actively clean space from debris.
Such a space mission will involve a complex combinatorial decision as to choose which debris to remove and in what order. In
this paper, we find that this part of the design of an active debris
removal mission (ADR) can be mapped into increasingly complex variants to the classic Travelling Salesman Problem (TSP)and that they can be solved by the Inver-over algorithm improving the current state-of-the-art in ADR mission design. We define static and dynamic cases, according to whether we consider
the debris orbits as fixed in time or subject to orbital perturbations. We are able, for the first time, to select optimally objects
from debris clouds of considerable size: hundreds debris pieces
considered while previous works stopped at tens.

Exploiting Linkage Information and Problem-SpecificKnowledge in Evolutionary Distribution Network Expansion Planning
Ngoc Hoang Luong, Han La Poutré, Peter Bosman
This paper tackles the Distribution Network Expansion Planning(DNEP) problem that has to be solved by distribution network
operators to decide which, where, and/or when enhancements
to electricity networks should be introduced to satisfy the future power demands. We compare two evolutionary algorithms(EAs) for optimizing expansion plans: the classic genetic algorithm (GA) with uniform crossover and the Gene-pool Optimal
Mixing Evolutionary Algorithm (GOMEA) that learns and exploits linkage information between problem variables. We study
the impact of incorporating different levels of problem-specificknowledge in the variation operators as well as two constrainthandling techniques: constraint domination and repair mechanisms. Experiments show that the use of problem-specific variation operators is far more important for the classic GA to findhigh-quality solutions to the DNEP problem. GOMEA is foundto have far more robust performance even when an out-of-box
variant is used that doesn’t exploit problem-specific knowledge.
Based on experiments, we suggest that when selecting optimization algorithms for real-world applications like DNEP, EAs thathave the ability to model and exploit problem structures, suchas GOMEAs and estimation-of-distribution algorithms, should
be given priority, especially when problem-specific knowledge
is not straightforward to exploit, e.g. in the case of black-box
optimization.

Dario Izzo, Ingmar Getzner, Daniel Hennes, Luı́s Simões

RWA3
Using Multi-Objective Artificial Immune Systems to Find
Core Collections Based on Molecular Markers
Shana Schlottfeldt, Maria Emilia Walter, Jon Timmis, Andre
Carvalho, Mariana Telles, Jose Alexandre Diniz-Filho
Germplasm collections are an important strategy for conservation of diversity, a challenge in ecoinformatics. It is common to
select a core to represent the genetic diversity of a germplasm
collection, aiming to minimize the costs of conservation, while
ensuring the maximization of genetic variation. For the problem of finding a core for a germplasm collection, we proposed
the use of a constrained multi-objective artificial immune algorithm (MAIS), based on principles of systematic conservation
planning (SCP), and incorporating heterozygosity information.
Therefore, optimization takes genotypic diversity and variability
patterns into account. As a case study, we used Dipteryx alata
molecular marker information. We were able to identify withinseveral accessions, the exact entries that should be chosen topreserve species diversity. MAIS presented better performancemeasure results when compared to NSGA-II. The proposed approach can be used to help construct cores with maximal genetic
richness, and also be extended to in situ conservation. As far as
we know, this is the first time that an AIS algorithm is applied tothe problem of finding a core for a germplasm collection using
heterozygosity information as well.

122

Smart Mobility Policies with Evolutionary Algorithms: The
Adapting Info Panel Case
Daniel Stolfi, Enrique Alba
In this article we propose the Yellow Swarm architecture for
reducing travel times, greenhouse gas emissions and fuel consumption of road traffic by using several LED panels to suggest
changes in the direction of vehicles (detours) for different timeslots. These time intervals are calculated using an evolutionary
algorithm, specifically designed for our proposal, which evaluates many working scenarios based on real cities, imported fromOpenStreetMap into the SUMO traffic simulator. Our results
show an improvement in average travel times, emissions, andfuel consumption even when only a small percentage of drivers
follow the indications provided by our panels.
An Integrated Approach to Stage 1 Breast Cancer Detection
Jeannie Fitzgerald, Conor Ryan, David Medernach, Krzysztof
Krawiec
We present an automated, end-to-end approach for Stage 1
breast cancer detection. The first phase of our proposed workflow takes individual digital mammograms as input and outputs
several smaller sub-images from which the background has been
removed. Next, we extract a set of features which capture textural information from the segmented images. In the final phase,the most salient of these features are fed into a Multi-Objective
Genetic Programming system which then evolves classifiers capable of identifying those segments which may have suspicious
areas that require further investigation. A key aspect of this workis the examination of several new experimental configurations
which focus on textural asymmetry between breasts. The best
evolved classifier using such a configuration can deliver resultsof 100% accuracy on true positives and a false positive per image rating of just 0.33, which is better than the current state of
the art.
Finding an Optimal LEGO(R) Brick Layout of Voxelized 3D
Object Using a Genetic Algorithm
Sangyeop Lee, Jinhyun Kim, Jae Woo Kim, Byung-Ro Moon
In this paper, we propose a genetic algorithm for a LEGO(R)brick layout problem. The task is to build a given 3D object
with LEGO(R) bricks. A brick layout is modeled as a solution
to a combinatorial optimization problem, through intermediate
voxelization, which tries to maximize the connectivity and thenminimize the number of used bricks. We attack the problem inthe context of genetic search. The proposed randomized greedy
algorithm produces initial solutions, and the solutions are effectively improved by an evolutionary process. New domainspecific methods are proposed as well, which include a randomboundary mutation and a thickening approach. We tested ouralgorithm on various objects collected from the web. Experimental results showed that the algorithm produces efficient, andmostly optimal solutions for benchmark models. Unlike someprevious works, our algorithm is not limited to assemble few

Abstracts

specific objects, but it can deal with diverse kind of objects. To
the best of our knowledge, this is the most extensive empirical
study on the problem.
RWA4
A Model with Evolutionary Covariance-based Learning forHigh-Frequency Financial Forecasting
Ricardo Araujo, Adriano Oliveira, Silvio MeiraSeveral approaches have been investigated to develop models
able to solve forecasting problems. However, a limitation arisesin the particular case of daily-frequency financial forecastingand is called the random walk dilemma (RWD). In this context, the concept of time phase adjustment can be included inforecasting models to overcome such a drawback. But the evolution of trading systems has increased the frequency for performing operations in the stock market for fractions of seconds,
which requires the analysis of high-frequency financial time series. Thus, this work proposes a model, called the increasing
decreasing linear neuron (IDLN), to forecast high-frequency financial time series from the Brazilian stock market. Furthermore, an evolutionary covariance-based method with automatictime phase adjustment is presented for the design of the proposed model, and the obtained results overcame those obtainedby classical forecasting models in the literature.
Diversity Guided Evolutionary Mining of Hierarchical Process Models
Thomas Molka, David Redlich, Marc Drobek, Xiao-Jun Zeng,
Wasif Gilani
Easy-to-understand and up-to-date models of business processes
are important for enterprises, as they aim to describe how work
is executed in reality and provide a starting point for process
analysis and optimization. With an increasing amount of event
data logged by information systems today, the automatic discovery of process models from process logs has become possible. Whereas most existing techniques focus on the discovery of well-formalized models (e.g. Petri nets) which are
popular among researchers, business analysts prefer businessdomain-specific models (such as Business Process Model Notation, BPMN) which are not well formally specified. We present
and evaluate an approach for discovering the latter type of process models by formally specifying a hierarchical view on business process models and applying an evolution strategy on it.
The evolution strategy efficiently finds process models which
best represent a given event log by using fast methods for process model conformance checking, and is partly guided by thediversity of the process model population. The approach contributes to the field of evolutionary algorithms by showing thatthey can be successfully applied in the real-world use case ofprocess discovery, and contributes to the process discovery domain by providing a promising alternative to existing methods.

Abstracts

A Biased Random-key Genetic Algorithm for Placement of
Virtual Machines across Geo-Separated Data Centers
Fernando Stefanello, Vaneet Aggarwal, Luciana Buriol, José
Gonçalves, Mauricio Resende
Cloud computing has recently emerged as a new technology for
hosting and supplying services over the Internet. This technology has brought many benefits, such as eliminating the need formaintaining expensive computing hardware and allowing business owners to start from small and increase resources only when
there is a rise in service demand. With an increasing demand forcloud computing, providing performance guarantees for applications that run over cloud become important. Applications canbe abstracted into a set of virtual machines with certain guarantees depicting the quality of service of the application. In
this paper, we consider the placement of these virtual machines
across multiple data centers, meeting the quality of service requirements while minimizing the bandwidth cost of the data
centers. This problem is a generalization of the NP-hard Generalized Quadratic Assignment Problem (GQAP). We formalize
the problem and propose a novel algorithm based on a biased
random-key genetic algorithm (BRKGA) to find near-optimal
solutions for the problem. The experimental results show thatthe proposed algorithm is effective in quickly finding feasible
solutions and it produces better results than a baseline aproachprovided by a commercial solver and a multi-start algorithm.
A Genetic Programming Approach to Cost-Sensitive Control
in Resource Constrained Sensor Systems
Afsoon Yousefi Zowj, Josh Bongard, Christian Skalka
Resource constrained sensor systems are an increasingly attractive option in a variety of environmental monitoring domains,due to continued improvements in sensor technology. However, sensors for the same measurement application can differ interms of cost and accuracy, while fluctuations in environmental
conditions can impact both application requirements and available energy. This raises the problem of automatically controllingheterogeneous sensor suites in resource constrained sensor system applications, in a manner that balances cost and accuracy ofavailable sensors. We present a method that employs a hierar-

123

chy of model ensembles trained by genetic programming (GP):if model ensembles that poll low-cost sensors exhibit too muchprediction uncertainty, they automatically transfer the burden ofprediction to other GP-trained model ensembles that poll more
expensive and accurate sensors. We show that, for increasingly
challenging datasets, this hierarchical approach makes predictions with equivalent accuracy yet lower cost than a similar yet
non-hierarchical method in which a single GP-generated model
determines which sensors to poll at any given time. Our results
thus show that a hierarchy of GP-trained ensembles can serve asa control algorithm for heterogeneous sensor suites in resource
constrained sensor system applications that balances cost andaccuracy.
RWA5
Evolutionary Learning of Syntax Patterns for Genic Interaction Extraction
Alberto Bartoli, Andrea De Lorenzo, Eric Medvet, Fabiano Tarlao, Marco Virgolin
There is an increasing interest in the development of techniques
for automatic relation extraction from unstructured text. The
biomedical domain, in particular, is a sector that may greatly
benefit from those techniques due to the huge and ever increasing amount of scientific publications describing observed phenomena of potential clinical interest. In this paper, we consider
the problem of automatically identifying sentences that containinteractions between genes and proteins, based solely on a dictionary of genes and proteins and a small set of sample sentencesin natural language. We propose an evolutionary technique forlearning a classifier that is capable of detecting the desired sentences within scientific publications with high accuracy. The
key feature of our proposal, that is internally based on Genetic
Programming, is the construction of a model of the relevant syntax patterns in terms of standard part-of-speech annotations. The
model consists of a set of regular expressions that are learned automatically despite the large alphabet size involved. We assess
our approach on two realistic datasets and obtain 74% accuracy,
a value sufficiently high to be of practical interest and that is inline with significant baseline methods.

Search-Based Software Engineering and Self-* Search
SBSE-SS1
Optimal Parameter Choices Through Self-Adjustment: Applying the 1/5-th Rule in Discrete Settings
Benjamin Doerr, Carola Doerr
While evolutionary algorithms are known to be very successful for a broad range of applications, the algorithm designer isoften left with many algorithmic choices, for example, the sizeof the population, the mutation rates, and the crossover rates of
the algorithm. These parameters are known to have a crucial
influence on the optimization time, and thus need to be chosencarefully, a task that often requires substantial efforts. Moreover,
the optimal parameters can change during the optimization process. It is therefore of great interest to design mechanisms thatdynamically choose best-possible parameters. An example forsuch an update mechanism is the one-fifth success rule for stepsize adaption in evolutionary strategies. While in continuous domains this principle is well understood also from a mathematicalpoint of view, no comparable theory is available for problems
in discrete domains. In this work we show that the one-fifth
success rule can be effective also in discrete settings. We regard the (1 + (λ, λ)) GA proposed in [Doerr/Doerr/Ebel: From124

black-box complexity to designing new genetic algorithms, TCS
2015]. We prove that if its population size is chosen according tothe one-fifth success rule then the expected optimization time on
O NE M AX is linear. This is better than what any static population size λ can achieve and is asymptotically optimal also among
all adaptive parameter choices.
Random or Genetic Algorithm Search for Object-Oriented
Test Suite Generation?
Sina Shamshiri, José Miguel Rojas, Gordon Fraser, Phil
McMinnAchieving high structural coverage is an important aim in software testing. Several search-based techniques have proved successful at automatically generating tests that achieve high coverage. However, despite the well- established arguments behindusing evolutionary search algorithms (e.g., genetic algorithms)
in preference to random search, it remains an open question
whether the benefits can actually be observed in practice whengenerating unit test suites for object-oriented classes. In this paper, we report an empirical study on the effects of using a genetic algorithm (GA) to generate test suites over generating test
suites incrementally with random search, by applying the EvoSuite unit test suite generator to 1,000 classes randomly selectedfrom the SF110 corpus of open source projects. Surprisingly, theresults show little difference between the coverage achieved bytest suites generated with evolutionary search compared to thosegenerated using random search. A detailed analysis reveals thatthe genetic algorithm covers more branches of the type where
standard fitness functions provide guidance. In practice, however, we observed that the vast majority of branches in the analyzed projects provide no such guidance.

Abstracts

SBSE-SS2
Learning Feature-Parameter Mappings for Parameter Tuning via the Profile Expected Improvement
Jakob Bossek, Bernd Bischl, Tobias Wagner, Günter Rudolph
The majority of algorithms can be controlled or adjusted by parameters. Their values can substantially affect the algorithms’
performance. Since the manual exploration of the parameter
space is tedious – even for few parameters – several automatic
procedures for parameter tuning have been proposed. Recent
approaches also take into account some characteristic properties of the problem instances, frequently termed instance features. These approaches, however, rely on a subdivision of theinstances into discrete clusters. Our contribution is the proposalof a novel concept for feature-based algorithm parameter tuning,which applies an approximating surrogate model for learning thecontinuous feature-parameter mapping. To accomplish this, welearn a joint model of the algorithm performance based on boththe algorithm parameters and the instance features. The required
data is gathered using a recently proposed acquisition function
for model refinement in surrogate-based optimization: the profile expected improvement. This function provides an avenue for
maximizing the information required for the feature-parameter
mapping, i.e., the mapping from instance features to the corresponding optimal algorithm parameters. The approach is validated by applying the tuner to exemplary evolutionary algorithms and problems, for which theoretically grounded or heuristically determined feature-parameter mappings are available.
Operator Selection using Improved Dynamic Multi-Armed
BanditJany Belluz, Marco Gaudesi, Giovanni Squillero, Alberto Tonda

Extracting Variability-Safe Feature Models from Source
Code Dependencies in System Variants
Wesley Assunção, Roberto Lopez-Herrejon, Lukas Linsbauer,
Silvia Vergilio, Alexander Egyed
To effectively cope with increasing customization demands,
companies that have developed variants of software systems are
faced with the challenge of consolidating all the variants into a
Software Product Line, a proven development paradigm capableof handling such demands. A crucial step in this challenge is toreverse engineer feature models that capture all the required feature combinations of each system variant. Current research has
explored this task using propositional logic, natural language,
and search-based techniques. However, using knowledge fromthe implementation artifacts for the reverse engineering task has
not been studied. We propose a multi-objective approach that
not only uses standard precision and recall metrics for the combinations of features but that also considers variability-safety,
i.e. the property that, based on structural dependencies among
elements of implementation artifacts, asserts whether all feature
combinations of a feature model are in fact well-formed software systems. We evaluate our approach with five case studies
and highlight its benefits for the software engineer.

Evolutionary algorithms greatly benefit from an optimal application of the different genetic operators during the optimization
process: thus, it is not surprising that several research lines in literature deal with the self-adapting of activation probabilities for
operators. The current state of the art revolves around the useof the Multi-Armed Bandit (MAB) and Dynamic Multi-Armedbandit (D-MAB) paradigms, that modify the selection mechanism based on the rewards of the different operators. Suchmethodologies, however, update the probabilities after each operator’s application, creating possible issues with positive feedbacks and impairing parallel evaluations, one of the strongest
advantages of evolutionary computation in an industrial perspective. Moreover, D-MAB techniques often rely upon measurements of population diversity, that might not be applicable to all
real-world scenarios. In this paper, we propose a generalizationof the D-MAB approach, paired with a simple mechanism for
operator management, that aims at removing several limitationsof other D-MAB strategies, allowing for parallel evaluations andself-adaptive parameter tuning. Experimental results show thatthe approach is particularly effective with frameworks containing many different operators, even when some of them are illsuited for the problem at hand, or are sporadically failing, as it
commonly happens in the real world.

Abstracts

Reducing Energy Consumption Using Genetic Improvement
Bobby Bruce, Justyna Petke, Mark Harman
Genetic Improvement (GI) is an area of Search Based Software
Engineering which seeks to improve software’s non-functional
properties by treating program code as if it were genetic material
which is then evolved to produce more optimal solutions. Hitherto, the majority of focus has been on optimising program’s
execution time which, though important, is only one of many
non-functional targets. The growth in mobile computing, cloudcomputing infrastructure, and ecological concerns are forcing
developers to focus on the energy their software consumes. We
report on investigations into using GI to automatically find moreenergy efficient versions of the MiniSAT Boolean satisfiability
solver when specialising for three downstream applications. Our
results find that GI can successfully be used to reduce energy
consumption by up to 25%
Web Service Antipatterns Detection Using Genetic Programming
Ali Ouni, Raula Gaikovina Kula, Marouane Kessentini, Katsuro
Inoue
Service-Oriented Architecture (SOA) is an emerging paradigm
that has radically changed the way software applications are architected, designed and implemented. SOA allows developers
to structure their systems as a set of ready-made, reusable andcompostable services. The leading technology used today for
implementing SOA is Web Services. Indeed, like all software,
Web services are prone to change constantly to add new user requirements or to adapt to environment changes. Poorly plannedchanges may risk introducing antipatterns into the system. Consequently, this may ultimately leads to a degradation of software
quality, evident by poor quality of service (QoS). In this paper,
we introduce an automated approach to detect Web service antipatterns using genetic programming. Our approach consists ofusing knowledge from real-world examples of Web service antipatterns to generate detection rules based on combinations of
metrics and threshold values. We evaluate our approach on abenchmark of 310 Web services and a variety of five types of
Web service antipatterns. The statistical analysis of the obtained
results provides evidence that our approach is efficient to detect
most of the existing antipatterns with a score of 85% of precisionand 87% of recall.
SBSE-SS3
Heuristic Model Checking using a Monte-Carlo Tree Search
Algorithm
Simon Poulding, Robert Feldt
Monte-Carlo Tree Search algorithms have proven extremely effective at playing games that were once thought to be difficultfor AI techniques owing to the very large number of possible
game states. The key feature of these algorithms is that rather
than exhaustively searching game states, the algorithm navigates
the tree using information returned from a relatively small num-125

ber of random game simulations. A practical limitation of software model checking is the very large number of states that amodel can take. Motivated by an analogy between exploring
game states and checking model states, we propose that MonteCarlo Tree Search algorithms might also be applied in this domain to efficiently navigate the model state space with the objective of finding counterexamples which correspond to potential software faults. We describe such an approach based on
Nested Monte-Carlo Search—a tree search algorithm applicableto single player games—and compare its efficiency to traditional
heuristic search algorithms when using Java PathFinder to locate
deadlocks in 12 Java programs.
SPRINT Multi-Objective Model Racing
Tiantian Zhang, Michael Georgiopoulos, Georgios Anagnostopoulos
Multi-objective model selection, which is an important aspectof Machine Learning, refers to the problem of identifying a setof Pareto optimal models from a given ensemble of models.
This paper proposes SPRINT-Race, a multi-objective racing algorithm based on the Sequential Probability Ratio Test with an
Indifference Zone. In SPRINT-Race, a non-parametric ternarydecision sequential analogue of the sign test is adopted to identify pair-wise dominance and non-dominance relationship. In
addition, a Bonferroni approach is employed to control the overall probability of any erroneous decisions. In the fixed confidence setting, SPRINT-Race tries to minimize the computational
effort needed to achieve a predefined confidence about the quality of the returned models. The efficiency of SPRINT-Race isanalyzed on artificially-constructed multi-objective model selection problems with known ground-truth. Moreover, SPRINTRace is applied to identifying the Pareto optimal parameter settings of Ant Colony Optimization algorithms in the context ofsolving Traveling Salesman Problems. The experimental results
confirm the advantages of SPRINT-Race for multi-objectivemodel selection.
Deep Parameter Optimisation
Fan Wu, Westley Weimer, Mark Harman, Yue Jia, Jens Krinke
We introduce a mutation-based approach to automatically discover and expose ‘deep’ (previously unavailable) parametersthat affect a program’s runtime costs. These discovered parameters, together with existing (‘shallow’) parameters, form asearch space that we tune using search-based optimisation in abi-objective formulation that optimises both time and memory
consumption. We implemented our approach and evaluated it on
four real-world programs. The results show that we can improve
execution time by 12% or achieve a 21% memory consumption
reduction in the best cases. In three subjects, our deep parametertuning results in a significant improvement over the baseline ofshallow parameter tuning, demonstrating the potential value ofour deep parameter extraction approach.

126

A Hyper-Heuristic for the Multi-Objective Integration andTest Order Problem
Giovani Guizzo, Gian Fritsche, Silvia Vergilio, Aurora Pozo
Multi-objective evolutionary algorithms (MOEAs) have been efficiently applied to Search-Based Software Engineering (SBSE)
problems. However, skilled software engineers waste significant effort designing such algorithms for a particular problem,
adapting them, selecting operators and configuring parameters.
Hyper-heuristics can help in these tasks by dynamically selecting or creating heuristics. Despite of such advantages, we observe a lack of works regarding this subject in the SBSE field.

Abstracts

Considering this fact, this work introduces HITO, a Hyperheuristic for the Integration and Test Order Problem. It includes
a set of well-defined steps and is based on two selection functions (Choice Function and Multi-armed Bandit) to select thebest low-level heuristic (combination of mutation and crossover
operators) in each mating. To perform the selection, a quality measure is proposed to assess the performance of low-level
heuristics throughout the evolutionary process. HITO was implemented using NSGA-II and evaluated to solve the integration and test order problem in seven systems. The introduced
hyper-heuristic obtained the best results for all systems, whencompared to a traditional algorithm.

TheoryTHEORY1
Improved Runtime Bounds for the (1+1) EA on Random 3CNF Formulas Based on Fitness-Distance Correlation
Benjamin Doerr, Frank Neumann, Andrew SuttonWith this paper, we contribute to the theoretical understanding ofrandomized search heuristics by investigating their behavior on
random 3-SAT instances. We improve the results for the (1+1)
EA obtained by Sutton and Neumann [PPSN 2014, 942–951] inthree ways. First, we reduce the upper bound by a linear factor
and prove that the (1+1) EA obtains optimal solutions in timeO(n log n) with high probability on asymptotically almost all
high-density satisfiable 3-CNF formulas. Second, we extend therange of densities for which this bound holds to satisfiable formulas of at least logarithmic density. Finally, we complement
these mathematical results with numerical experiments that summarize the behavior of the (1+1) EA on formulas along the density spectrum, and suggest that the implicit constants hidden in
our bounds are low. Our proofs are based on analyzing the run of
the algorithm by establishing a fitness-distance correlation. Thisapproach might be of independent interest and we are optimisticthat it is useful for the analysis of randomized search heuristics
in various other settings. To our knowledge, this is the first timethat fitness-distance correlation is explicitly used to rigorously
prove a performance statement for an evolutionary algorithm.

is much longer than the time it takes for a new beneficial mutation to take over the population. In this situation, the population
only contains copies of one genotype and evolution can be modelled as a (1+1)-type process where the probability of accepting a new genotype (improvements or worsenings) depends onthe change in fitness. We present an initial runtime analysis of
SSWM, quantifying its performance for various parameters andinvestigating differences to the (1+1)EA. We show that SSWM
can have a moderate advantage over the (1+1)EA at crossing fitness valleys and study an example where SSWM outperforms
the (1+1)EA by taking advantage of information on the fitness
gradient.
Population Size vs. Mutation Strength for the (1+λ) EA on
OneMaxChristian Giessen, Carsten WittFirst Steps Towards a Runtime Comparison of Natural andArtificial Evolution

The (1+1) EA with mutation probability c/n, where c > 0
is an arbitrary constant, is studied for the classical O NE M AX
function. Its expected optimization time is analyzed exactly(up to lower order terms) as a function of c and λ. It turns
out that 1/n is the only optimal mutation probability if λ =o(ln n ln ln n/ln ln ln n), which is the cut-off point for linear
speed-up. However, if λ is above this cut-off point then thestandard mutation probability 1/n is no longer the only optimal choice. Instead, the expected number of generations is (upto lower order terms) independent of c, irrespectively of it being
less than 1 or greater. The results are obtained by a careful studyof order statistics of the binomial distribution and variable drift
theorems for upper and lower bounds.

Tiago Paixao, Jorge Perez Heredia, Dirk Sudholt, Barbora
Trubenova

Populations can be Essential in Dynamic Optimisation

THEORY2

Evolutionary algorithms (EAs) form a popular optimisation
paradigm inspired by natural evolution. In recent years the fieldof evolutionary computation has developed a rigorous analyticaltheory to analyse their runtime on many illustrative problems.
Here we apply this theory to a simple model of natural evolution. In the Strong Selection Weak Mutation (SSWM) evolutionary regime the time between occurrence of new mutations

Duc-Cuong Dang, Thomas Jansen, Per Kristian Lehre
Real-world optimisation problems are often dynamic. Previously good solutions must be updated or replaced due to changes
in objectives and constraints. It is often claimed that evolutionary algorithms are particularly suitable for dynamic optimisation because a large population can contain different solutions
that may be useful in the future. However, rigorous, theoreti-

Abstracts

cal demonstrations for how populations in dynamic optimisation
can be essential are sparse and restricted to special cases. This
paper provides theoretical explanations of how populations canbe essential in evolutionary dynamic optimisation. The abilityof evolutionary algorithms to track optimal solutions is investigated by considering a Hamming ball of optimal points thatmoves randomly through the search space. It is shown that algorithms based on a single individual are likely to be unable
to track the optimum while non-elitist population-based evolutionary algorithms can be able to do so with overwhelmingly
high probability. It is shown that this holds for a range of themost commonly used selection mechanisms even without diversity enhancing mechanisms. Appropriate parameter settings toachieve this behaviour are derived for these selection mechanisms.
THEORY3
On the Utility of Island Models in Dynamic Optimization
Andrei Lissovoi, Carsten Witt
A simple island model with λ islands and migration occurring
after every τ iterations is studied on the dynamic fitness function Maze. This model is equivalent to a (1+λ) EA if τ = 1, i.e.,
migration occurs during every iteration. It is proved that evenfor an increased offspring population size up to λ = O(n1− ),the (1+λ) EA is still not able to track the optimum of Maze. If
the migration interval is increased, the algorithm is able to trackthe optimum even for logarithmic λ. Finally, the relationship of
τ , λ, and the ability of the island model to track the optimum isinvestigated more closely.
THEORY4
An Evolutionary Game Theoretic Analysis of Difference
Evaluation Functions
Mitchell Colby, Kagan Tumer
One of the key difficulties in cooperative coevolutionary algorithms is solving the credit assignment problem. Given the performance of a team of agents, it is difficult to determine the effectiveness of each agent in the system. One solution to solving the credit assignment problem is the difference evaluation
function, which has produced excellent results in many multiagent coordination domains, and exhibits the desirable theoretical properties of alignment and sensitivity. However, to date,there has been no prescriptive theoretical analysis deriving conditions under which difference evaluations improve the probability of selecting optimal actions. In this paper, we derive suchconditions. Further, we prove that difference evaluations do notalter the Nash equilibria locations or the relative ordering of fitness values for each action, meaning that difference evaluations
do not typically harm converged system performance in cases
where the conditions are not met. We then demonstrate the theoretical findings using an empirical basins of attraction analysis.

127

On Easiest Functions for Somatic Contiguous Hypermutations And Standard Bit Mutations
Dogan Corus, Jun He, Thomas Jansen, Pietro Oliveto, Dirk Sudholt, Christine Zarges
Understanding which function classes are easy and which are
hard for a given algorithm is a fundamental question for the analysis and design of bio-inspired search heuristics. A natural starting point is to consider the easiest and hardest functions for analgorithm. For the (1+1)EA using standard bit mutation it is wellknown that OneMax is an easiest function with unique optimum
while Trap is a hardest. In this paper we extend the analysis ofeasiest function classes to the contiguous somatic hypermutation(CHM) operator used in artificial immune systems. We define afunction MinBlocks and prove that it is an easiest function forthe (1+1)EA using CHM, presenting both a runtime and a fixedbudget analysis. Since MinBlocks is, up to a factor of 2, a hardest function for standard bit mutations, we consider the effectsof combining both operators into a hybrid algorithm. We showthat an easiest function for the hybrid algorithm is not just a
trivial weighted combination of the respective easiest functions
for each operator. Nevertheless, by combining the advantagesof both operators, the hybrid algorithm has optimal asymptotic
performance on both OneMax and MinBlocks.
A Tight Runtime Analysis of the (1 + (λ, λ)) Genetic Algorithm on OneMax
Benjamin Doerr, Carola Doerr
Understanding how crossover works is still one of the big challenges in evolutionary computation research, and making ourunderstanding precise and proven by mathematical means might
be an even bigger one. As one of few examples where crossoverprovably is useful, the (1 + (λ, λ)) Genetic Algorithm (GA)was proposed recently in [Doerr, Doerr, Ebel. Lessons From
the Black-Box: Fast Crossover-Based Genetic Algorithms. TCS
2015]. Using the fitness level method, the expected optimization time on general O NE M AX functions was analyzed and aO(max{n log(n)/λ, λn}) bound was proven for any offspring
population size λ ∈ [1..n]. We improve this work in several
ways, leading to sharper bounds and a better understanding of
how the use of crossover speeds up the runtime in this algorithm. We first improve the upper bound on the runtime toO(max{n log(n)/λ, nλ log log(λ)/ log(λ)}). This improvement is made possible from observing that in the parallel generation of λ offspring via crossover (but not mutation), the bestof these often is better than the expected value, and hence several fitness levels can be gained in one iteration. We thenpresent the first lower bound for this problem. It matches ourupper bound for all values of λ. This allows to determine
the asymptotically
optimal value for the population size. It isp
λ = Θ( log(n) log log(n)/p log log log(n)), which gives anoptimization time of Θ(n log(n) log log log(n)/ log log(n)).
Hence the improved runtime analysis both gives a runtime guar-

128

antee improved by a super-constant factor and yields a better
actual runtime (faster by more than a constant factor) by suggesting a better value for the parameter λ. We finally give a tailbound for the upper tail of the runtime distribution, which showsthat the actual runtime exceeds our runtime guarantee by a factorof (1 + δ) with probability O((n/λ2 )−δ ) only.
OneMax in Black-Box Models with Several Restrictions
Carola Doerr, Johannes Lengler
As in classical runtime analysis the O NE M AX problem is themost prominent test problem also in black-box complexity theory. It is known that the unrestricted, the memory-restricted,
and the ranking-based black-box complexities of this problem
are all of order n/ log n, where n denotes the length of the bit
strings. The combined memory-restricted ranking-based black-

Abstracts

box complexity of O NE M AX, however, was not known. We
show in this work that it is Θ(n) for the smallest possible size
bound, that is, for (1+1) black-box algorithms. We extend thisresult by showing that even if elitist selection is enforced, there
exists a linear time algorithm optimizing O NE M AX with failure probability o(1). This is quite surprising given that all previously regarded algorithms with o(n log n) runtime on O NE M AX, in particular the quite natural (1 + (λ, λ)) GA, heavily
exploit information encoded in search points of fitness muchsmaller than the current best-so-far solution. Also for othersettings of µ and λ we show that the (µ + λ) elitist memoryrestricted ranking-based black-box complexity of O NE M AX isas small as (an advanced version of) the information-theoretic
lower bound. Our result enlivens the quest for natural evolutionary algorithms optimizing O NE M AX in o(n log n) iterations.

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131

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