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  Barry Wellman

   S.D. Clark Professor of Sociology, FRSC               NetLab Director
   Department of Sociology                  725 Spadina Avenue, Room 388
   University of Toronto   Toronto Canada M5S 2J4   twitter:barrywellman             fax:+1-416-978-3963
   Updating history:

Cooperation through imitation and exclusion in networks , Journal of
Economic Dynamics and Control

abstract: We study the coevolution of networks and action choices in a 
Prisoners' Dilemma. Agents in our model learn about both action choices 
and choices of interaction partners (links) by imitating successful 
behavior of others. The resulting dynamics yields outcomes where both 
cooperators and defectors coexist under a wide range of parameters. Two 
scenarios can arise. Either there is full separation of defectors and 
cooperators, i.e. they are found in two different, disconnected 
components. Or there is marginalization of defectors, i.e. connected 
networks emerge with a center of cooperators and a periphery of defectors.

* [28] Cooperation through imitation and exclusion in networks, Fosco C , 
Mengel F, December 2010, DOI: 10.1016/j.jedc.2010.12.002, Journal of 
Economic Dynamics and Control, in Press



13.01. Models of coalition or alliance formation , Journal of Theoretical

Abstract: More than half a century has now elapsed since coalition or 
alliance formation theory (CAFT) was first developed. During that time, 
researchers have amassed a vast amount of detailed and high-quality data 
on coalitions or alliances among primates and other animals. But models 
have not kept pace, and more relevant theory is needed. In particular, 
even though CAFT is primarily an exercise in polyadic game theory, game 
theorists have devoted relatively little attention to questions that 
motivate field research, and much remains largely unexplored. The state of 
the art is both a challenge and an opportunity. In this review we describe 
a variety of game-theoretic and related modelling approaches that have 
much untapped potential to address the questions that field biologists 

* [30] Models of coalition or alliance formation, Mesterton-Gibbons M ,
Gavrilets S , Gravner J , Akçay E, December 2010, DOI:
10.1016/j.jtbi.2010.12.031, Journal of Theoretical Biology, in Press
* Contributed by [31] Segismundo

18. New System for Analyzing Information on WikiLeaks, Social Media ,

Excerpts: () has designed a system for exploring information on networks 
or graphs that can complement internet search engines and is of particular 
interest in areas related to social media, the internet, biomedicine, 
fraud detection, education and advanced bibliographic searches. () the 
technology can be used to extract information from WikiLeaks from two 
perspectives: one, to obtain generic indicators that provide information 
on whether the data network has the features of a social network and 
whether communities of data are created that can provide relevant 
information; and two, to use the documents hosted on the website to 
analyze how a topic evolves over time, ().

* [38] New System for Analyzing Information on WikiLeaks, Social Media,
2011/01/04, ScienceDaily & Universitat Politcnica de Catalunya


19.03. Introduction to Complexity and Complex Systems , CRC Press

Summary:  The boundaries between simple and complicated, and complicated 
and complex system designations are fuzzy and debatable, even using 
quantitative measures of complexity. However, if you are a biomedical 
engineer, a biologist, physiologist, economist, politician, stock market 
speculator, or politician, you have encountered complex systems. 
Furthermore, your success depends on your ability to successfully interact 
with and manage a variety of complex systems. In order not to be 
blindsided by unexpected results, we need a systematic, comprehensive way 
of analyzing, modeling, and simulating complex systems to predict 
non-anticipated outcomes. (...)

* [43] Introduction to Complexity and Complex Systems, Robert B. Northrop,
2010/12/08, CRC Press

19.04. Chaos: The Science of Predictable Random Motion , Oxford University

Summary:  Based on only elementary mathematics, this engaging account of 
chaos theory bridges the gap between introductions for the layman and 
college-level texts. It develops the science of dynamics in terms of small 
time steps, describes the phenomenon of chaos through simple examples, and 
concludes with a close look at a homoclinic tangle, the mathematical 
monster at the heart of chaos. The presentation is enhanced by many 
figures, animations of chaotic motion (available on a companion CD), and 
biographical sketches of the pioneers of dynamics and chaos theory. (...)

* [45] Chaos: The Science of Predictable Random Motion, Richard Kautz,
2010/12/30, Oxford University Press

19.05. Networks of the Brain , The MIT Press

Summary:  Over the last decade, the study of complex networks has expanded 
across diverse scientific fields. Increasingly, science is concerned with 
the structure, behavior, and evolution of complex systems ranging from 
cells to ecosystems. Modern network approaches are beginning to reveal 
fundamental principles of brain architecture and function, and in this 
book, Olaf Sporns describes how the integrative nature of brain function 
can be illuminated from a complex network perspective. Highlighting the 
many emerging points of contact between neuroscience and network science, 
the book serves to introduce network theory to neuroscientists and 
neuroscience to those working on theoretical network models. (...)

* [47] Networks of the Brain, Olaf Sporns, 2011/11/30, The MIT Press

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