bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulation
Authors: McLeod John
Published: January 2007

Simulation can be a more effective tool for the study of problems of our times if the practitioners will adopt procedures which will make simulation more a science than an art. A big step in that direction would be the development and use of a standard format that would assure adequate and uniform documentation. Such a format is proposed, and criticism is solicited.
What hath got Roth
Authors: Roth Paul F.
Published: January 2007

This column wishes to acknowledge the reassignment of Andy Hesser, who has been active and productive in computer systems simulation for quite a while. Not only that, but also quite communicative and a very witty presenter.
Tools and techniques for improving the efficiency of federal automatic data processing operations
Authors: Highland Harold Joseph
Published: January 2007

Because of numerous members interested in the simulation of computer systems, I have included this note about a new volume issued by the GAO (General Accounting Office). This 44-page document was prepared last winter and resulted in the formation of a CPE office within the GSA (General Services Administration).
Sensitivity of predictive scheduling
Authors: Leung Ka-Lai , Wood Roger C. , Chiu Willy Wai-Yee
Published: January 2007

A popular CPU (Central Processing Unit) scheduling strategy is to give high priority to those jobs with short CPU service times. There are several algorithms for predicting which jobs among all the resident jobs have short service times. No scheme, however, has proved to be 100% accurate in identifying the short jobs. This paper, utilizing results from both simulation and mathematical models, studies the sensitivity of CPU utilization to the accuracy of the predictive algorithm.
Simulation documents available from NTIS
Authors: Ören Tuncer I.
Published: January 2007

What is NTIS:
The NTIS (National Technical Information Service) of the U.S. Department of Commerce is a central source for the public sale of (i) Government-sponsored research and development reports, (ii) Government analyses prepared by Federal agencies, their contractors or grantees, (iii) Federally sponsored translations, and (iv) some reports written in foreign languages. The NTIS reports exist in paper copy (PC) or in micro-riche (MF) and are available indefinitely. NTIS ships about 12000 documents daily.
A new discrete quantitative randomized response model
Authors: Liu P. T. , Chow L. P.
Published: January 2007

The Randomized Response Technique, which was originally developed for qualitative purposes, is being developed for quantitative purposes, and the current article presents a new discrete quantitative RRT model. This model uses a predetermined combination of balls in the randomizing device, instead of asking an innocuous question. It has been shown that the procedures of administering the model is simple and that its efficiency of estimate is higher than the other currently available models.
Modular program in basic
Authors: Highland Harold Joseph
Published: January 2007

The 'Barbershop Problem' is primodial and ubiquitous in the teaching of modeling and simulation. It was only natural to present it to a class in "Conceptual Modeling, " which I taught about a year ago in the Computer Science Department of Hofstra University [Hempstead, Long Island, New York].
Simulation of resource allocation alternatives for hospital facilities
Authors: Johnson G. Miles , Kho James W.
Published: January 2007

Methodologies for developing a comprehensive hospital input/output model are summarized. Specifically covered are:• The development of a hospital data base that allows simulation of various resource allocation configurations.• The application of user-oriented modeling techniques for simulating hospital facilities.• A case study of simulating patient flow through a radiology facility is presented in terms of model development and utilization of simulation output.
A network modeling and analysis technique for the evaluation of nuclear safeguards systems effectiveness
Authors: Grant Floyd H. , Miner Robin J. , Engi Dennis
Published: January 2007

Nuclear safeguards systems are concerned with the physical protection and control of nuclear materials. The Safeguards Network Analysis Procedure (SNAP) provides a convenient and standard analysis methodology for the evaluation of safeguards system effectiveness. This is achieved through a standard set of symbols which characterize the various elements of safeguards systems and an analysis program to execute simulation models built using the SNAP symbology. The reports provided by the SNAP simulation program enable analysts to evaluate existing sites as well as alternative design possibilities. This paper describes the SNAP modeling technique and provides an example illustrating its use.
A Production Analysis Simulation System (PASS)
Authors: Blumberg Donald F.
Published: January 2007

The Production Analysis Simulation System, PASS, is a computer-based simulation system designed to represent the key elements of electronics, electro-mechanical or mechanical assembly oriented manufacturing operations. PASS provides management with a precise mechanism:• To evaluate the efficiency and/or capacity of these operations• To generate estimates of the impact of a wide variety of strategic and tactical changes in the production systemThe PASS simulation produces a set of detailed measurements of each alternative manufacturing strategy and tactic. These measurements enable the manufacturing manager to assess the trade-offs between these alternatives. The following standard measurements are generated by PASS:• Finished goods and work-in-process inventory levels• Manpower utilization and costs• Stockout levels including- a record of the percentage of late deliveries for each assembly, sub-assembly, accessory, etc.- for all late orders, a distribution describing the number of days late.• A detailed record of the manufacturing and manpower planning process is also represented.In summary, PASS is a simulation system that provides answers to "WHAT IF .... ?" questions about alternative manufacturing operating strategies such as changes in product flow, cycle times, production to order versus production to inventory, etc. These answers are produced in the form of detailed, quantitative reports which provide top management with a precise dollars and cents, hours and minutes report of the impact of each alternative manufacturing strategy and tactic under evaluation.
Additive vs multiplicative uniform pseudo-random number generators in the generation of Erlang variates
Authors: Burford Roger L.
Published: January 2007

This paper presents the comparative results of several test runs involving the use of several unit uniform random number generators with an inverse transform to generate Erland random variates with λ=1 and k = 3, 4, 5, and 6. The results show that two commonly used generators (a multiplicative and a mixed one) produce unacceptable results. Two others (an additive one and a multiplicative one) produce acceptable results. The computer system used is an IBM 370/3033.
Some speculation on simulation and information systems
Authors: Lucas Henry C.
Published: January 2007

An information systems as a set of procedures which process data used to support decision making. Robert Anthony (1965) has suggested a taxonomy of decision types which provides information useful in thinking about systems. Strategic planning decisions involve setting the objectives of the organization. Managerial control decisions deal with the task of determining that resources are employed to achieve the goals set in strategic planning. Operational control decisions deal with the day-to-day operations of the firm.
The use of simulation modeling in determining Defense manpower
Authors: Ebeling Charles E.
Published: January 2007

Accurate determinations of manpower requirements of a combat unit such as a tactical fighter wing or a carrier task force is a stated goal of the Department of Defense. Such determinations must be defensible to both the Executive Branch (Office of Management and Budget and the President) and Congress. In order to assess manpower requirements under various combat conditions, the three services have adopted computer simulation models. While Monte Carlo simulation has provided a means of estimating wartime manpower, it has also introduced several problems which must be overcome if simulation is to continue to play an important role in assessing Department of Defense requirements. These problems have centered on the need for extensive computer and personnel resources, the lack of responsiveness to changing scenarios, the collection of reliable and accurate data, and the increasing complexity and sophistication of the models.
Simple simulation
Authors: Wilson Richard C.
Published: January 2007

This paper describes an example of a network flow modelling approach for "quick and dirty" analysis of traffic dynamics in material handling systems. The example is based on a real installation. It serves to demonstrate potential for quickly comparing the design feasibility of alternate conveyor system layouts under dynamic loading before using specially programmed simulations.
Continuous simulation
Authors: Kwok Bosco Pak-cheung
Published: January 2007

This project provides a framework for continuous simulation in SIMULA. Most of the procedures in the CSSL (Continuous System Simulation Language) are made available in SIMULA to facilitate the continuous simulation. CSSL is a statement-oriented language used to simulate the dynamics of continuous systems describable by ordinary differential equations. It is hoped that further work on such project will make available the full capabilities of continuous simulation in SIMULA.
Patterns of modelling
Authors: Kreutzer Wolfgang
Published: January 2007

Success of any standardization effort is highly sensitive to user acceptance and satisfaction. Conceptual simplicity, congruence, power, transparency, flexibility and interpretative efficiency of modelling methodologies and their processor systems are at least partially conflicting goals between which suitable tradeoffs have to be made.Solutions to this problem will neither be found through excessive generality nor a proliferation of weakly related special purpose concepts, but by a reliable approach towards engineering of complex systems relative to a secure and powerfull conceptual basis.This paper argues in favour of spectra of high-level, user-oriented modelling interfaces built on top of a hierarchically extended base language. A brief outline of cognitive structures in problem solving and discrete event simulation serves to support the subsequent discussion of basic conceptual and notational abstractions and their mapping into implementation structures.Some final remarks on costs and benefits of instrumental congruences and the impact of technological developments on price/performance tradeoffs between information processing system components serve to underline the recommendations.
Small-sample behavior of Weighted Least Squares in experimental design applications
Authors: Kleijnen Jack , Brent Renée , Brouwers Rien
Published: January 2007

In experimental design applications unbiased estimators s
2
i
of the variances σ
2
i
are possible. These estimators may be used in Weighted Least Squares (WLS) when estimating the parameters β The resulting small-sample behavior is investigated in a Monte Carlo experiment. This experiment shows that an asymptotically valid covariance formula can be used if s
2
i
is based on, say, at least 5 observations. The WLS estimator based on estimators s
2
i
gives more accurate estimators of β, provided the σ
2
i
differ by a factor, say, 10.
Cost effectiveness of the simulation languages
Authors: Niedereichholz J.
Published: January 2007

Comparative GPSS 1100 and SIMULA I measurements using a simple job shop simulation.
Review of "Principles of Discrete Event Simulation, by George S. Fishman", John Wiley & Sons, 1978
Authors: Kleijnen Jack P. C.
Published: January 2007

This is George Fishman's second book on discrete simulation (his first book was published by Wiley in 1973). In a nutshell, this is an excellent book; it is a must for readers interested in the methodology of stochastic simulation; it is not ideal as a first introduction to simulation (for an introduction use, for example, T. H. Naylor et al., Computer simulation techniques, Wiley, 1966).
An improved event scanning mechanism for discrete state simulation
Authors: Wyman F. Paul
Published: January 2007

Simulation models of large, complex, "real world" applications have occasionally earned the reputation of eating up hours of computer time. This problem may be attributed in part to difficulties such as slow stochastic convergence. However, an additional problem lies in the fact that a significant amount of bookkeeping time is required to keep future events in their proper sequence. This paper presents a method for significantly reducing the time spent scanning future events lists in discrete state simulations. Three models are presented, all of which improve in effectiveness as the events-list scan problem becomes more burdensome.
An implementation of a computer simulation system
Authors: Nutt Gary J.
Published: January 2007

The field of discrete simulation of computer systems has been the subject of much criticism, particularly with respect to the amount of time required to construct programming models from a system design. Reduction of this lead time is a step toward easing the task of simulating large, discrete systems. A class of models called evaluation nets has previously been defined and is alleged to be useful in reducing the amount of time required to build the simulation program from the system design [1, 2]. An implementation of those models now exists at the University of Colorado, and experimentation into their usefulness is underway. Detailed documentation of the work is available [3].
Parking systems analysis
Authors: Ellis Raymond H. , Bennett John C. , Rassam Paul R.
Published: January 2007

The availability and quality of parking plays an important role in shaping the overall service provided by the highway system. The usefulness of the automobile can be impaired if the driver is unable to find convenient and reasonably priced parking in the vicinity of his final destination. Further, the design of the parking system can significantly influence the quality of the environment, particularly the ambient air quality and noise levels in high-density areas such as the central business district (CBD). Similarly, the choice of mode of access to transit, the selection of a transit station, and the difficulty of driving and parking in the CBD are critical inputs to modal choice and transit network evaluation models. In this context, the parking system constitutes an important element of the urban transportation system.
Randomness is a simulator's syndrome
Authors: Highland Harold Joseph
Published: January 2007

Back in mid-1973 I should have known enough to understand and follow Einstein's most basic principle, namely: &Omega = ε + ω + φ
A rejoinder to "Randomness is Nonsense"
Authors: Nance Richard E.
Published: January 2007

The brief note "Randomness Is Nonsense" offers an opinion of the concept of randomness that is inaccurate and confusing. This brief rejoinder attempts to clarify the arguments that lead to the conceptual problems involving "randomness", especially as the term is used in the context of random number generation.
Simulation of a dynamic balance theory
Authors: VAN KONINGSVELD BERRY
Published: January 2007

The purpose of this article is to report on an attempt to substitute a dynamic model for Heider's well known Psychological "Balance" theory.Additionally, a computer simulation of this model is suggested, with help of a computer language for dynamically modelling large samples of biological cells: CELLSIM. (Computer outputs are available upon request from Henk Koppelaar MPS group, Oudennoord 6, Utrecht.
Computer simulation
Authors: Upton Elizabeth M. , Sheth Anil
Published: January 2007

A computerized hotel simulation was developed for use by a senior class of undergraduates in a hospitality management program. The simulation is an integral part of a course entitled Computer Applications in Hotels and Restaurants. The objectives of the hotel simulation, in addition to illustrating the dynamics of hotel operation and procedural control, were to provide managerial experience in accounting, problem-solving and decision-making. Sub-systems relating to front office procedures and back office accounting are currently available in the model. Interactive terminal operation, shared file concepts and APL PLUS on a time-sharing basis are employed. The simulation has been used as a teaching tool in variety of ways as the size of the class has increased from 26 to 68 during the four years of simulation development. The actual computing cost per student of approximately $30.00, is low considering that the experience gained by using the simulation cannot be duplicated in any other way. Evaluation both by faculty and students has shown that the simulation did allow the application of theory and background knowledge to a model which closely resembled a real life situation. As a result the students were encouraged to solve problems and make decisions in a way that permitted a better understanding of the role of management in the real world. The type of education gained in such a computer applications course will develop user-managers who have the expertise to participate effectively in the development and use of management information systems. The simulation could also be used in special research projects; the concepts of the back office module could have wide application in other areas of business management.
Statistical tests of random number generators
Authors: Bohrer Robert , Putnam Daniel
Published: January 2007

This paper notes several results from statistical distribution theory which are useful in checking random number generators. It illustrates these methods by application to the normal random number generator GGNRF from the IMSL program package. Independence is checked with both time and frequency domain tests. The normal distributional properties are checked with goodness of fit tests and tests of the mean and variance.
Quantile estimation in regenerative simulation
Authors: Coppus G. W. J. , van Dongen M. P. F. M. , Kleinjen J. P. C.
Published: January 2007

We model key-punching in a computer center as a queuing simulation with 2 servers (typists) and 3 priority classes (small, medium, large jobs). The 90% quantile of queuing time is estimated for different borderlines between the 3 job classes. Confidence intervals for the quantiles are based on the regenerative properties of the simulation, as derived by Iglehart (1974). They utilize the asymptotic normality of the estimated quantile, and a rather complicated expression for its variance. Numerical results are given for the quantiles (and averages) of the queuing times in each job class, for several borderlines between the 3 job classes. The effects of simulation runlength on the confidence intervals were also examined. The effects of varying job-class borderlines were tentatively modeled by a regression model.
A nomogram for radiologic diagnosis of renal mass from excretory urogram information
Authors: Know Ali , Monorara Shojtisu , Fud Joe X.
Published: January 2007

The finding of a mass on excretory urogram entails a diagnostic dilemma. Four major possibilities are presented (listed here in decreasing order of importance):• Renal neoplasm, such as hypernephroma• Renal cysts present as multilocular structure or as a localized appearance of atypical polycystic kidneys, or presenting as a simple single serous cyst.• Nasal detrious, deriving from either a technician or radiologist suffering acute nasopharyngitis who sneezed on the film as it was being developed or put on the viewing panel. Sometimes these are produced by placing the fifth finger up the nares (Rosannadanna, 1978).• Renunculus, cortical nodule, or normally lumpy renal cortex.
Analysis of network congestion inference techniques
Authors: Chandramouli Y. , Neidhardt Arnold
Published: January 2007

Consider a neutral observer monitoring network performance based on external network measurements. Whenever congestion symptoms are observed within the network, the neutral observer would be interested in diagnosing the cause of the symptom, and in particular, identifying the congested link within the network. The neutral observer may contemplate to collect external network measurements reflective of network performance and from those measurements infer link delays to identify the congested link.Given the measurements collected, the following result has been obtained in this article. We prove that it is not possible to determine one-way link delays based on external network delay measurements. It is important to note that it is possible to determine one-way link delays with more information such as historical data or additional assumptions about directional delays.
Traffic matrix tracking using Kalman filters
Authors: Soule Augustin , Salamatian Kavé , Nucci Antonio , Taft Nina
Published: January 2007

In this work we develop a new approach to monitoring origin-destination flows in a large network. We start by building a state space model for OD flows that is rich enough to fully capture temporal and spatial correlations. We apply a Kalman filter to our linear dynamic system that can be used for both estimation and prediction of traffic matrices. We call our system a traffic matrix tracker due to its lightweight mechanism for temporal updates that enables tracking traffic matrix dynamics at small time scales. Our Kalman filter approach allows us to go beyond traffic matrix estimation in that our single system can also carry out traffic prediction and yield confidence bounds on the estimates, the predictions and the residual error processes. We show that these elements provide key functionalities needed by monitoring systems of the future for carrying out anomaly detection. Using real data collected from a Tier-1 ISP, we validate our model, illustrate that it can achieve low errors, and that our method is adaptive on both short and long timescales.
Peer review and the planning process
Authors: Robinson Robert J.
Published: January 2007

ACM's Special Interest Group on University Computer Centers (SIGUCC) has instituted a program to foster peer reviews among computing centers. That program is conceived as giving external advice and guidance to computer center directors, and is an appropriate mechanism for certain classes of need. However, at SUNY - Albany peer or external review is used in quite a different way--one integrally bound to the planning process. This paper describes our strategy and methodology in that context.
Report on the ACM International Workshop on Methodologies and Evaluation of Lexical Cohesion Techniques in Real-World Applications (ELECTRA 2005) held at SIGIR 2005
Authors: Vechtomova Olga , Jones Rosie , Dias Gaël
Published: January 2007

The workshop on Methodologies and Evaluation of Lexical Cohesion Techniques in Real-World Applications (ELECTRA 2005) was held in Salvador, Brazil on August 19 in conjunction with the 28
th
ACM Annual International Conference on Research and Development in Information Retrieval (SIGIR 2005). The aim of the workshop was to bring together researchers in NLP and IR to discuss the use of lexical cohesion in text applications, such as document and passage retrieval, question answering, topic segmentation and text summarization. There were a number of related workshops in the past: MEMURA 2004 Workshop on Methodologies and Evaluation of Multiword Units in Real-World Applications in association with the 4th International Conference on Language Resources (LREC 2004) [1], Multiword Expressions: Integrating Processing Workshop in association with the 42nd Annual Meeting of the Association for Computational Linguistics (ACL 2004) [2], and Multiword Expressions: Analysis, Acquisition and Treatment Workshop in association with the 41st Annual Meeting of the Association for Computational Linguistics (ACL 2003) [3]. The goal of this workshop was to address a wider range of lexical cohesion phenomena in text, not only multiword units, but also relations between words on the sentence, passage and document level, and how they can be useful for information retrieval applications.
Offsets from the perspective of computational algebraic geometry
Authors: Segundo F. San , Sendra J. R. , Sendra Juana
Published: January 2007

The offset hypersurface
O

d

(
V
), at distance
d
, to an irreducible hypersurface
V
is essentially the envelope of the system of spheres centered at the points of
V
with fixed radius
d
(for a formal definition, and for basic properties of offsets, see [2] and [9]). This type of geometric objects have been studied extensively by many authors in the frame of CAGD applications (see [4]). As a consequence of this research, many interesting theoretical and algorithmic questions related to algebraic and differential geometric properties of offsets have been addressed. In this context, one usually analyzes whether a certain property of the original variety
V
is translated to

O
d

(
V
) when offsetting.In this poster we present several efficient algorithms (and examples thereof) developed in our research group for the computation of algebraic and geometric properties of offset hypersurfaces.
Algebraic generalization
Authors: Watt Stephen M.
Published: January 2007

We explore the notion of generalization in the setting of symbolic mathematical computing. By "generalization" we mean the process of taking a number of instances of mathematical expressions and producing new expressions that may be specialized to all the instances. We identify a number of ways in which generalization may be useful in the setting of computer algebra. We formalize this generalization as an antiunification problem.The process of antiunification is the dual of unification. It takes two expressions
E
1
,
E
2
∈
E
(Σ,
V
) and produces
E
3
∈
E
(Σ,
V
) such that there exist substitutions σ
1
and σ
2
such that σ
1
(
E
3
) =
E
1
and σ
2
(
E
3
) =
E
2
. We call the pair of substitutions an
antiunifier
and the resulting expression a
generalization
of the expressions. An antiunifier always exists, but is not necessarily unique. There is, however, a unique
most specific antiunifier
that places the most restrictions on the variables. This gives the
most specific generalization
, which is unique up to renaming of variables.
New bounds for the Descartes method
Authors: Krandick Werner , Mehlhorn Kurt
Published: January 2007

We give a new bound for the number of recursive subdivisions in the Descartes method for polynomial real root isolation. Our proof uses Ostrowski's theory of normal power series from 1950 which has so far been overlooked in the literature. We combine Ostrowski's results with a theorem of Davenport from 1985 to obtain our bound. We also characterize normality of cubic polynomials by explicit conditions on their roots and derive a generalization of one of Ostrowski's theorems. The poster is based on a paper that is to appear in the Journal of Symbolic Computation [1]. In addition to the results of the paper the poster presents facsimiles of pertinent mathematical works in French, German, and English that span a period of 400 years. We use color-coding to relate the historical results to our theory.
An analytical model for computer system performance evaluation
Authors: Rice Don R.
Published: January 2007

This paper describes an analytical model of a computer system useful in the evaluation of system performance. The model is described in detail while the mathematics are minimized. Emphasis is placed on the utility of the model rather than the underlying theory and a number of illustrative examples are included.
What is formal verification?
Authors: Bjesse Per
Published: January 2007

Formal verification is the use of mathematical techniques to ensure that a design conforms to some precisely expressed notion of functional correctness. Concretely, assume that you have (1) a model of a design, (2) some description of the environment that the design is supposed to operate in, and (3) some properties that the design is intended to fulfill. Given this information, you may want to search for some input patterns that the environment could generate that will violate the properties. Classical approaches to demonstrating that such input stimuli exist are random simulation, or directed test. Formal verification is an alternative approach that can be used both to search for inputs sequences that violate the properties, and prove that the properties always hold in the case when no such stimuli exist.Formal verification can be applied to designs described at many different levels of abstraction, ranging from the gate level, to RTL implementations, and in some cases even to transaction level models described in standardized programming languages.There are several different use models for formal verification. Some design teams use it to boost the coverage of random simulation and hunt for bugs, whereas others make full blown use of it to conclusively prove that certain properties hold. State-of-the-art tools integrate formal verification engines with simulation in a seamless way.A particular formal verification problem of great interest in EDA is equivalence checking. Here, the property that is checked is whether two different designs always have the same input/output behavior with respect to some notion of equivalence. Special algorithms are used when it is known that the two designs differ only in restricted ways, for example when combinational optimization only has been used to derive one from the other.Compute resources required by formal verification algorithms generally grow very quickly as design sizes increase. Current formal verification research aims to increase the capacity of the design analysis algorithms, and to make formal verification usable earlier in the design cycle. For equivalence checking, hot topics include better capacity for data path verification and support for verification of sequential transformations.
Sampling algorithms for pure network topologies
Authors: Airoldi Edoardo M. , Carley Kathleen M.
Published: January 2007

In a time of information glut, observations about complex systems and phenomena of interest are available in several applications areas, such as biology and text. As a consequence, scientists have started searching for patterns that involve interactions among the objects of analysis, to the effect that research on models and algorithms for network analysis has become a central theme for knowledge discovery and data mining (KDD). The intuitions behind the plethora of approaches rely upon few basic types of networks, identified by specific local and global topological properties, which we term "pure" topology types.In this paper, (1) we survey pure topology types along with existing sampling algorithms that generate them, (2) we introduce novel algorithms that enhance the diversity of samples, and address the case of cellular topologies, (3) we perform statistical studies of the stability of the properties of pure types to alternative generative algorithms, and a joint study of the separability of pure types, in terms of their embedding in a space of metrics for network analysis, widely adopted in the social and physical sciences.We conclude with a word of caution to the practitioners, who sample pure topology types to assess the "statistical significance" of their findings, e.g., the p-value of the clustering coefficient is sensitive to the sampling algorithm used. We find that different pure types share similar topological properties. Further, real world networks hardly present the variability profile of a single pure type. We suggest the assumption of "mixtures of types" as an alternative starting point for developing models and algorithms for network analysis.
Dynamic social network analysis using latent space models
Authors: Sarkar Purnamrita , Moore Andrew W.
Published: January 2007

This paper explores two aspects of social network modeling. First, we generalize a successful static model of relationships into a dynamic model that accounts for friendships drifting over time. Second, we show how to make it tractable to learn such models from data, even as the number of entities
n
gets large. The generalized model associates each entity with a point in
p
-dimensional Euclidean latent space. The points can move as time progresses but large moves in latent space are improbable. Observed links between entities are more likely if the entities are close in latent space. We show how to make such a model tractable (sub-quadratic in the number of entities) by the use of appropriate kernel functions for similarity in latent space; the use of low dimensional KD-trees; a new efficient dynamic adaptation of multidimensional scaling for a first pass of approximate projection of entities into latent space; and an efficient conjugate gradient update rule for non-linear local optimization in which amortized time per entity during an update is
O
(log
n
). We use both synthetic and real-world data on up to 11,000 entities which indicate near-linear scaling in computation time and improved performance over four alternative approaches. We also illustrate the system operating on twelve years of NIPS co-authorship data.
The case for anomalous link discovery
Authors: Rattigan Matthew J. , Jensen David
Published: January 2007

In this paper, we describe the challenges inherent to the task of
link prediction
, and we analyze one reason why many link prediction models perform poorly. Specifically, we demonstrate the effects of the extremely large class skew associated with the link prediction task. We then present an alternate task ---
anomalous link discovery
(ALD) --- and qualitatively demonstrate the effectiveness of simple link prediction models for the ALD task. We show that even the simplistic structural models that perform poorly on link prediction can perform quite well at the ALD task.
Discovering informative connection subgraphs in multi-relational graphs
Authors: Ramakrishnan Cartic , Milnor William H. , Perry Matthew , Sheth Amit P.
Published: January 2007

Discovering patterns in graphs has long been an area of interest. In most approaches to such pattern discovery either quantitative anomalies, frequency of substructure or maximum flow is used to measure the interestingness of a pattern. In this paper we introduce heuristics that guide a subgraph discovery algorithm away from banal paths towards more "informative" ones. Given an RDF graph a user might pose a question of the form:
"What are the most relevant ways in which entity X is related to entity Y?"
the response to which is a subgraph connecting
X
to
Y.
We use our heuristics to discover informative subgraphs within RDF graphs. Our heuristics are based on weighting mechanisms derived from edge semantics suggested by the RDF schema. We present an analysis of the quality of the subgraphs generated with respect to path ranking metrics. We then conclude presenting intuitions about which of our weighting schemes and heuristics produce higher quality subgraphs.
Privacy-enhanced linking
Authors: Sweeney Latanya
Published: January 2007

While computer scientists are uniquely situated to incorporate privacy protections in the link analysis algorithms they construct, most computer scientists are unaware of this opportunity and of ways to think about achieving needed protections. The work presented in this writing introduces a new way for computer scientists to think about providing privacy protection within link analysis and introduces the notion of "privacy-enhanced linking" as algorithms that perform link analysis with guarantees of privacy protection modeled after the Fair Information Practices. In this approach, privacy protection is realized by assessing the validity and interpretation of link analysis results such that inappropriate harm to individuals is provably minimized.
Q
2
C@UST
Authors: Shen Dou , Pan Rong , Sun Jian-Tao , Pan Jeffrey Junfeng , Wu Kangheng , Yin Jie , Yang Qiang
Published: January 2007

In this paper, we describe our ensemble-search based approach,
Q
2
C
@
UST
(
http://webprojectl.cs.ust.hk/q2c/
), for the query classification task for the KDDCUP 2005. There are two aspects to the key difficulties of this problem: one is that the meaning of the queries and the semantics of the predefined categories are hard to determine. The other is that there are no training data for this classification problem. We apply a two-phase framework to tackle the above difficulties. Phase I corresponds to the training phase of machine learning research and phase II corresponds to testing phase. In phase I, two kinds of classifiers are developed as the base classifiers. One is synonym-based and the other is statistics based. Phase II consists of two stages. In the first stage, the queries are enriched such that for each query, its related Web pages together with their category information are collected through the use of search engines. In the second stage, the enriched queries are classified through the base classifiers trained in phase I. Based on the classification results obtained by the base classifiers, two ensemble classifiers based on two different strategies are proposed. The experimental results on the validation dataset help confirm our conjectures on the performance of the Q2C@UST system. In addition, the evaluation results given by the KDDCUP 2005 organizer confirm the effectiveness of our proposed approaches. The best F1 value of our two solutions is 9.6% higher than the best of all other participants' solutions. The average F1 value of our two submitted solutions is 94.4% higher than the average F1 value from all other submitted solutions.
The Ferrety algorithm for the KDD Cup 2005 problem
Authors: Kardkovács Zsolt T. , Tikk Domonkos , Bánsághi Zoltán
Published: January 2007

In this paper, we present a general solution for the KDD Cup 2005 problem. It uses the Internet as source of knowledge and extends it to categorize very short (less than 5 words) documents with reasonable accuracy. Our approach consists of three main parts: i.) a central knowledge filter ii.) an on-demand web crawler and iii.) a very efficient categorizer system. Our solution obtained Creativity and Precision Runner-up Awards at the competition. The main idea of Ferrety Algorithm can be generalized for mapping one taxonomy to another if training documents are available.
Open source data mining
Authors: Goethals Bart , Nijssen Siegfried , Zaki Mohammed J.
Published: January 2007

Over the past decade tremendous progress has been made in data mining methods like clustering, classification, frequent pattern mining, and so on. Unfortunately, however, the advanced implementations are often not made publicly available, and thus the results cannot be independently verified. We believe that this hampers the rapid advances in the field. With this workshop we intended to promote open source data mining (OSDM) by creating a first meeting place to discuss open source data mining methods.
Report on UBDM-05
Authors: Weiss Gary , Saar-Tsechansky Maytal , Zadrozny Bianca
Published: January 2007

In this report we provide a summary of the First International Workshop on Utility-Based Data Mining (UBDM-05) held in conjunction with the 11
th
ACM SIGKDD International Conference on Knowledge Discovery and Data Mining. The workshop was held on August 21, 2005 in Chicago, IL, USA. This workshop was geared toward researchers with an interest in how economic utility factors affect data mining (e.g., researchers in cost-sensitive learning and active learning) and practitioners who have real-world experience with how these factors influence data mining applications.
Mobile ad hoc networking and the IETF
Authors: Chakeres Ian D. , Macker Joseph P.
Published: January 2007

This article is part of a continuing series to discuss ongoing activities within the mobile ad hoc networking (MANET) working group (WG) of the IETF. This article provides a brief overview of recent events.
Developing adaptive auction mechanisms
Authors: Pardoe David , Stone Peter
Published: January 2007

Mechanism design has traditionally been a largely analytic process, relying on assumptions such as fully rational bidders. In practice, however, these assumptions may not hold, making bidder behavior difficult to model and complicating the design process. To address this issue, we propose a different approach to mechanism design. Instead of relying on analytic methods that require specific assumptions about bidders, our approach is to create a self-adapting mechanism that adjusts auction parameters in response to past auction results. In this paper, we describe our approach and then present an example of its implementation to illustrate its efficacy.
Detection tests for identifying violators of multi-party contracts
Authors: Xu Lai , Jeusfeld Manfred A. , Grefen Paul W. P. J.
Published: January 2007

In the modern business world, business coordinations are becoming complex and global. Contractual relations are required to explicitly define the collaboration between parties, certainly in scenarios with more than two parties. Therefore, execution of multi-party contracts has to be considered a vital point for successful business coordinations. However, there is little known about how to formally model a multi-party contract. The need for a multi-party contract model is thus becoming evident. In this paper, we investigate how to model a contract involving multilateral relations such that finding the responsible parties for given contract violations is facilitated. We provide algorithms for detecting violations and identifying the violator.
From an ebXML BPSS choreography to a BPEL-based implementation
Authors: Kim Ja-Hee , Huemer Christian
Published: January 2007

ebXML and Web Services are two well accepted technologies to implement business collaborations. In this paper we concentrate on the choreography of business collaborations. The corresponding standards of ebXML and Web Services are BPSS and BPEL, respectively. We present when and why we need to transform between these two standards. For the transformation we examine the difference between them. Furthermore, we suggest guidelines for a transformation from BPSS to BPEL.
Construction of negotiation protocols for e-commerce applications
Authors: Zlatev Zlatko , Diakov Nikolay , Pokraev Stanislav
Published: January 2007

A company doing e-business needs capabilities to negotiate electronically the parameters of its deals in order to fully utilize the potential of the Information and Communication technology (ICT). This paper focuses on construction of negotiation protocols for e-commerce with the following properties: (a) formal semantics, (b) compositionally constructed, and (c) dynamically reconfigurable. We apply the Reo coordination language to demonstrate that one can specify and implement negotiation protocols possessing the desired properties.
A framework for representing navigational patterns as full temporal objects
Authors: Udechukwu Ajumobi , Barker Ken , Alhajj Reda
Published: January 2007

Navigational patterns have applications in several areas including: web personalization, recommendation, user-profiling and clustering, etc. Most existing works on navigational pattern-discovery give little consideration to the effects of time (or temporal trends) on navigational patterns. Some recent works have proposed frameworks for partial temporal representation of navigational patterns. This paper proposes a framework that models navigational patterns as full temporal objects that may be represented as time series. Such a representation allows a rich array of analysis techniques to be applied to the data. The proposed framework also enhances the understanding and interpretation of discovered patterns, and provides a rich environment for integrating the analysis of navigational patterns with data from the underlying organizational environments and other external factors. Such integrated analysis is very helpful in understanding navigational patterns (e.g., E-commerce sites may integrate the trend analysis of navigational patterns with other market data and economic indicators). To achieve full temporal representation, this paper proposes a navigational pattern-discovery technique that is not based on pre-defined thresholds. This is a shift from existing techniques that are driven by pre-defined thresholds that can only support partial temporal representation of navigational patterns.
A multi-party contract model
Authors: Xu Lai
Published: January 2007

Contracts between multiple business parties play an increasingly important role in the global economy where activities along the value chain are executed by independent, yet co-operating, companies. Information technology to enact a value chain is now being deployed in the form of ERP systems, workflow systems, web services and e-marketplaces. However, there is little known on how to formally model a multi-party contract. In this paper, we investigate how to model a multi-party contract in a manner convenient for detecting the parties responsible for contract violations.
Using caching for browsing anonymity
Authors: Shubina Anna M. , Smith Sean W.
Published: January 2007

Privacy-providing tools, including tools that provide anonymity, are gaining popularity in the modern world. Among the goals of their users is avoiding tracking and profiling. While some businesses are unhappy with the growth of privacy-enhancing technologies, others can use lack of information about their users to avoid unnecessary liability and even possible harassment by parties with contrary business interests, and to gain a competitive market edge.Currently, users interested in anonymous browsing have the choice only between single-hop proxies and the few more complex systems that are available. These still leave the user vulnerable to long-term intersection attacks.In this paper, we propose a caching proxy system for allowing users to retrieve data from the World-Wide Web in a way that would provide recipient unobservability by a third party and sender unobservability by the recipient and thus dispose with intersection attacks, and report on the prototype we built using Google.
Overcoming free-riding behavior in peer-to-peer systems
Authors: Feldman Michal , Chuang John
Published: January 2007

While the fundamental premise of peer-to-peer (P2P) systems is that of voluntary resource sharing among individual peers, there is an inherent tension between individual rationality and collective welfare that threatens the viability of these systems. This paper surveys recent research at the intersection of economics and computer science that targets the design of distributed systems consisting of rational participants with diverse and selfish interests. In particular, we discuss major findings and open questions related to free-riding in P2P systems: factors affecting the degree of free-riding, incentive mechanisms to encourage user cooperation, and challenges in the design of incentive mechanisms for P2P systems.
Opportunistic scheduling in a constraint-rich world
Authors: Johnstone David , Bradley Steven
Published: January 2007

The latest planners and schedulers allow expressive domain modelling and problem definition, particularly with respect to the inclusion of constrained resource usage and inter-task dependencies. This increased complexity removes the ability to guarantee schedulability of a problem at run-time.In hard real-time systems, where 'hard' emphasizes the critical nature of meeting task deadines, the estimated worst-case execution time is used in the task representation. If a solely static framework is used to schedule these systems, the pessimism in the prediction of task execution times will lead to unused resources.This paper describes a framework to include a local dynamic scheduler with a large-scale planner or scheduler. The local scheduler can take advantage of any unused resources by scheduling additional task sets. It can also handle online plan repair by switching between different quality levels of tasks.