Research Sites and Groups
Agent-Based Computational Economics
and Complex Adaptive Systems

- Last Updated: 8 January 2021
- Site Maintained By:
-
Leigh Tesfatsion
- Research Professor & Professor Emerita of Economics
- Courtesy Research Professor of
Electrical & Computer Engineering
- Heady Hall 260
- Iowa State University
- Ames, Iowa 50011-1054
- http://www2.econ.iastate.edu/tesfatsi/
tesfatsi AT iastate.edu
- Agent-Based Computational Economics (ACE) Website:
-
http://www2.econ.iastate.edu/tesfatsi/ace.htm
Support for New Economic Thinking
- The
Academy of Science and Engineering (ASE)
is a non-profit organization dedicated to advancing science and engineering innovation and excellence for the benefit of humanity. The ASE website features groundbreaking literature, conference updates and news releases. The intent of the ASE it to provide a vital, internationally recognized hub for scientifically-involved professionals, students, and other interested parties. Core areas of interest include Economic Computing (under the ASE Science Division) and Computational Social Science (under the ASE Humanity Division).
-
Complexity Research Initiative for Systematic Instabilities (CRISIS)
is a consortium of universities, private firms and policymakers that aims to build a new model of the economy and financial system that is based on how people and institutions actually behave. It was set up in the wake of the global financial crisis that showed that existing models that had been adequate for the good times were utterly inadequate for predicting major crises.
-
The Enlightened Economist
is a blog by Diane Coyle, OBE, reporting on economics and business books that support new economic thinking, with a special focus on the economic and social effects of new technologies.
- The
European Association for Evolutionary Political Economy (EAEPE)
is an active scholarly association in the area of institutional and evolutionary economics broadly conceived. The Association has developed into a pluralistic forum with room for a variety of approaches. One of the research areas supported by the EAEPE
at its annual conferences through designated sessions is
Evolutionary Economic Simulations (EES).
-
From Human-Subject Experiments to Computational-Agent Experiments (and Everything in Between)
- The
German Network for New Economic Dynamics (GENED)
was organized in September 2013 to foster exchange and discussion among researchers, in particular doctoral students, who are interested in heterogeneous agent modeling.
- The
Institute for New Economic Thinking (INET)
was created to broaden and accelerate the development of new economic thinking that can lead to solutions for the great challenges of the 21st century. The havoc wrought by our recent global financial crisis has vividly demonstrated the deficiencies in our outdated current economic theories, and shown the need for new economic thinking - right now.
INET is supporting this fundamental shift in economic thinking through research funding, community building, and spreading the word about the need for change. We already are a global community of thousands of new economic thinkers, ranging from Nobel Prize winning economists to teachers and students who have emerged out from the shadows of prevailing economic thought, attracted by the promise of a free and open economic discourse.
- The aim of the
International Joseph A. Schumpeter Society (ISS),
founded in 1986, is the scientific study of the problems of development, particularly in advanced economies. Development is perceived as a combination of growth and structural change, broadly defined. The ISS is open to research by scholars of all scholarly traditions provided the research is scientifically sound and non-ideological; that is, provided it respects facts as they are rather than facts as one wishes them to be. The
Journal of Evolutionary Economics,
founded in 1991, has been the affiliated journal of the ISS since 1993.
- Under the direction of Roger Guesnerie (Collége de France, Paris), a group of critics of the Rational Expectations Hypothesis (REH), notably in the study of financial markets and macroeconomies, has come together to organize the
International Network on Expectational Coordination
(INEXC).
The first objective of the INEXC is to provide support for the dissemination of knowledge through conferences, workshops, and exchanges of visitors. The second objective is to attract and support the work of younger colleagues who wish to pursue alternative approaches to expectational coordination issues, particularly high-risk high-expected return approaches. A more detailed description of purpose for INEXC can be found
here.
- The
Modelling Social Systems
discussion group at the University of Southampton (UK) consists of researchers with a common interest in using agent-based simulations (and other forms of computational and mathematical modelling) to look at the social world. Of particular interest is the
Listing of ABM Resources
consisting of materials on agent-based modeling that discussion group members have highlighted as having been particularly influential in encouraging their interest.
- The
Network for Computational Modeling
for SocioEcological Science (CoMSES Net)
is a scientific research coordination network to support and expand the development and use of computational modeling in the social and life sciences.
OpenABM
is a node in the CoMSES Network, providing a growing collection of tutorials and FAQs on agent-based modeling, a model library intended to provide a locus for authors and modelers to share their models, and forums for modeling-related discussions and job postings.
- The
Non-Equilibrium Social Science (NESS) Group
was created during 2010/2011. A key focus of NESS is economics, where the equilibrium approach (though dominant) struggles to capture the economic realities observed in the world today. However, the aim is to establish a network of leading scholars and practioners from all social science disciplines to make real progress in understanding complex social and economic systems.
-
Rethinking Economics
is an international network of economics students, thinkers and citizens, including those with no previous training in economics, who are organising to create fresh economic narratives to challenge and enrich the predominant neoclassical narrative. The professed aim of the network is "to demystify and diversify economics in the public eye; to educate ourselves and other students in a more reflective economics; to inspire divergent economists to engage with one another in debate; and to promote a politics of responsibility with academic economists." Additional organizers and collaborators are actively being sought.
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.
- 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
Agent-Mediated Electronic Marketplaces Lab (AMEM),
under the direction of Tuomas Sandholm (Carnegie Mellon University),
studies how computers impact traditional game theory. This involves everything from large-scale equilibrium computation to automated negotiation to the design of new economic structures such as markets.
- Nicholas Gessler (Duke University, NC)
maintains an interesting unusual website titled
Alice: Artificial Life, Culture,
and Evolution.
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.
-
The
Artificial Intelligence Economic Research Center (AI-ECON)
was established in 1995 at the College of Social Sciences, National Chengchi University. The goal of the center is to fully harness computer power to facilitate the integration of economics into a multidisciplinary research stream permitting cross-fertilization of ideas.
- 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.
- 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
Cognitive 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.
- Professor Charles A. Holt (Department of Economics, University of
Virginia) maintains a "Y2K Bibliography" on
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.
- Peer-Olaf Siefers (University of Nottingham, UK) is the organizer of a Special Interest Group (SIG) called the
Behavioural Economics Meets object oriented Simulation SIG (BEMooSSIG).
The BEMooSSIG is a discussion forum for people interested in studying how to use games (lab experiments) as a data collection tool or as a mechanism to inform/support modeling the decision making of actors in object oriented social or socio-technical system simulation models and how the simulation results can be used to cross-validate game results.
- 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.
- Prof. Dr. Ernst Fehr (University of Zurich) directs the Research Priority Program on the
Foundations of Human Social Behavior.
Participants in this interdisciplinary program combine insights from modern economic theory with results from neuroscience, social psychology, philosophy, and evolutionary anthropology 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.
- Al Roth (Stanford University) maintains an extensive informative web
site on
Game Theory and Experimental Economics.
- 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.
- Ariel Rubinstein and Eli Zvuluny (School of Economics, Tel Aviv
University, and Princeton University, New Jersey) maintain a website on
Game Theory: Didactic Web-Based Experiments.
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."
- David K. Levine (UCLA) maintains a list of web resources that includes
Game Theory Links.
- Robert Goldstone, 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.
- Carl T. Bergstrom (Department of Zoology, University of Washington,
Seattle) maintains a website on
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.
- 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
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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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
Center for Imperfect Knowledge Economics
at the University of Copenhagen is sponsored by the Institute for New Economic Thinking(INET).
- The
IKE Group (Aalborg)
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.
- 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 site titled
Formation of Economic and Social Networks
is maintained by Leigh Tesfatsion (Economics, Iowa State University).
See this site for an extensive list of annotated pointers to on-line network research, including: introductory readings; research sites; software, toolkits, and computer demos; books and journals; and resource sites, groups, and individual researchers.
- A site devoted more specifically to agent-based research focusing on the
Formation and Evolution of Interaction Networks
is maintained by Leigh Tesfatsion (Economics, Iowa State University).
See this site for an extensive list of annotated pointers to on-line agent-based network research, including: introductory readings; general readings; software, toolkits, and computer demos; and resource sites, groups, and individual researchers.
-
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.
- 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.
- 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
Richard Dawkins Foundation for Reason and Science (US) maintains a website devoted to the support of scientific education, critical thinking, and evidence-based understanding of the natural world, inspired by the work of Richard Dawkins.
Site resources include news items, books, writings, quotes, videos, software, biographical information, and links.
- The
Tree of Life (ToL)
project is a collaborative effort of biologists and nature enthusiasts from around the world. On more than 10,000 World Wide Web pages, the project provides information about biodiversity, the characteristics of different groups of organisms, and their evolutionary history (phylogeny).
- The Biological Modeling and Visualization (BMV) Research Group in the Department of Computer Science at the University of Calgary, Canada, maintain a site titled
Algorithmic Botany.
The BMV group studies the modeling, simulation, and visualization of plants. 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 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 Los Alamos National Laboratory's
Center for Nonlinear Studies,
formed in 1980, organizes research related to nonlinear and complex systems phenomena.
- The
Center for the Study of Complex Systems (CSCS)
at the University of Michigan is 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).
- 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.
- 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.
- 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.
-
Networks and Agent Networks (NaN)
is a research group spanning various units at Indiana
University-Bloomington, including informatics, cognitive science, physics, computer science, information science, and social science. The group is interested in exploring broad areas of complex systems that involve networks issues.
- The
Computer Graphics 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.
- 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.
- The
International Microsimulation Association (IMA) ,
launched in 2005, aims to promote the free interchange of experiences and ideas etween practioners of microsimulation worldwide.
The IMA publishes the peer-reviewed online journal
The International Journal of Microsimulation.
- 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.
- Thomas S. Ray (Zoology, University of Oklahoma, Norman, OK) 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."
- 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."
-
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 (Michigan State University) founded the
Digital Evolution Laboratory (DevoLab)
at MSU in 1999. The group performs experimental studies on digital organisms withthe twin goals of improving understanding of how natural evolution works, and applying this knowledge to solving computational, engineering, and biological problems.
-
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 featuring
Karl Sims' 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.
- 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 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,
and infobots, among other related concepts.
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.
- The
Center for Adaptive Behavior and Cognition (ABC)
is directed by Prof. Dr. Gerd Gigerenzer (Max Planck Institute, Berlin). ABC encompasses an interdisciplinary and international research group focusing on the following key question: How dohumans and other animals make decisions under uncertainty, that is, when time and information are limited and the future is unknown?
- 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
AI Game Programmers Guild Homepage.
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.
- The
Stanford Encyclopedia of Philosophy Web Site,
edited by Edward N. Zalta (Stanford University),
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."
- 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.
- Leigh Tesfatsion (Iowa State University, Ames) maintains a
website titled
Adaptive Computation Methods for Nonlinear Systems.
Methods (with software implementations) featured at this site include: nonlocal automated sensitivity analysis (NASA), for the tracking of solutions for parameterized nonlinear systems over parameter intervals; tracking of eigenvalues and eigenvectors for parameterized matrices over parameter intervals; adaptive homotopy continuation; and the FEED algorithm for the fast efficient evaluation of higher-order partial derivatives.
- 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 -- now known as the James Hutton Research Institute -- have conducted 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.
- The MLURI researchers concluded 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 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.
- 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.
- 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
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.
- 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 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.
- 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, University of Hamburg, Germany)
maintains a web site on
Entropy on the Worldwide Web.
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. The
Adam Smith Global Foundation,
launched in 2012 in Adam Smith’s birth town of Kirkcaldy, provides pointers to many source materials relating to Smith's work.
- 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/Rk,
where the exponent k is close to unity. Wentian Li maintains a website titled
Zipf's Law
that provides archival access to numerous works related to Zipf's Law.
Copyright © Leigh Tesfatsion. All Rights Reserved.