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(4 articles matched your search)

Societies, Cultures and Fisheries from a Modeling Perspective

Gérard Weisbuch and Guillemette Duchateau-Nguyen
Journal of Artificial Societies and Social Simulation 1 (2) 2

Abstract: Cultures can be viewed as sets of beliefs and techniques allowing societies to cope with their environment. We here propose simple and explicit schemes showing how fishermen could encode beliefs about a renewable resource, fish. We then discuss the dynamics of the society, represented by economic and cultural variables, coupled to the fishery represented by fish abundance. According to different coding schemes and sets of parameters, several dynamical regimes are observed, including one with endogenous crises.

How Can Extremism Prevail? a Study Based on the Relative Agreement Interaction Model

Guillaume Deffuant, Frederic Amblard and Gérard Weisbuch
Journal of Artificial Societies and Social Simulation 5 (4) 1

Abstract: Abstract: We model opinion dynamics in populations of agents with continuous opinion and uncertainty. The opinions and uncertainties are modified by random pair interactions. We propose a new model of interactions, called relative agreement model, which is a variant of the previously discussed bounded confidence. In this model, uncertainty as well as opinion can be modified by interactions. We introduce extremist agents by attributing a much lower uncertainty (and thus higher persuasion) to a small proportion of agents at the extremes of the opinion distribution. We study the evolution of the opinion distribution submitted to the relative agreement model. Depending upon the choice of parameters, the extremists can have a very local influence or attract the whole population. We propose a qualitative analysis of the convergence process based on a local field notion. The genericity of the observed results is tested on several variants of the bounded confidence model.

The Results of Meadows and Cliff Are Wrong Because They Compute Indicator y Before Model Convergence

Guillaume Deffuant, Gérard Weisbuch, Frederic Amblard and Thierry Faure
Journal of Artificial Societies and Social Simulation 16 (1) 11

Abstract: Meadows and Cliff (2012) failed to replicate the results of Deffuant et al. (2002) and concluded that our paper was wrong. In this note, we show that the conclusions of Meadows and Cliff are due to a wrong computation of indicator y, which was not fully specified in our 2002 paper. In particular, Meadows and Cliff compute indicator y before model convergence whereas this indicator should be computed after model convergence.

Lattice Dynamics of Inequity

Gérard Weisbuch
Journal of Artificial Societies and Social Simulation 21 (1) 11

Abstract: We discuss a model of inequity based on iteration of the Nash multi-agent bargaining game on a lattice. Agent's choices are based on a logit function and gradual decay of memories of past profits. Numerical simulations demonstrate the stability of various dynamical regimes, such as disorder, fairness or inequity, according to parameters and initial conditions. When playing the game on a lattice i.e. using neighbouring agent interactions instead of random interaction among the whole agent population, one observes spatial domains and specific patterns in addition to the temporal convergence toward attractors observed when interactions involve any pair of agents. A result specific to the network topology is the co-existence of domains with different regimes, allowing the emergence of the inequity condition even in the absence of tags.