Research Sites and Groups

Last Updated: 5 January 2010

Site maintained by:

Leigh Tesfatsion

Department of Economics

Iowa State University

Ames, Iowa 50011-1070

http://www.econ.iastate.edu/tesfatsi/

tesfatsi AT iastate.edu

Agent-Based Computational Economics (ACE) Website:

http://www.econ.iastate.edu/tesfatsi/ace.htm

• Agent-Based Computational Economics (ACE)
• Economic and Social Network Formation
• Evolution
• Complex Adaptive Systems (CAS)
• Artificial Life and Artificial Intelligence
• Learning and Human Cognition
• Evolutionary Computation
• Demos, Software, and Software Development
• Commercial Development and Application
• Miscellaneous

Sites of Particular Interest for ACE

• A website on Agent-Based Computational Economics, maintained by Leigh Tesfatsion (Economics, Iowa State University), provides pointers to various ACE-related resources, including: surveys; an annotated syllabus of readings; software and toolkits; interactive computer demos; journals; and pointers to individual researchers and research groups. This site has been designated as a select learning resource by the Scout Report for Business and Economics (January 29, 1998).

• A website on Agent-Based Computational Finance has been constructed by Blake LeBaron (Economics, Brandeis University). Agent-based computational finance is an application of agent-based computational methods to finance and financial markets. This area borrows heavily on methods developed in other agent-based economic environments. The web site is designed to give researchers interested in this area a starting point in terms of finding relevant online materials. Resources incorporated to date include pointers and paper lists.

• A website on Agent-Based Modeling of Restructured Electricity Markets has been constructed by Leigh Tesfatsion (Economics, Iowa State University). Resources provided at this site include a listing of key issues, readings, software, and pointers to individual researchers and research groups.

• The Center for Nonlinear Dynamics in Economics and Finance (CeNDEF) is a multi-disciplinary research institute started in 1998 and located at the Department of Economics and Econometrics at the University of Amsterdam. Research topics addressed by CeNDEF participants include: endogenous fluctuations; bounded rationality; expectation formation and learning, evolutionary dynamics, bifurcations and chaos, nonlinear time series analysis, and nonlinear prediction methods.

• From an announcement by Edward Tsang (University of Essex, U.K.): The Centre for Computational Finance and Economic Agents (CCFEA) is an interdisciplinary laboratory-based centre located at the University of Essex. CCFEA is a showcase for cutting-edge computational and evolutionary methods to simulate artificially intelligent agents in markets and other complex economic environments. Students pursuing the new CCFEA MScs and the established CCFEA Doctoral Program leading to a Ph.D. in Computational Finance will receive rigorous training in the principles of quantitative finance and microeconomics along with computational skills.

• Blake LeBaron (Brandeis University) maintains a list of pointers to Finance Sites (Interactive, Java) that permit users to enter their own information, test hypotheses, watch actual data move across the screen, and perform many other interactive functions.

• Robert Goldston, Allen Lee, and Andy Jones (Percepts and Concepts Laboratory, Indiana University, Bloomington) are encouraging people to participate in an ongoing on-line group experiment on resource foraging accessible at the Group Experimentation Environment (GEE) Project Site. They describe the experiment as follows: "The experiment is rather educational and engrossing. Your goal in a four-minute experiment is to pick up as many resources as you can by moving your icon with the arrow keys. You compete against other humans when they are available or Artificial Intelligence Bots (programmed by Michael Roberts) when no other humans are currently on-line. We have been beta-testing the environment locally at Indiana University for awhile, and now feel ready to announce it to the broader community, at least the broader ACADEMIC community at this point. If you find any bugs or have suggestions for improvements, please email Andy Jones or Allen Lee , and CC me (rgoldsto@indiana.edu)."

• Franco Buscetti (geocities.com) maintains a web site focusing on heuristics and artificial intelligence in finance and investment. The site provides annotated pointers to articles, databases, and other materials in five main areas: General optimization and AI resources; neural networks; genetic algorithms; tabu search, and simulated annealing.

• Allan Schmid (Michigan State University) maintains a site titled Institutional Economics. The purpose of the site is to facilitate exchange of ideas on institutional and behavioral economics (both old and new). Resources provided at the site include links to working papers, reviews, course outlines, and conference announcements.

• The LABORatorio Riccardo Revelli, associated with the University of Torino and funded by the Compagnia di San Paolo, uses agent-based models to study labor market and industrial dynamics issues. Issues of particular interest include the operation of European labor markets, and the evaluation of policy options aimed at dealing with employment problems in the EU.

• The Institute for Empirical Research in Economics (Zurich, Switzerland), headed by Prof. Dr. Ernst Fehr, maintains a web site on Microeconomics and Experimental Economics. Institute researchers combine insights from modern economic theory with results from social psychology and sociology to understand important economic phenomena. Topics stressed include the functioning of labor markets, the organization of the modern corporation, the private and public provision of public goods, and intertemporal choice problems. Classes are offered in labor economics, experimental economics, applied microeconomics, and game theory.

• The Interdisciplinary Center for Economic Science (ICES) at the Arlington, Virginia campus of George Mason University uses human-subject laboratory experiments to test economic theories. The ICES moved to GMU in 2001 from the University of Arizona, where it was known as the Economic Science Laboratory.

• Professor Charles A. Holt (Department of Economics, University of Virginia) maintains a site titled the Y2K Bibliography of Experimental Economics and Social Science that lists exactly 2000 publications in experimental economics and social science, together with about 500 discussion papers. Each entry is arranged by keyword topic. The database can be searched by author or keyword.

• Al Roth (Harvard University) maintains an extensive informative web site on Game Theory and Experimental Economics.

• Robert Axelrod (University of Michigan, Ann Arbor, MI) maintains a website on Agent-Based Models of Conflict and Collaboration.

• Nicholas Gessler (Department of Anthropology, UCLA, Los Angeles) maintains an interesting unusual website titled Artificial Culture: Experiments in Synthetic Anthropology. Resources provided at this student-oriented site include course syllabi, conference information, numerous illustrative executable simulations in C++ (with links, explanations, source code, and zipped Borland project files), and tutorial materials covering simulation basics.

• A group of researchers at Carnegie Mellon maintains a ComLabGames Site. This site provides a variety of software permitting instructors and students to design, run, and analyze the outcomes of games played over the Internet. Three types of game modules are offered: strategic form games; extensive form games; and market games.

• Mike Shor (Owen Graduate School of Management, Vanderbilt University) has developed a Game Theory Resource Site for educators and students of game theory. The site includes pointers to lecture notes, news, interactive materials, text book reviews, pop culture use of game theory, games, quizzes and tests, and related links.

• A web site on Coordination Games: Complementarities and Macroeconomics is maintained by Russell Cooper (Boston University, Boston, MA) to accompany his book of the same title from Cambridge University Press, 1999.

• Ariel Rubinstein and Eli Zvuluny (School of Economics, Tel Aviv University, and Princeton University, New Jersey) maintain a website titled Didactic Web-Based Experiments in Game Theory. The purpose of the site is to provide the teachers of basic game theory courses with free user-friendly didactic tools for conducting web-based thought experiments.

• Greg Delemeester and Jurgen Brauer (Marietta College, Ohio) maintain a website titled Games Economists Play which they describe as follows: "This website is a resource for instructors of economics who would like to use non-computerized economic experiments (games) in their classrooms. The bulk of the website consists of an extensively annotated and hyperlinked compilation of more than 120 classroom games, most of which can be played within one class period. The purpose of the games is to help teach fundamental micro and macroeconomic concepts. The website is organized around three tables that classify the games according to subject matter, objectives, class size, game variations, etc. A bibliographic source and/or contact reference is provided for each game. Whenever possible, each game is hyperlinked to (i) similar or related games, (ii) the author's email address, and (iii) a website where the full game description can be accessed (if available). A separate link to a complete games bibliography follows the tables."

• Carl T. Bergstrom (Department of Zoology, University of Washington, Seattle) maintains a website titled An Introduction to the Theory of Honest Signalling. Topics covered at this website include an introduction to the basic honest signalling problem, honest signalling problems in biology, honest signalling problems in economics, and the mathematics of honest signalling.

• Rod Garratt (UC Santa Barbara, California) and Guillaume Haeringer (Universitat Autonoma de Barcelona) maintain the Grand Coalition Web Site. This site provides information and resources about research in cooperative and noncooperative game theory, with an emphasis on coalition formation.

• The International Society of Dynamic Games, founded in Helsinki, Finland, in 1990, seeks to promote interactions among researchers interested in the application of dynamic games. To this end the society sponsors conferences and workshops, a newsletter, and an archival journal, Annals of Dynamic Games.

• Hal Varian (School of Information Management and Systems, UC Berkeley) maintains a web site on The Information Economy focusing on the economics of the internet, information goods, intellectual property, and related issues.

• Stanley Leibowitz (Management, University of Texas at Dallas) maintains a web site devoted to a new book by Leibowitz and Margolis titled Winners, Losers, and Microsoft. Following earlier work by W. Brian Arthur, increasing returns, network effects, path dependence, and lock-in have been prominently featured in recent economic writings and policy debates. In particular, some of the arguments advanced by government in the Microsoft antitrust case have been based on these concepts, as articulated by Arthur. Leibowitz's site provides pointers to resources that stress the meaning and application of these concepts, with particular attention paid to the Microsoft antitrust case. Leibowitz is by no means a disinterested commentator -- he comes down strongly on the side of Microsoft. Additional materials on this topic area (including pointers to articles by W. Brian Arthur) can be found at a web site maintained by Leigh Tesfatsion (Economics, Iowa State University) on Network Effects, Path dependence, and Lock-In.

• The Center for the Study of Institutions, Population, and Environmental Change (CIPEC) at Indiana University, Bloomington, is co-directed by Emilio Moran (anthropology) and Elinor Ostrom (political science). CIPEC studies processes of change in forest and other environments as mediated by institutional arrangements, demographic factors, and other major human driving forces. CIPEC includes a diversity of researchers in the social, biological, and physical sciences employing a broad range of tools (e.g., analysis, case studies, satellite and aerial photographs, household surveys, and agent-based computational modelling). For more information, visit the CIPEC Home Page.

• Dawn Parker (Department of Geology, George Mason University) maintains a resource website for researchers interested in multi-agent systems models of land-use and cover-change (MAS/LUCC). Visitors to this website will find links to literature, conferences and workshops, descriptions of ongoing research projects, and software tools.

• Steve Railsback and other researchers affiliated with the Mathematical Modeling Program at Humboldt State University in Arcata, California, are working on the agent-based simulation of ecological systems, particularly of fish communities. This research is a collaboration of mathematicians, stream ecologists, fish biologists, environmental engineers, and software professionals.

• The interdisciplinary Environmental Modelling and Monitoring Group (Department of Geography, Edinburgh University) focuses on applications that use developments in core technologies such as Geographical Information Systems (GIS), remote sensing, cartography, and Internet technologies. From the group's home page: "(For example, the group's research in environmental monitoring) involves two main themes: neotropical biogeography, and the remote sensing of aquatic systems and vegetation. Biogeography research is concentrated in the Yucatáan (Central America) and the forests and savannas of Brazil, Guyana and South America. Collaborative work is investigating how variations in soil properties can explain the spatial distribution of vegetation and form a basis for land development planning and conservation. ... The use of remote sensing in measuring biological activities is principally focused on high-spectral resolution and radar remote sensing techniques with particular attention to understanding reflectance/backscatter signals."

• Paul M. Torrens (Department of Geography, University of Utah) maintains a website on Geosimulation. Linked resources include projects focusing on adaptive industrial and business networks, urban change, pedestrian behavior, and suburban sprawl, as well as a variety of open-source cellular automata and agent-based modelling platforms.

• Gianaurelio Cuniberti (Max-Planck Institute for the Physics of Complex Systems, Dresden) and Marco Raberto (Department of Biophysics and Electronics Engineering, University of Genoa, Italy) maintain a web site that provides pointers to resources related to econophysics. From the site: "Recently the emerging field of econophysics is appearing as a new subdiscipline in physics. Although still in its infancy, the idea is to blend methods of statistical physics, nonlinear dynamics and agent based simulations to problems in the economics realm. In the past, economics has fed from successful physical theories, but now the reverse is happening and a direct interest of the physical community in those subjects has grown. ... The field has strongly developed in the areas of financial markets models and social (or economic) collective behaviour, among others."

• The aim of the InSiSoc Group (University of Valladolid, Spain) is to study and model the behaviour of complex social systems by means of the individuals' behaviour that grow the system. InSiSoc gathers experiences and contributions in multiagent systems, artificial intelligence, experimental economics and, widely speaking, the generative approach to complex social system modelling. The INSISOC Group is the team responsible for the organization of the Second European Social Simulation Conference Association.

• A computationally oriented website on Evolutionary Economics is maintained by Esben Sloth Andersen (Department of Business Studies, Aalborg University, Denmark).

• The Multiagent Systems Research Group, under the direction of Tuomas Sandholm (Computer Science Department, Washington University St. Louis), is concerned with designing, analyzing and implementing sophisticated artificial intelligence systems consisting of multiple agents. A special focus of the group is the coordination of self-interested agents in open systems. In this endeavor, use is made of techniques from game theory and other fields of microeconomics together with normative models of bounded rationality involving limited computation and communication. This work has led to the development of new techniques for single agent resource-bounded reasoning, constraint satisfaction, and machine learning. Potential applications of this work include: vehicle routing; manufacturing planning and scheduling among multiple companies in subcontracting networks; classroom scheduling; patient scheduling at hospitals; multiagent information gathering on the web; routing and bandwidth allocation in multi-provider multi-consumer computer networks; and electronic commerce.

• The Economics Web Institute is a growing hyper-text document maintained by Valentino Piana (Tiscali, Italy) that integrates downloadable simulation models, real data, and theoretical reflections. It's aim is to apply evolutionary economics and agent-based computational economics approaches to standard problems of microeconomics and macroeconomics.

• John Miller (Carnegie Mellon University) maintains a web site on Computational Economic Modelling.

• The Society for Computational Economics (SCE) supports research activities related to computational economics, the intersection between economics and computation. Included within computational economics are a variety of special interest groups focusing on areas such as agent-based computational modeling, computational econometrics and statistics, computational finance, computational modeling of dynamic macro systems, computational tools for the design of automated Internet markets, programming tools specifically designed for computational economics, and pedagogical tools for the teaching of computational economics. Resources available at the SCE home page include conference information, special interest group contact information, journal and book pointers, information regarding the SCE graduate student paper contest, and instructions for joining the SCE.

• The Association for Evolutionary Economics (AFEE) is an international organization of economists and other social scientists devoted to the analysis of economies as evolving, socially constructed, and politically governed systems. The intellectual heritage of AFEE is that of the original institutional economics created and developed by early twentieth-century economists such as Thorstein Veblen, John R. Commons, and Wesley Mitchell. The AFEE sponsors the Journal of Economic Issues, published quarterly, whose primary mission is to present articles that use and develop the core ideas of institutional economics in discussions of current economic problems and policy alternatives.

• The International Joseph A. Schumpeter Society (ISS) hosted at the University of Augsburg, Germany, was founded in 1986 at the initiative of Hanusch and Wolfgang F. Stolper. The ISS has as its principal aim the scientific study of the problems of development. Following the ideas of Schumpeter, it conceives of development as a combination of growth and structural change. The ISS seeks to foster knowledge in a scientific and non-ideological way by respecting facts as they are and not as one wishes them to be. Membership in the ISS includes a subscription to the Journal of Evolutionary Economics.

• The Computable and Experimental Economics Laboratory (CEEL), Department of Economics, University of Trento, Trento, Italy maintains a website providing general information about its experimental and computational activities.

• The Centre for Economic Learning and Social Evolution (ELSE) is an interdisciplinary research center based at University College London that promotes the study of models of interactive learning with the view of providing a new foundation for modelling behaviour in economics and related social sciences. Researchers at ELSE have a special interest in game theory and its applications.

• The IKE Group is part of the Department of Business Studies, Aalborg University, Denmark. The group does research on economic, technical, and institutional change. The main resarch themes include economic evolutionary modelling, the theory of the firm, national systems of innovation, international trade and competitiveness, and the interplay between economic and ecological issues.

• The Evolutionary Economics Group of the Max-Planck-Institute, Jena, Germany, was founded in October 1995. The group conducts research on a broad range of topics related to evolutionary phenomena in the economic domain.

• The European Association for Evolutionary Political Economy, founded in London in 1988, promotes evolutionary, dynamic, and realistic approaches to economic theory and policy.

• Researchers at the Oregon Graduate Institute of Science and Engineering in Portland, Oregon, are exploring the flow of communication and information into, within, and out of business enterprises, viewed as complex adaptive systems.

• The Society for Computer Simulation (SCS) International is a technical society devoted to the advancement of simulation and allied computer arts in all fields. The purpose of the society is to facilitate communication among professionals in the field of simulation. To this end, the society organizes meetings of regional councils, sponsors and co-sponsors national and international conferences, and publishes a monthly technical journal, Simulation, as well as a quarterly journal, the Transactions of the Society for Computer Simulation. Membership in the SCS is open to all who are or have been professionally engaged in the field of simulation.

Economic and Social Network Formation

• A resource site devoted more specifically to Agent-Based Computational Modeling of Economic Network Formation is maintained by Leigh Tesfatsion (Economics, Iowa State University).

• CASOS (Center for Computational Analysis of Social and Organizational Systems) at Carnegie Mellon University brings together computer science, dynamic network analysis, and the empirical study of complex socio-technical systems. Computational and social network techniques are combined to develop a better understanding of the fundamental principles of organizing, coordinating, managing, and destabilizing systems of intelligent adaptive agents (human and artificial) engaged in real tasks at the team, organizational, or social level. CASOS is a university-wide center drawing on faculty, students, and programming staff in multiple departments at Carnegie Mellon.

• The Coalition Theory Network (CTN) is an association of high-level scientific institutions whose aim is the advancement and diffusion of research in the area of coalition formation. The CTN, founded in 1995, sponsors annual meetings and summer school activities. The CTN is now sharing its resources with the Grand Coalition Site founded by Rod Garratt (UC Santa Barbara, California) and Guillaume Haeringer (Universitat Autonoma de Barcelona) in January 2001. The Grand Coalition Site provides information and resources about research in cooperative and noncooperative game theory, with an emphasis on coalition formation.

• An extensive resource site devoted to Economic and Social Network Formation is maintained by Leigh Tesfatsion (Economics, Iowa State University).

• A group of researchers at the University of Manchester, managed by Gillian Sinclair, is conducting research on e-Social Science, the application of grid technologies to social science research, including economics. They have funded several projects in qualitative data and one of special interest to economists entitled FINGRID. This group is also hosting the First International Conference on e-Social Science at Manchester this summer. Details about the e-Social Science project and conference can be found at the e-Social Science Website

• The Networks and Social Dynamics Research Group at Cornell University studies the effects of network topology on the dynamics of social interaction. Resources available at the research group site (maintained by Damon Centola and Michael Macy) include information about current research projects, curricula materials for a graduate seminar on agent-based modeling, and information about an upcoming (October 2005) workshop on "Games, Networks, and Cascades."

• A supernetwork is a network consisting of nodes,links, and flows that operates over and above one or more existing networks. The Isenberg School of Management (University of Massachusetts, Amherst), under the direction of Anna Nugurney, maintains an interdisciplinary center called the Virtual Center for Supernetworks. The mission of the center is to foster the study and application of supernetworks and to serve as a resource to academia, industry, and government on transportation networks, logistical networks, telecommunications networks, and networks arising more generally in economic, environmental, financial and social settings. The home page of the center provides general information relating to supernetworks and describes various projects currently being supported by the center.

  The Visual Complexity Site provides an astonishing array of network visualizations created by complexity researchers. Types of visualized networks include art, business, computer systems, food webs, the Internet, knowledge networks, music, pattern recognition, political networks, social networks, transportation networks, and the World Wide Web.

Evolution

• Edge Foundation, Inc. was established in 1988 as an outgrowth of a group known as the Reality Club. The mandate of the Edge Foundation is to promote inquiry into, and discussion of, intellectual, philosophical, artistic, and literary issues, as well as to work for the intellectual and social achievement of society. The Edge World Question Center contains contributions from a variety of researchers whose work relates to complex systems and evolutionary modeling, such as Jared Diamond, J. Doyne Farmer, W. Daniel Hillis, Steven Pinker, Richard Dawkins, Rodney Brooks, Stephen Grossberg, Andy Clark, Freeman Dyson, Daniel Dennett, Stuart Kauffman, and Kevin Kelly, among many others.

• The Museum of Paleontology at the University of California at Berkeley maintains an on-line Museum of Paleontology Evolution Wing that permits visitors to explore exhibits and other resources related to the theory of evolution and the history of evolutionary thought.

• The MIT-sponsored political and literary forum Boston Review (BR) maintains an annotated list of pointers to articles on evolution that have appeared in BR since 1996. Past contributors include H. Allen Orr, Daniel Dennett, and Steven Pinker, among others. The most recent contribution (April/May 2000) is by John Alcock, titled "Misbehavior: How Stephen Jay Gould is Wrong About Evolution."

• From UMBC AgentNews (Volume 6, No. 8): The following multimedia (audio, video, text, images) lectures, among others, are hosted by boxmind.com. (Access requires Internet Explorer 4.x). Stephen Pinker lectures on language and the brain in a talk titled "The Ingredients of Language." John Searle lectures on consciousness in a presentation titled "Consciousness, Free Will, and the Brain." Richard Dawkins lectures on evolutionary biology in a talk titled "Survival of the Fittest - The Fittest What?." And Daniel Dennett lectures on consciousness in a lecture titled "Consciousness - More like Fame than Television." For more information, visit the Boxmind Company Website.

• A web site titled Evolutionary Theories in the Social Sciences is maintained by Johann Peter Murmann and Joe Fleischhacker at Northwestern University. Resources available at this web site include working papers, book announcements and reviews, journal announcements, conference information, and a discussion forum.

• John Catalano (New York, U.S.A.) maintains a web site titled The World of Richard Dawkins. Site resources include news items, books, writings, quotes, videos, software, biographical information, and links, all related to the work of Richard Dawkins. The site is "unofficial" in the sense that Richard Dawkins is not associated with it.

• A Repository of Articles on Evolution (with commentary and author replies) that have appeared in MIT's Boston Review (BR), a political and literary forum, is maintained online by BR. Authors of recent articles include Dennett, Orr, Berwick, Dawkins, Pinker, and Gould.

Complex Adaptive Systems

• The Complex Adaptive Systems Group at Iowa State University. This web site reports on general CAS research and teaching activities at ISU. It is maintained by Vasant Honavar, Computer Science Department, ISU.

• The Complex Adaptive Systems Seminar at Iowa State University. This web site provides general information about the weekly CAS Workshop at ISU, including time/place information, current and past workshop schedules, workshop participants, and CAS resource pointers. It is maintained by Leigh Tesfatsion, Department of Economics, ISU.

• The New England Complex Systems Institute (NECSI) is making available a new Complex Systems Web Guide that explains basic concepts, describes a variety of examples and applications, and illustrates various methods. The site will be expanded over the coming months.

• The complEX sYSTEms Network of exCEllence (EXYSTENCE) is supported by the Future Emerging Technologies unit of the European Commission. The aim of EXYSTENCE is to facilitate collaboration among European academic researchers and participants in business and industry who are interested in complex systems, from fundamental concepts to applications.

• The CSN Group is a self-organized network of people spanning various units at Indiana University-Bloomington, including informatics, cognitive science, physics, computer science, information science, and social science. The group is interested in the broad areas of complex systems, network science, modeling, simulation, artificial life, and visualization. The CSN Group site provides information about faculty and student participants, projects, news items, and course offerings.

• The Tree of Life is a multi-authored distributed Internet project containing information about the diversity of organisms on Earth, their history, and characteristics. The information is linked together in the form of the evolutionary tree that connects all organisms to each other. The project is coordinated by David R. Maddison and hosted by the College of Agriculture at the University of Arizona.

• The Bacterial Cybernetics Group Web Site at Tel Aviv University in Israel visually demonstrates how simple bacteria show unexpected sophistication when coping with adverse growth conditions. Citations and links to related papers and publications in Nature, Scientific American, and other outlets are also given. From the web site introduction: "`Simple' bacteria, coping with adverse growth conditions, show unexpected sophistication. When examined closely, this behavior is much more impressive. It seems as if the bacterial colony can not only compute better then the best parallel computers we have, but can also think and even be creative."

• Alexei Sharov (Research Scientist, Department of Entomoloy, Virginia Tech) maintains a web site on Biosemiotics. Biosemiotics is an interdisciplinary science that studies communication and signification in living systems. It considers communication as the essence of life. Resources provided at this site include pointers to introductory materials, on-line papers, researchers, organizations, and meetings.

• The Los Alamos National Laboratory maintains a web site titled Complex Systems Modeling that highlights the work of their Complex Systems Modeling Research Area group, led by Luis Rocha. Research areas include: adaptive agent simulation; adaptive computation; biocomputing; and social networks modeling.

• The Center for the Study of Complex Systems at the University of Michigan, a broadly interdisciplinary program designed to encourage and facilitate research and education in the general area of nonlinear, dynamical, and adaptive systems.

• The New England Complex Systems Institute (NECSI), established in 1997 by a group of faculty in the New England area, is an independent educational and research institution dedicated to advancing the study of complex systems.

• The mission of the Center for Connected Learning and Computer-Based Modelling (CCL) at Northwestern University, Evanston, Illinois is to create tools that will help learners (at all levels) to make greater sense of complex phenomena, and to study how learners come to understand complexity. In particular, a concrete goal of this center is to develop "object-based parallel modeling languages" (aka agent-based or multi-agent) that can be used by learners to create rich and detailed models of large systems of interacting agents and objects. The center maintains and updates the freely available modeling environments: NetLogo (multi-platform) and StarLogoT (available only for the Macintosh).

• David Wolpert and Kagan Tumer at the Computational Sciences Division (Nasa Ames Research Center, Moffett Field, California) maintain a web site describing their work on Collective Intelligence (COIN). A COIN is defined as a large multi-agent system for which two properties hold: (1) there is little to no centralized communication or control; and (2) there is provided a world utility function that rates the possible histories of the system. Applications to date include packet-routing, the leader-follower problem, and variants of W. Brian Arthur's El Farol bar problem. Other envisioned applications include routing of air traffic, control of swarms of spacecraft, and communication among the multiple processors in a modern computer.

• The Mobile Robots Group (MRG) at the Department of Artificial Intelligence at the University of Edinburgh in the United Kingdom. The MRG is a loose collection of staff and students who share the view that artificial intelligence will best be understood by using behaviour-based architectures to construct agents that live autonomously in the real world. Resources available at this site include research papers, course materials, robot descriptions, and related links.

• The Center for Complex Systems Research (CCSR) is an interdisciplinary group of faculty and graduate students investigating a variety of complex dynamic processes that occur in the areas of biology, physics, chemistry, and astonomy. The CCSR is located at the Beckman Institute for Advanced Science and Technology at the University of Illinois at Urbana-Champaign.

• The Center for Coordination Science is affiliated with the Sloan School of Management, MIT. Center projects can be roughly divided into three topic areas. Some center projects focus on how people currently work together, and how they might do so differently with new kinds of information technology. Other projects focus on developing new collaborative tools for such tasks as sharing information in groups, making group decisions, and managing projects. Finally, some projects focus on developing new theories of coordination that can help build better systems and help organizations coordinate themselves more effectively using such tools.

• Gary William Flake's The Computational Beauty of Nature: Computer Explorations of Fractals, Complex Systems, and Adaptation, was published in July 1998 by the MIT Press. A web site has now been established for this book on The Computational Beauty of Nature. The web site provides information about the book, source code for simulations involving fractals, chaos, complex systems, and adaption, and many additional resources for people interested in multidisciplinary topics involving computers, philosophy, and science.

• David E. Joyce (Professor of Mathematics and Computer Science, Clark University, Worcester, Massachusetts) maintains a gallery of pictures, all related to geometry and some related to chaos. Examples include Mandelbrot and Julia sets, kaleidoscopes, wallpaper groups, Bowditch patterns, roulettes, and hyperbolic tilings. The gallery can be accessed here.

• The Center for Polymer Studies (CPS) is a scientific visualization research center in the Physics Department and Science and Mathematics Education Center at Boston University. CPS is devoted to interdisciplinary research in aspects of polymer, random, and fractal systms and utilizes its expertise in these areas to develop experimental and computational materials for high school and undergraduate education. For more information, visit the CPS Web site.

• Kolmogorov complexity Website maintained by Ming Li and Paul Vitanyi of CWI (Centrum voor Wiskunde en Informatica) in the Netherlands.

• David Griffeath (Department of Mathematics at the University of Wisconsin, Madison, USA) maintains a website titled the Primordial Soup Kitchen. Griffeath specializes in the self-organization of random cellular automata. For the past ten years he has been producing colorful computer graphics and animations that illustrate the ability of local parallel update rules to generate spatial structure from disordered initial states, some of which have been featured in Nonlinear Science Today, The Scientific American, and James Gleick's Chaos: The Software. The Primordial Soup Kitchen provides a gallery for some of this work as well as providing links to relevant software for those interested in generating their own graphics and animations.

• Przemyslaw Prusinkiewicz, Mark Hammel, and Radomir Mech (Department of Computer Science, University of Calgary, Canada) maintain a hypertext document titled Visual Models of Morphogenesis: A Guided Tour. This document reviews models of morphogenesis with a significant visual component that have been developed or reproduced in the computer science departments at the University of Regina and the University of Calgary. Key topics include: morphogenesis; simulation and visualization of biological phenomena; developmental models; reaction-diffusion; diffusion-limited growth; cellular automaton; L-systems; and realistic image synthesis.

• The Visualization and Animation Group at the Institute of Computer Graphics and Algorithms, Vienna University of Technology, performs basic and applied research in computer graphics. Areas of focus include scientific visualization, virtual environments, and computer animation. In addition to research, the group specializes in consulting and technology transfer as well as computer graphics-related education at both the undergraduate and graduate levels.

• CeVis is a research center at the Department of Mathematics and Computer Science at the University of Bremen, Germany. CeVis stresses basic research in the areas of time series analysis, cellular automata, chaos, and fractals, and the related question of the visualization of these mathematical concepts. CeVis is also involved in teacher-enhancement activities in both the USA and Germany.

• The Society for Modeling and Simulation International is a nonprofit volunteer-driven corporation established in 1952. It is dedicated to advancing the use of modeling and simulation to solve real-world problems. The society publishes the journal Simulation as well as the Modelling and Simulation magazine.

Artificial Life and Artificial Intelligence

• A research group at the MIT Media Laboratory, led by Professor Rosalind Picard, maintains a website titled Affective Computing. Affective computing is defined as "computing that relates to, arises from, or deliberately influences emotion." The research highlighted at this site "focuses on creating personal computational systems endowed with the ability to sense, recognize, and understand human emotions, together with the skills to respond in an intelligent, sensitive, and respectful manner toward the user and his/her emotions."

• Andrew Hodges, author of Alan Turing: The Enigma, maintains a site devoted to the work of Alan Turing (1912-1954), titled the Alan Turing Home Page.

• An extensive list of announcements for past, current, and future events focusing on artificial life and related fields, with a searchable database, can be accessed at a website titled Artificial Intelligence: Forthcoming Events.

• Thomas S. Ray (ATR Human Information Processing Laboratories, Kyoto, Japan) has an interesting online introduction to Artificial Life. From the abstract: "Artificial Life (AL) extends the field of biology by allowing us to study living forms other than those occurring naturally on Earth. In this way, AL bears the same relationship to biology that synthetic chemistry does to chemistry. Some of the most significant advances in AL have been in the area of synthetic evolutions within computers. One of the major currents in this work has been to move towards systems which evolve freely within the digital medium, like the evolution by natural selection in the carbon medium that generated life on Earth. The primary objective of this work is to provoke digital evolution to generate complexity within the digital medium, comparable in magnitude to the complexity of organic life."

• Prof. Dr. R. Pfeifer and Hanspeter Kunz (Institut fur Informatik, Uni Irchel) have written a comprehensive illustrated monograph titled Artificial Life that is particularly suitable for teaching purposes. Coverage includes pattern formation, distributed intelligence, agent-based simulations, and artificial evolution. All seven chapters of this book (in pdf format) can be downloaded free of charge.

• Ariel Dolan, a freelance software developer from Ramat-Gan, Israel, has made available an Artificial Life Database. This is a searchable database of alife-related sites on the net gathered automatically gathered by an intelligent search bot. From his announcement: "The new Alife Database is a successor to the first Alife Database. Unlike the first version, it is not specifically oriented towards online experimentation and code sharing. It is a much larger and more comprehensive database, where the data is automatically gathered by an intelligent search bot that scans the world wide web for Alife related pages. Since the gathering process is automatic, it is inevitable that a certain percentage of the records will turn out to be irrelevant. However, the searching capabilities of the database should make it easy to filter the displayed data."

• The Artificial Life Models of Flocking Behavior site maintained by Craig Reynolds, famous for his "boids," contains extensive references and pointers to work related to group motion in animals.

• Artificial Life Online, an alife web site descended from the site once maintained by the Santa Fe Institute. See also the SFI home page for other related materials.

• Artificial Life Pages at Yahoo.

• Moshe Sipper (Ben-Gurion University, Israel, and the Logic Systems Library, EPFL, Switzerland) maintains a Website titled Artificial Self-Replication Page. The main motivation of the site is a desire to understand the fundamental information-processing principles and algorithms involved in self-replication, independent of their specific physical realization. The site summarizes research on self-replicating systems arranged in chronological order. Each system is described by title, author(s), year, model, implementation, and a short description.

• Charles Ofria (California Institute of Technology, Pasadena, CA) maintains a web site for the Avida Group. From the web site: "The avida group is studying the processes which make living systems appear `alive.' Fundamentally, this research is guided by the principle that a certain universality underlies these processes, and that they can be implemented in different media as long as they allow for enough complexity. Thus, the topics we research include evolution, co-evolution, adaptation, ecology, etc., for the simplest of living systems. In particular, we study populations of self-replicating computer programs adapting to a complex fitness landscape as a substitute for carbon-based adapting populations, as the former are much easier to control. The avida software, which controls the artificial habitat for self-replicating code, was inspired by (Tom) Ray's tierra."

• Complexity and Artificial Life Research website, maintained by the non-profit organization CalResCo, dedicated to the promotion of the Complexity System Sciences.

• Biota.org, a special interest group of the Contact Consortium (a not-for-profit membership and research organization based in Scotts Valley, California), hosts a website maintained by Karl Sims titled Evolving Virtual Creatures. Sims' famous creatures evolve their morphology (body structure) over time in an attempt to accomplish various set tasks. Visitors to this site can view stills of these creatures in competition and in locomotion at successive evolutionary time steps. Instructions for obtaining the original MPEG movie of Sims' creatures in motion are also given. See, also, Karl Sim's Home Page.

• Mitchel Resnick and Brian Silverman (Epistemology and Learning Group, MIT Media Laboratory) maintain an "active essay" titled Exploring Emergence that explores the idea of emergence of global regularities arising from simple interactions. Visitors with a Java-enabled browser can activate animations that illustrate the concepts under discussion.

• From the Framsticks home page maintained by Maciej Komosinski and Szymon Ulatowski (Institute of Computer Science, Poznan University of Technology): "Framsticks is a three-dimensional life simulation project. Both physical structure of creatures and their control systems are evolved. Evolutionary algorithms are used with selection, crossovers, and mutations. Finite elements method is used for simulation. Both spontaneous and directed evolutions are possible."

• The Oz Project Archive maintained at Carnegie Mellon University reports on a now-inactive project whose objective was to develop technology and art to help artists create high quality interactive drama based in part on artificial intelligence technologies. A key objective was to build believable agents in dramatically interesting micro-worlds.

• Since 1987, Will Wright (inventor of SimCity) and his colleagues at Maxis have developed more than a dozen computer simulation games, many related to architecture and city planning. Wright's newest release is the Sims, an elaborate Tamagotchi-style neighborhood that allows players to freely manipulate their virtual inhabitants. For more information about the Sims, visit the Sims Website.

• The extensive artificial life resources depository Zooland maintained by Jörg Heitkötter, provides pointers to an extensive catalogued collection of resources on artificial life. Topics covered include computer viruses, artificial life simulators, infospiders, biomorphs, L-systems, cellular automata, and much more.

• The American Association for Artificial Intelligence (AAAI) maintains a website titled Welcome to AI Topics "for students, teachers, journalists, and everyone who would like to explore what artificial intelligence is and what AI scientists do." The stated goal of this extensive and meticulously organized site is to offer a limited number of exemplary non-technical resources catagorized and annotated to provide meaningful access to basic information about AI. Social science research using AI tools can be found at the following successive links starting from the the Site Map: Agents -> Multi-Agent Systems -> Related Pages -> Social Science.

• The U.S. Navy Center for Applied Research in Artificial Intelligence maintains a web site of AI and Alife-Related Materials.

• UMBC AgentWeb is a web site featuring extensive information and resources about intelligent information agents, software agents, softbots, knowbots, infobots, etc. Maintained at the University of Maryland Baltimore County (UMBC) Lab for Advanced Information Technology by Tim Finin.

Learning and Human Cognition

• The Agents Learning About Agents web site is dedicated to the study of what happens when agents (i.e., pro-active, goal-driven, selfish, independent software/hardware constructs) start to learn about each other, especially if they do so in order to gain a competitive advantage over other agents. Resources available at this site include pointers to classes, laboratories, and other web sites useful for this topic area.

• The Autonomous Learning Laboratory (ALL), co-directed by Andrew G. Barto and Sridhar Mahadevan, carries out foundational interdisciplinary research on machine learning and computational models of biological learning. Autonomous learning refers to what a self-reliant agent must do to learn from its own experiences. The long-term goals of the laboratory are to develop more capable artificial agents, to improve our understanding of biological learning and its neural basis, and to forge stronger links between studies of learning by computer scientists, engineers, neuroscientists, and psychologists. Areas of interest include reinforcement learning, machine learning, abstraction, hierarchy, motor control, robotics, computational neuroscience and developmental psychology.

• Randall Whitaker (Logicon Technical Services, Inc., Wright-Patterson AFB, Ohio) maintains a site titled Self-Organization, Autopoiesis, and Enterprises. Included at the site is a link to a tutorial on autopoeisis, described as follows: "This introductory tutorial is designed to give you a brief overview of autopoietic theory -- the term I use to denote the work of Chilean biologists Humberto R. Maturana and Francisco J. Varela. ... Maturana's early work in neurophysiology and perception ... led him to question the information-theoretic notions of cognition. (H)e subsequently created and refined (his theory) with Varela. ... As a biological phenomenon, cognition is viewed with respect to the organism(s) whose conduct realizes that phenomenon. In autopoietic theory, cognition is a consequence of circularity and complexity in the form of any system whose behavior includes maintenance of that selfsame form. This shifts the focus from discernment of active agencies and replicable actions through which a given process (`cognition') is conducted (the viewpoint of cognitive science) to the discernment of those features of an organism's form which determine its engagement with its milieu."

• The goal of BotSpot is to be a definitive resource for bots, intelligent agents, and artificial intelligence on the web. The site includes: fourteen searchable Bot Classification Databases for bot implementations; FAQs; book recommendations; and pointers to articles, electronic journals, upcoming conferences, previous conference proceedings, and language and code for creating bots and intelligent agents. The site also supports a free monthly BotSpot Newsletter. BotSpot has received over 150 awards in its first twelve months of operation, including a designation by PC Magazine as one of their top 100 recommended web sites.

• The Center for Adaptive Behavior and Cognition (ABC) is directed by Prof.Dr. Gerd Gigerenzer (Max Planck Institute, Berlin), one of the most well-known and articulate critics of the model of the perfectly rational human being claimed to be implicit in the work of Nobel laureate Daniel Kahneman, Amos Tversky, and other researchers investigating perceived anomalies in experimentally observed human decision making under uncertainty. ABC researchers focus on the discovery and study of simple cognitive satisficing algorithms that people use to solve adaptive problems in specific real-world domains, such as avoiding dangers, choosing mates, and investing in offspring. ABC takes an evolutionarily-inspired view of the mind as a collection of these task-specific algorithms and modules rather than as a general-purpose problem solver.

• The Center for Research on Concepts and Cognition (CRCC) at Indiana University is an interdisciplinary center for research in cognitive science directed by Douglas Hofstadter. CRCC research focuses mainly on emergent computational models of creative analogical thinking and its subcognitive substrate -- namely, fluid concepts. The group also conducts research (mostly non-computational) in a number of other areas of cognitive science, including error-making, creative translation, scientific discovery, musical composition, the comprehension and invention of jokes, the nature of sexist language and default imagery, philosophy of mind, and foundations of artificial intelligence.

• The CogWeb Site maintained by Francis Steen (Communication Studies, UCLA, Los Angeles) is devoted to exploring the relevance of the study of human cognition to literary and cultural studies. Resources available at the site include pointers to related sites and articles as well as to bibliographic materials on linguistics, cognitive science, evolution and cognition, and cognitive cultural studies (both early and modern).

• Stan Franklin, Professor of Mathematical Sciences at the University of Memphis, Tennessee, and well-known author of Artificial Minds (MIT Press, 1995), maintains a web site on Conscious Software. From the web site introduction: "By a `conscious' software agent we mean a cognitive agent (an autonomous agent with human-like cognitive features) designed within the constraints of Baar's global workspace theory of consciousness. Like the Roman god Janus, the conscious software project has two faces, its science face and its engineering face. Its science side will flesh out the global workspace theory of consciousness, while its engineering side explores architectural designs for information agents that promise more flexible, more human-like intelligence within their domains." Accounts of various conscious software projects by Franklin and his collaborators can be found at the Conscious Software web site.

• Adrian Thompson (COGS, University of Sussex, UK) maintains a web site titled Evolutionary Electronics Web Links. This site provides pointers to researchers and research groups around the world specializing in evolvable hardware.

• A repository of resources on the use of artificial intelligence (AI) in the design of games can be found at the Game AI Page. This site stresses practical approaches to the problem of building better computer opponents and is aimed at both game developers and game players.

• The Laboratory for Natural and Simulated Cognition (LNSC) at McGill University in Montreal, Canada, investigates human cognition through a combination of psychological and computational approaches. Basic psychological phenomena are simulated in a connectionist framework, often leading to predictions that are tested with humans. Current projects concern cognitive development, interactions between knowledge and learning, techniques for analyzing knowledge representations in neural nets, and cognitive consistency phenomena in social psychology.

• L. Tesfatsion (Economics, Iowa State University, Ames, IA) maintains a website title Learning and the Embodied Mind. Resources at this website include annotated pointers to tutorials, general readings, software, research groups, and individual researchers.

• L. Tesfatsion (Economics, Iowa State University, Ames, IA) maintains a website title Learning Via Criterion Filtering. Criterion filtering is the direct updating of criterion functions on the basis of transitional reward assessments in analogy to Bayes' Rule for the updating of probability distributions on the basis of transitional probability assessments.

• MIT CogNet is an electronic community for the cognitive and brain sciences under development by the MIT Press. The intention is to bring together current and classic resources in the field and provide a unique, interactive forum for scholars, students, and professionals. Services will include: a searchable full-text library with a growing collection of books, journals, and other reference works; an academic almanac of cognitive science programs; editorials on groundbreaking or controversial research; job listings; virtual poster sessions; threaded discussion groups; and community member profiles. MIT CogNet is a free service through August 31, 2000, and is actively seeking charter members.

• The goal of the MIT Robust Open-Agent Systems (ROMA) Research Group is to learn how to develop multi-agent systems for open contexts where the constituent agents can come from anywhere, may be buggy or even malicious, and must run in the dynamic and potentially failure-prone environments at hand. This is viewed as an important area of research since many emerging problems (e.g., electronic commerce, large product development projects, multi-national rescue operations) require the ability to rapidly assemble virtual organizations on the Internet with partners who may have never worked together before.

• The Perceptual Science Laboratory at the University of California, Santa Cruz, California, is engaged in a variety of experimental and theoretical inquiries in perception and cognition. A major research area concerns speech perception by ear and eye, and facial animation. Laboratory researchers have also tested a general fuzzy logical model of perception in a variety of domains, including perception and understanding of language, memory, object, shape, depth perception, learning, and decision making. Information about the Perceptual Science Laboratory available at the laboratory web site includes research reports and data.

• From UMBC AgentNews (v6n9): A free on-line dictionary of topics relating to the philosophy of mind, edited by Chris Eliasmith (Washington University, St. Louis), can be accessed at the Philosophy of Mind Home Page. See, also, the Stanford Encyclopedia of Philosophy Web Site edited by Edward N. Zalta (Stanford University). The latter site is a dynamic encyclopedia of entries for all areas of philosophy, including many entries relevant to agents, cognitive science and AI.

• The Autonomous Agents Laboratory at Michigan State University maintains an online repository of resources on Reinforcement Learning (RL). The website provides resources on both RL research and applications to areas such as robotics and industrial problems. Resources available include technical publications, sample testbeds, implementations of various algorithms, online simulation packages, workshop information, and discussion forums for a variety of research areas within RL. The website is supported by the National Science Foundation.

• The Social Psychology Network is an extensive database on social psychology maintained by Scott Plous (Weslyan University) and supported by the National Science Foundation. The database provides more than 5,000 links to psychology-related resources. The database can be searched by topic or keyword.

• The Tangible Media Group at the MIT Media Laboratory (Cambridge, Massachusetts), founded and directed by Hiroshi Ishii, focuses on the design of seamless interfaces between humans, digital information, and physical environments. From Hiroshi Ishii: "People have developed sophisticated skills for sensing and manipulating our physical environments. However, most of these skills are not employed by traditional Graphical User Interface (GUI). Tangible Bits, our vision of Human Computer Interaction, seeks to build upon these skills by giving physical form to digital information, seamlessly coupling the dual worlds of bits and atoms. Guided by the Tangible Bits vision, we are designing `tangible user interfaces' which employ physical objects, surfaces, and spaces as tangible embodiments of digital information. These involve foreground interactions with graspable objects and augmented surfaces, exploiting the human senses of touch and kinesthesia. We are also exploring background information displays which use `ambient media' ---- ambient light, sound, airflow, and water movement. Here, we seek to communicate digitally-mediated senses of activity and presence at the periphery of human awareness. Our goal is to realize seamless interfaces between humans, digital information, and the physical environment taking advantage of the richness of multimodal human senses and skills developed through our lifetime of interaction with the physical world."

Evolutionary Computation

• The Adaptive Computation Group (Computer Science Department, University of New Mexico) maintains a web site on Adaptive Computation.

• Jaime Fernandez (Houston, Texas) maintains the Genetic Programming Notebook, a website on genetic programming and related topics.

• Memetic algorithms are population-based methods for heuristic search in optimization problems that combine local search heuristics with crossover operators. [Other names that have been used for these types of methods include hybrid genetic algorithms, parallel genetic algorithms, and genetic local search.] The purpose of the Memetic Algorithm Home Page, maintained by Pablo Moscato (moscato@densis.fee.unicamp.br), is to provide a central location where pointers to information about memetic algorithms can be found and where researchers pursuing related methodologies can become acquainted with each other's work. Resources available at this site include: conference information; a list of pointers to researchers working on issues related to memetic algorithms; and bibliographies on memetic algorithms, population memetics, and cultural evolution that include numerous downloadable papers.

• Pablo Moscato (Universidade Estadual de Campinas, Brazil) maintains a Memetic Algorithm Bibliography. He characterizes "memetic algorithms" (which he also refers to as "hybrid genetic algorithms") as a population-based approach for heuristic search in optimization problems that combines local search heuristics with crossover operations. The 338 items currently in the bibliography can be searched by query using a number of different options.

• The website maintained by the IEEE Neural Net Council provides extensive information on research, conferences, and other materials relating to artificial neural networks.

• Dr. K. Gurney (University of Sheffield, U.K) maintains a set of introductory notes on artificial neural networks suitable for student use.

• The Fractint L-Systems Tutorial site maintained by Noel Giffin (University of British Columbia, Canada) provides a tutorial by William McWorter on L-systems that makes use of the program Fractint for fractal generation on IBM-compatible personal computers. Topics include: an introduction to L-systems; plants; tilings; space-filling curves; true fractals; variations; and additional information. A link to the Fractint home page is also provided.

• Pablo Moscato (Campinas, SP, Brazil) maintains a website devoted to the Traveling Salesman Problem (TSP) titled the Traveling Salesman Problem Bibliograghy (TSPBIB) Home Page. Resources provided at this site include a listing of TSP-related papers, source code, and links.

Demos, Software, and Software Development

• A separate resource site devoted to interactive demos is now maintained by Leigh Tesfatsion (Economics, Iowa State University), titled ACE/CAS Comp Labs and Demonstration Software.

• A separate resource site devoted to software and software development is now maintained by Leigh Tesfatsion (Economics, Iowa State University), titled ACE/CAS General Software and Toolkits

• Floating Point Arithmetic and Agent-Based Models
  When doing arithmetic on a computer, the uncountably infinite set of real numbers must somehow be squeezed into a discrete set of isolated numbers represented in binary floating-point format. The resulting floating-point errors can lead to some unpleasant surprises for the unwary. For example, floating-point addition does not obey the associative law, e.g., (0.1 + 0.2) + 0.3 can fail to equal 0.1 + (0.2 + 0.3). Moreover, summing 0.05 twenty times can yield a total that differs from 1. In both cases the problem can be traced to the fact that simple-looking base-10 numbers such as 0.1 are not exactly representable in binary floating-point format because they correspond to infinitely repeating binary numbers.
  Researchers at the Macaulay Land Use Research Institute (MLURI) in Aberdeen, Scotland, have been conducting a number of important and interesting studies to investigate the effects of floating-point errors in agent-based models implemented in FEARLUS. A summary of these efforts, with pointers to related papers and demos, can be accessed here. See, in particular, a January 2005 JASSS paper by three MLURI researchers, Gary Polhill, Luis R. Izquierdo, and Nicholas M. Gotts, titled "The Ghost in the Machine (and Other Effects of Floating Point Arithmetic". This paper investigates the effects of floating-point errors in a model of land use change and in the Santa Fe Artificial Stock Market model.
  Based on their work to date, the MLURI researchers conclude that floating-point errors are not likely to be of major importance if a model does not perform many operations and if it does not contain branching statements. However, on a personal note, I would like to warn about the need to be careful also about imported utilities such as pseudo-random number generators. In my ISU electricity research group we have just discovered that a major java source file (EmpiricalWalker.java) in the well-known and frequently imported cern.jet.random package is disastrously susceptible to floating-point addition errors.

Commercial Development and Application

• Parasitic computing is an example of an Internet technology that has potential both for great good and for serious harm. Internet protocols guaranteeing reliability can be exploited to perform computations on behalf of a remote node without express permission. For example, a remote machine can force targeted computers to solve a piece of a complex computational problem merely by engaging them in standard communications, thus harnessing together tremendous computational power. Vincent Freeh, Albert-Laszlo Barabasi, and Jay Brockman (University of Notre Dame, Indiana) and Hawoong Jong (Korean Advanced Institute of Science and Technology, Taejon) maintain a Parasitic Computing Website whose purpose is to raise awareness of the ethical, legal, and scientific ramifications surrounding this new technology.

• Rajkumar Buyya (University of Melbourne, Australia) maintains a website titled the Grid Computing Info Centre (GRID Infoware). The purpose of the site is to contribute to the development and advancement of technologies that enable the access to computing power and resources with the same ease as the access to electrical power. Resources available at the GRID home page include software, discussion papers, and news items devoted to this topic.

• EnterTheGrid, supported by Primeur, is a guide and news source regarding resources on grid computing (distributed computing, peer-to-peer computing, and parallel computing). Features include recent news items, news articles, company profiles, and a research repository.

• Supported by the Network Cybernetics Corporation (Dallas, Texas), the Robots.Net Site provides current news on personal and industrial robotics, robot competitions, and a variety of other robot-related events.

• In collaboration with others, Robert Bernard and other researchers at PricewaterhouseCoopers Consulting have worked to develop software called CommunityViz as an aid for community planning. This software was featured in an article titled "SimCity, Real Life" in Newsweek (August 5, 2002). The core forecasting component of CommunityViz, called the Policy Simulator, is an agent-based model to be tailored to the specifications of whatever community is under study. A White Paper describing the Policy Simulator is available at the CommunityViz Home Page.

• A web site titled Enabling Virtual Business is maintained by Ontology.Org. Resources available at this web site include press releases and other news items, related web sites, articles, and event announcements.

• Filippo Menczer (School of Informatics and Computer Science Department, Indiana University) organized a Fall 1999 seminar series on Complex Adaptive Systems and Their Business Applications at the University of Iowa, sponsored by the Santa Fe Institute. Interested readers can access a detailed report on this seminar series, including speakers, topic abstracts, powerpoint presentations, and downloadable papers and related resources, at the above seminar report site.

• The UMBC Institute for Global Electronic Commerce maintains an extensive e-commerce directory (ecTechWeb) of news, information, and Internet resources for both product developers and academic researchers.

• The Artificial Intelligence Applications Institute (School of Informatics, University of Edinburgh) was established in 1984 to encourage the development and use of artificial intelligence methods in practical applications.

• Researchers participating in the Agents Technology Group at Hewlett Packard Laboratories are exploring the use of software agents in electronic commerce. As preliminary steps, they are developing their own agent toolkit called Woad and working on a formal analysis of the efficiency of various mult-agent systems architectures.

• From Tim Finin (UMBC): "Respond.com, a startup focused on `demand driven' auctions and markets, launched its services in mid-July. Like other companies exploring the space of `reverse auctions', e.g., eWanted and Accompany, it supports buyers looking for sellers. Respond's approach is based on a simple model which connects buyers and sellers via (initially anonymous) email. Respond.com says `We're targeting three broad groups: smaller offline businesses that don't have or can't afford their own web sites, e-commerce startups that aren't capitalized and larger vendors that want to reach buyers coming to our site.'" For more information, visit the Respond.com Website, the eWanted Website, and/or the Accompany.com Website. [Note 5/22/03: The Accompany.com site appears to have a possibly temporary infinite loop problem preventing stable access.]

• The Agent-Based Engineering (ABE) Research Group at Stanford University's Center for Design Research strives to bring a practical, application-oriented approach to agent technology, in addition to making theoretical in-roads into this field. The majority of the work carried out by this group is focussed on applying agent-based technology to the engineering design process -- design decision support, concurrent engineering and collaborative design. Additional information about this group can be obtained at the ABE web site.

• The St. Petersburg Central Research Design Institute for Robotics and Technical Cybernetics specializes in research on robotics, photo technics, control and monitoring systems, laser technologies, information systems and computer networks, telematics, and LAN manufacturing.

• Peter Fingar (Executive Partner, Greystone Group, Tampa, Florida) maintains the Essential Library for the Digital Economy. This site provides reviews of business and technology books related to e-commerce, e-business, the "New Economy," and web technology. It also provides links to articles, reports, and other web sites that focus on these topics.

• The Electronic Commercial Agents (ElComAg) Project at the Norwegian University of Science and Technology (Trondheim, Norway) involves the design of facilities for the trading of knowledge through electronic commerce. Topics include: (1) conceptual modeling of knowledge and trading process; (2) the design of sale-sites (electronic marketplaces); (3) the design of agents for serving the trade process; and (4) information system architecture for knowledge trade.

• Cybion Corporation (Boulogne, France) maintains a virtual community called Agentland populated by artificially intelligent software agents. Agentland is essentially a shopping mall where interested viewers can browse for personal assistants of all types in situ. Agentland showcases a selection of agents from both established software companies and independent developers.

• The Alliance for Innovative Manufacturing (AIM) at Stanford University maintains a site titled How Everyday Things Are Made. The site provides virtual factory tours covering the manufacturing processes for over forty types of common products (cars, planes, chocolate, glass bottles, etc.). These videos stress the extraordinary degree of coordination among input suppliers, producers, and distributors required to bring to market even seemingly simple products such as a jelly bean.

Miscellaneous Sites

• The constructive approach to mathematics is enjoying a resurgence among mathematicians, due in large part to the growing power of computers. The Stanford Encylopedia of Philosophy provides an extended 20-page discussion of constructive mathematics that might be of interest to agent-based computational modelers.
  As explained in this encylopedia entry, constructive mathematics is distinguished from its classical mathematical counterpart by its strict interpretation of the phrase "there exists" to mean "one can construct." For example, consider the statement "there exists an object x with property P." For a constructive mathematician, a proof of this statement requires that an algorithm be exhibited that constructs x and demonstrates, by whatever calculations are necessary, that x has property P. In contrast, for a classical mathematician, the proof of this statement could also be established by a "proof by contradiction," i.e., a demonstration that the negation of the statement induces a contradiction of something known (or assumed) to be true, with no actual construction of x.

  Roland Gunesch (Mathematics, Penn State University) maintains a web site on Entropy. The goal of this web site, as conceived by its original developer Chris Hillman (Ph.D. in Mathematics, University of Washington), is to promote appreciation, understanding, and applications of entropy. Resources include a brief overview of entropy as well as pointers to journals, conferences, research groups, software, expository articles, textbooks, and suggested readings in a variety of specific disciplines.

  Jay Scott (The Math Forum, Swarthmore, Pennsylvania) maintains a web site on Game-Playing Computers for artificial intelligence researchers and game programmers. The main focus is on how computers can learn to get better at playing games. The site provides descriptions for a variety of game-playing programs that rely on heuristic search algorithms, neural networks, genetic algorithms, temporal differences, and other methods, including programs for robotic soccer, backgammon, pursuit-evasion games, and chess. In addition, the site provides pointers to tutorials, individual researchers, and related web sites.

  Adam Smith (1723-1790) was a Scottish political economist and philosopher whose most famous work (The Wealth of Nations, 1776) laid the foundations for laissez-faire (free-market) economic theory. In this work he coined the term "invisible hand" for a situation in which economic traders, pursuing only their own self interest, nevertheless manage to self-organize in ways of benefit to society as a whole. Robin Chew (Lucid Interactive) has developed a Web site devoted to the Legacy of Adam Smith. Among other things, the site provides e-book access to several of Adam Smith's works in their entirety (e.g., The Theory of Moral Sentiment and The Wealth of Nations).

  The OpenABM Consortium is a group of researchers, educators, and professionals with a common goal -- improving the way agent-based models are developed, shared, and utilized. The organizers are currently developing a model archive to preserve and maintain digital artifacts and source code comprising an agent-based model. Developers are encouraged to add their models to the model archive (prior member registration required).

  The Object-Field Blog is maintained by Vlasios Voudouris. The main aim of the blog is to encourage and promote discussions around the "object-field model" as a way of representing indeterminate phenomena and reasoning about them. In particular, this blog promotes discussions about agent-based computational economics, GIS (geographic information systems) modeling, evolutionary economics, applied statistics andmathematics, visualization, and the theory of decision making.

  Random.Org offers "True Random Numbers" to anyone on the Internet. The numbers are generated using atmospheric noise from a radio. All generated numbers are tested statistically and the results posted in real-time mode. The site is maintained by Mads Haahr (Computer Science, University of Dublin, Tinity College, Ireland).

  The Through Mazes to Mathematics site, maintained by Tony Phillips (Mathematics Department, SUNY Stony Brook), uses maze illustrations and hands-on maze exercises as a way of enhancing interest among students in basic mathematical principles.

  The World of Escher, Inc. (Cordon Art B.V., The Netherlands), maintains an informational and commercial website devoted to the Work of M. C. Escher (1898-1973), a Dutch graphic artist most recognized for his depictions of spatial illusions, impossible buildings, and intricate repeating geometric patterns (tessellations).

  Zipf's Law, named after the Harvard linguist professor George Kingsley Zipf (1902-195), states that the frequency of occurrence of some event E, as a function E(R) of it's rank R as determined by this frequency of occurrence, takes the form of a power law E = E(R) = 1/R^k,
  where the exponent k is close to unity. Wentian Li (North Shore LIJ Research Institute for Medical Research) maintains a website titled Zipf's Law that provides archival access to numerous works related to Zipf's Law.

Copyright © 2010 Leigh Tesfatsion. All Rights Reserved.