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 Barry Wellman
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  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
  http://www.chass.utoronto.ca/~wellman fax:+1-416-978-3963
  Updating history: http://chass.utoronto.ca/oldnew/cybertimes.php
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Promotion of cooperation induced by nonuniform payoff allocation in
spatial public goods game , Eur. Phys. J. B

Abstract: A nonuniform payoff allocation mechanism is proposed for spatial
public goods games where individuals are nodes on a scale-free network.
Each individual is assigned a weight kiα, where ki is the degree of
individual i and α is an adjustable parameter that controls the degree of
diversity in individuals' profits. During the evolution progress, the
allocation of payoff on individual i is assumed to be proportional to its
weight. Individuals synchronously update their strategies according to the
stochastic rule with a fixed noise level. It is found that there exists an
optimal value of Î ± which yields the highest level of cooperation. Other
pertinent quantities, including the payoff and the probability of finding
a node playing as cooperator versus the degree, are also investigated
computationally and analytically. Our results suggest that a suitable
degree of diversity among individuals can promote the emergence of
cooperation.

* [18] Promotion of cooperation induced by nonuniform payoff allocation in
spatial public goods game, D. Peng, H.-X. Yang, W.-X. Wang, G. R. Chen and
B.-H. Wang, 2010/01/15, DOI: 10.1140/epjb/e2010-00008-7, Eur. Phys. J. B
[18] http://dx.doi.org/10.1140/epjb/e2010-00008-7

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 Optimal Synchronization in Space , arXiv

Excerpt: In this Rapid Communication we investigate spatially constrained
networks that realize optimal synchronization properties. After arguing
that spatial constraints can be imposed by limiting the amount of `wire'
available to connect nodes distributed in space, we use numerical
optimization methods to construct networks that realize different
trade-offs between optimal synchronization and spatial constraints.

* [19] Optimal Synchronization in Space, Markus Brede, 2010/01/,
arXiv:1001.4921 [19] http://arXiv.org/abs/1001.4921

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