ppxscal/embedding_network huggingface dataset:
Graph kernels and Gaussian processes for relational reinforcement learning
Authors: Kurt Driessens, Jan Ramon, Thomas Gärtner
Venue: Machine Learning (2006)

RRL is a relational reinforcement learning system based on Q-learning in relational state-action spaces. It aims to enable agents to learn how to act in an environment that has no natural representation as a tuple of constants. For relational reinforcement learning, the learning algorithm used to approximate the mapping between state-action pairs and their so called Q(uality)-value has to be very reliable, and it has to be able to handle the relational representation of state-action pairs. In this paper we investigate the use of Gaussian processes to approximate the Q-values of state-action pairs. In order to employ Gaussian processes in a relational setting we propose graph kernels as a covariance function between state-action pairs. The standard prediction mechanism for Gaussian processes requires a matrix inversion which can become unstable when the kernel matrix has low rank. These instabilities can be avoided by employing QR-factorization. This leads to better and more stable performance of the algorithm and a more efficient incremental update mechanism. Experiments conducted in the blocks world and with the Tetris game show that Gaussian processes with graph kernels can compete with, and often improve on, regression trees and instance based regression as a generalization algorithm for RRL.
Kasturi Voted 2007 Computer Society President-Elect: Board of Governors Members and New Vice Presidents also Named
Authors: Bob Ward
Venue: Computer (2006)

IEEE Computer Society members recently selected Rangachar Kasturi to serve as the Society's president-elect for 2007.
Information gathering support interface by the overview presentation of web search results
Authors: Takumi Kobayashi, Kazuo Misue, Buntarou Shizuki, Jiro Tanaka
Venue: Proceedings of the 2006 Asia-Pacific Symposium on Information Visualisation - Volume 60 (2006)

The Internet consists of several billion documents. Choosing information from such a great number of Web pages is not easy. We do not think that the interfaces of traditional search engines that divide search results into dozens of pages regardless of genre and display the results as a text-based list are necessarily useful. We propose an interface that helps the user to intuitively understand the entire Web search result and to gather information. Our system analyzes and classifies Web search results and presents the classification results to the user on one screen.
A unified approach for finite-dimensional, rare-event Monte Carlo simulation
Authors: Zhi Huang, Perwez Shahabuddin
Venue: Proceedings of the 36th conference on Winter simulation (2004)

We consider the problem of estimating the small probability that a function of a finite number of random variables exceeds a large threshold. Each input random variable may be light-tailed or heavy-tailed. Such problems arise in financial engineering and other areas of operations research. Specific problems in this class have been considered earlier in the literature, using different methods that depend on the special properties of the particular problem. Using the Laplace principle (in a restricted finite-dimensional setting), this paper presents a unified approach for deriving the log-asymptotics, and developing provably efficient fast simulation techniques using the importance sampling framework of hazard rate twisting.
An architecture for componentized, network-based media services
Authors: M. Harville, M. Covell, S. Wee
Venue: Proceedings of the 2003 International Conference on Multimedia and Expo - Volume 1 (2003)

We present MSA (media services architecture), a flexible, general architecture for requesting, configuring, and running services that operate on streaming audio and video as it flows through the network. MSA decomposes requested media services into modular processing components that may be distributed to servers throughout the network and which intercommunicate via standard streaming protocols. Use of standard protocols also affords seamless interoperability between MSA and media content delivery networks. MSA manages media services by monitoring the networked servers and assigning service components to them in a manner that uses available computational and network resources efficiently. We describe some implemented example services to illustrate the concepts and benefits of the architecture.
Quantum stochastic Weyl operators
Authors: L. Accardi, A. Boukas
Venue: Proceedings of the 2003 International Conference on Physics and Control - Volume 3 (2003)

The quantum stochastic differential equation satisfied by the unitary operator U(t) = e/sup iE(t)/ with E(t) = /spl lambda/t + z B/sub t//sup -/ + z~ B/sub t//sup +/ + k M/sub t/, where B/sub t//sup -/, B/sub t//sup +/, and M/sub t/ are the square of white noise processes, is obtained in the module form.
Agile management of uncertain requirements via generalizations: a case study
Authors: Karl Reed, Ernesto Damiani, Gabriele Gianini, Alberto Colombo
Venue: Proceedings of the 2004 workshop on Quantitative techniques for software agile process (2004)

A major justification for the agile class of software processes is that customer requirements often change substantially during development, with the result that developers must work with a ever-changing specification. The best way of dealing with this, it is claimed, is a process including adaptive and iterative steps allowing the code under development to change to meet an evolving requirement. In this paper, we use quantitative process data to argue that the deliberate development of an evolvable design, based upon extensions and variations to the requirements, and the generality derivable from the implemented system, may provide agility within a more traditional development, showing that the two concepts are interchangeable, to some extent. In doing so, the paper draws upon our joint work on evolvable systems, and upon a concept developed by one of us in the 1980's, "The Contraction of Generality", to illustrate the alternatives.
Contextual Modulation of Amygdala Responsivity to Surprised Faces
Authors: Hackjin Kim, Leah H. Somerville, Tom Johnstone, Sara Polis, Andrew L. Alexander, Lisa M. Shin, Paul J. Whalen
Venue: Journal of Cognitive Neuroscience (2004)

We recently demonstrated a functional relationship between fMRI responses within the amygdala and the medial prefrontal cortex based upon whether subjects interpreted surprised facial expressions positively or negatively. In the present fMRI study, we sought to assess amygdala&ndash;medial prefrontal cortex responsivity when the interpretations of surprised faces were determined by contextual experimental stimuli, rather than subjective judgment. Subjects passively viewed individual presentations of surprised faces preceded by either a negatively or positively valenced contextual sentence (e. g., She just found &dollar;500 vs. She just lost &dollar;500). Negative and positive sentences were carefully matched in terms of length, situations described, and arousal level. Negatively cued surprised faces produced greater ventral amygdala activation compared to positively cued surprised faces. Responses to negative versus positive sentences were greater within the ventrolateral prefrontal cortex, whereas responses to positive versus negative sentences were greater within the ventromedial prefrontal cortex. The present study demonstrates that amygdala response to surprised facial expressions can be modulated by negatively versus positively valenced verbal contextual information. Connectivity analyses identified candidate cortical&ndash;subcortical systems subserving this modulation.
Broadcasting in Optimal Bipartite Double Loop Graphs
Authors: H. A. Harutyunyan, E. Maraachlian
Venue: Proceedings of the conference on Information Visualization (2006)

Double loop graphs are extensions of the ring topology which are obtained by regularly adding 2 extra edges per vertex. An optimal graph of diameter d has the maximum possible number of vertices. The optimal structure of double loop graphs, as well as the broadcast time and an optimal broadcast scheme are known. In this paper, we define the family of bipartite double loop graphs (BDLG) G = (V,E) where V = V_0 u V_1, V_0 n V_1 = f and |V0| = |V1|. We show that the maximum number of vertices that a BDLG of diameter d can have is 2d2. We also study the broadcast problem and find that the broadcast time is d + 2. Finally we present an optimal broadcast scheme for these bipartite double loop graphs.
Guest Editors' Introduction
Authors: John Weckert, Richard George, Thomas B. Hodel
Venue: Ethics and Information Technology (2006)

This paper discusses privacy and the monitoring of e-mail in the context of the international nature of the modern world. Its three main aims are: (1) to highlight the problems involved in discussing an essentially philosophical question within a legal framework, and thus to show that providing purely legal answers to an ethical question is an inadequate approach to the problem of privacy on the Internet; (2) to discuss and define what privacy in the medium of the Internet actually is; and (3) to apply a globally acceptable ethical approach of international human rights to the problem of privacy on the Internet, and thus to answer the question of what is and is not morally permissible in this area, especially in light of recent heightened concerns about terrorist activities. It concludes that the monitoring of e-mail is, at least in the vast majority of cases, an unjustified infringement of the right to privacy, even if this monitoring is only aimed at preventing the commission of acts of terrorism.
Systems without low-productive sources
Authors: Leo Egghe, Ronald Rousseau
Venue: Information Processing and Management: an International Journal (2006)

Information production processes (IPPs) without low-productive sources are studied. A success-breeds-success or preferential attachment mechanism is established in which, from some point in time on, no new sources are created. Such systems are called mature systems. When time increases in mature systems the expected number of sources with a low number of items strictly decreases. An adaptation of the Naranan-Egghe model indicates that IPPs without low-productive sources must have small alpha exponents (α<2) in their size-frequency power law descriptions.A positive reinforcement model explains all the essential properties. Using this approach it is shown that, when time increases in mature systems the alpha exponent of the power size-frequency function decreases, while, moreover, the minimum source size increases. This is the main result of this article.Examples related to country and city sizes illustrate the concepts and results discussed in this article.
Modified MP3 encoder using complex modified cosine transform
Authors: M. Mathew, V. Bhat, S. M. Thomas, Changhoon Yim
Venue: Proceedings of the 2003 International Conference on Multimedia and Expo - Volume 1 (2003)

MPEG-1 layer-3, popularly known as MP3, has revolutionized the digital music domain. MP3 makes use of psychoacoustic modeling to achieve compression through the removal of perceptually irrelevant components of digital audio. The psychoacoustic model is the key element of perceptual coding and requires intensive FFT computation for calculating the frequency spectrum. This spectrum is used to compute masking thresholds. Thus, the original MP3 algorithm computes modified discrete cosine transform (MDCT) and FFT parallelly. The proposed algorithm is an alternative to this. We make use of complex modified discrete cosine transform (CMDCT) of the filter-bank outputs for generating MDCT coefficients as well as the frequency spectrum. This method requires fewer computations than the original method. A novel method of window switching, based on filter-bank output is used to simplify the overall algorithm. The proposed algorithm reduces the amount of computations for MP3 encoder while retaining the audio quality.
Mathematical applications of inductive logic programming
Authors: Simon Colton, Stephen Muggleton
Venue: Machine Learning (2006)

The application of Inductive Logic Programming to scientific datasets has been highly successful. Such applications have led to breakthroughs in the domain of interest and have driven the development of ILP systems. The application of AI techniques to mathematical discovery tasks, however, has largely involved computer algebra systems and theorem provers rather than machine learning systems. We discuss here the application of the HR and Progol machine learning programs to discovery tasks in mathematics. While Progol is an established ILP system, HR has historically not been described as an ILP system. However, many applications of HR have required the production of first order hypotheses given data expressed in a Prolog-style manner, and the core functionality of HR can be expressed in ILP terminology. In Colton (2003), we presented the first partial description of HR as an ILP system, and we build on this work to provide a full description here. HR performs a novel ILP routine called Automated Theory Formation, which combines inductive and deductive reasoning to form clausal theories consisting of classification rules and association rules. HR generates definitions using a set of production rules, interprets the definitions as classification rules, then uses the success sets of the definitions to induce hypotheses from which it extracts association rules. It uses third party theorem provers and model generators to check whether the association rules are entailed by a set of user supplied axioms.HR has been applied successfully to a number of predictive, descriptive and subgroup discovery tasks in domains of pure mathematics. We survey various applications of HR which have led to it producing number theory results worthy of journal publication, graph theory results rivalling those of the highly successful Graffiti program and algebraic results leading to novel classification theorems. To further promote mathematics as a challenge domain for ILP systems, we present the first application of Progol to an algebraic domain--we use Progol to find algebraic properties of quasigroups, semigroups and magmas (groupoids) of varying sizes which differentiate pairs of non-isomorphic objects. This development is particularly interesting because algebraic domains have been an important proving ground for both deduction systems and constraint solvers. We believe that AI programs written for discovery tasks will need to simultaneously employ a variety of reasoning techniques such as induction, abduction, deduction, calculation and invention. We argue that mathematics is not only a challenging domain for the application of ILP systems, but that mathematics could be a good domain in which to develop a new generation of systems which integrate various reasoning techniques.
Direct Marketing When There Are Voluntary Buyers
Authors: Yi-Ting Lai, Ke Wang, Daymond Ling, Hua Shi, Jason Zhang
Venue: Proceedings of the Sixth International Conference on Data Mining (2006)

In traditional direct marketing, the implicit assumption is that customers will only purchase the product if they are contacted. In real business environments, however, there are "voluntary buyers," who will still make the purchase in the absence of a contact. While no direct promotion is needed for voluntary buyers, the traditional response-driven paradigm tends to target such customers. This paper presents "influential marketing," targeting only those whose purchase decisions can be positively influenced, i.e. buyers who are non-voluntary. Our novel, practical solution to this problem gives promising results.
Inhibitors to personal digital assistant adoption in healthcare: a secondary analysis of the research literature, 1995--2005
Authors: Yvonne J. Kochanowski
Venue:  (2006)

Personal digital assistants (PDAs) have become a valuable communication tool for physicians by allowing them to have instant access to clinical references; to calculate important parameters; and to retrieve, record, and store patient data at the point-of-care. Despite the apparent efficacy of PDA-based point-of-care systems, research has indicated that the PDA adoption rate in healthcare sector slowed during 2004. This study employed secondary analysis of published research studies involving PDA-based systems implementation in a clinical setting from 1995 to June 2005 to examine the barriers that discourage PDA adoption by healthcare practitioners. The sample included 121 studies---83 conducted in the United States, 18 in Canada, 11 in Europe, and 9 in Asia. As a secondary analysis study, this research used a combination of quantitative and qualitative perspectives with cross-tabulation, chi-square analysis, Fisher's exact test, and content analysis techniques. Following Ajzen's theory of planned behavior, Davis' technology acceptance model, and DeLone and McLean's updated information systems success model, the barriers identification process was focused on the following major factors influencing potential and existing users' decisions toward use of particular technology: (a) perceived usefulness, (b) ease of use, (c) behavioral beliefs and outcome evaluations, (d) normative beliefs and motivation to comply, (e) control beliefs and perceived facilitation, and (f) service quality. The study found that the tested barriers to PDA adoption had been changing during the last decade. The changing trends were qualitatively different in clinician surveys compared to experiments in the clinical setting and in experiments with Pocket PCs compared to experiments with Palm OS devices. Based on the findings of this investigation, recommendations for healthcare organizations and PDA technology vendors were provided to facilitate increased PDA usage by healthcare practitioners.
CSCL as a catalyst for changing teacher practice
Authors: Paul Resta, Mark Christal, Karen Ferneding, Adrienne Kennedy Puthoff
Venue: Proceedings of the 1999 conference on Computer support for collaborative learning (1999)

This paper presents results of a study of middle school teachers using a prototype Macintosh version of CSILE to help create a knowledge-building community. The study, involving middle schools in two school districts in the Southwest United States, provided teachers with training and technical support in the use of the CSILE over a period of one semester.In-depth interviews were conducted with the teacher participants a year after the termination of the project to understand their experiences and to learn their stories of the impact of the Knowledge-Building Community Project on their teaching practices. Five major themes emerged from the analysis of the interview transcription data. This paper presents a summary of the teacher reflections and stories related to the emergent theme of how the knowledge-building community changed their teaching practices, roles, the structure of their classroom discourse, and their views of curriculum. The results of the study suggest that CSILE, accompanied by appropriate support, can serve as a catalyst in changing teacher practices from didactic teaching to more constructivist approaches to learning. The paper presents teacher reflections on changes in their roles, views of curriculum and classroom discourse as a result of the knowledge-building community project.
Generative unbinding of names
Authors: Andrew M. Pitts, Mark R. Shinwell
Venue: ACM SIGPLAN Notices (2007)

This paper is concerned with a programming language construct for typed name binding that enforces αequivalence. It proves a new result about what operations on names can co-exist with this construct. The particular form of typed name binding studied is that used by the FreshML family of languages. Its characteristic feature is that a name binding is represented by an abstract (name,value)-pair that may only be deconstructed via the generation of fresh bound names. In FreshML the only observation one can make of names is to test whether or not they are equal. This restricted amount of observation was thought necessary to ensure that there is no observable difference between αequivalent name binders. Yet from an algorithmic point of view it would be desirable to allow other operations and relations on names, such as a total ordering. This paper shows that, contrary to expectations, one may add not just ordering, but almost any relation or numerical function on names without disturbing the fundamental correctness result about this form of typed name binding (that object-level αequivalence precisely corresponds to contextual equivalence at the programming meta-level), so long as one takes the state of dynamically created names into account.
Building computational grids with apple's Xgrid middleware
Authors: Baden Hughes
Venue: Proceedings of the 2006 Australasian workshops on Grid computing and e-research - Volume 54 (2006)

Apple's release of the Xgrid framework for distributed computing introduces a new technology solution for loosely coupled distributed computation. In this paper systematically describe, compare and evaluate the Apple native Xgrid solution and a range of third party components which can be substituted for the native versions. This description and evaluation is grounded in practical experience of deploying a small scale, internationally distributed, heterogenous computational infrastructure based on the Xgrid framework.
On Choosing Wavelet Resolution in Image Deblurring
Authors: Laurent Cavalier, Marc Raimondo
Venue: Proceedings of the International Conference on Computer Graphics, Imaging and Visualisation (2006)

In wavelet deblurring of noisy images the finest resolution levels are key parameters which require fine tuning. In this paper we present a blockwise thresholding rule in the Fourier domain to derive near-optimal finest resolution levels for a large class of blurred-image scenarios. Numerical results based on the WaveD fast algorithm of [5] illustrate the improvement over the current WaveD setting.
Parameter identifiability of multichannel ARMA models of linear non-Gaussian signals via cumulant matching
Authors: J. K. Tugnait
Venue: Proceedings of the Acoustics, Speech, and Signal Processing,1994. on IEEE International Conference - Volume 04 (1994)

The problem of estimating the parameters of a vector, stationary, ARMA(p,q) signal model driven by an i.i.d. vector non-Gaussian sequence is considered. The paper's focus is the problem of parameter identifiability of multichannel ARMA models given the higher-order cumulants of the signal on a finite set of lags. We specify the finite lag set for general ARMA(p,q) models. Our approach is to first derive the basic results via a diagonal canonical form and then to extend the parameter identifiability results to other (more parsimonious) canonical forms.
A deterministic solver for the transport of the AlGaN/GaN 2D electron gas including hot-phonon and degeneracy effects
Authors: M. Galler, F. Schürrer
Venue: Journal of Computational Physics (2005)

The transport of the two-dimensional electron gas formed at an AlGaN/GaN heterostructure in the presence of strain polarization fields is investigated. For this purpose, we develop a deterministic multigroup model to the Boltzmann transport equations. The envelope wave functions for the confined electrons are calculated using a self-consistent Poisson-Schrodinger solver. The electron gas degeneracy and hot phonons are included in our transport equations. Numerical results are given for the dependence of macroscopic quantities on the electric field strength and on time and for the electron and phonon distribution functions. We compare our results to those of Monte Carlo simulations and with experiments.