Eur. Phys. J. B 76, 147-156 (2010)
https://doi.org/10.1140/epjb/e2010-00179-1

Network evolution based on minority game with herding behavior

¹ Instituto de Física – Universidade de Brasília, 70910-900 DF, Brazil
² Instituto de Física – Universidade Federal da Bahia, Salvador, 40210-340 BA, Brazil
³ Departamento de Economia – Universidade de Brasília, 70910-900 DF, Brazil
⁴ Instituto Nacional de Ciência e Tecnologia de Sistemas Complexos, Brazil

Corresponding author: ^a bernardo@fis.unb.br

Received: 31 August 2009
Revised: 29 March 2010
Published online: 17 June 2010

Abstract

The minority game (MG) is used as a source of information to design complex networks where the nodes represent the playing agents. Differently from classical MG consisting of independent agents, the current model rules that connections between nodes are dynamically inserted or removed from the network according to the most recent game outputs. This way, preferential attachment based on the concept of social distance is controlled by the agents wealth. The time evolution of the network topology, quantitatively measured by usual parameters, is characterized by a transient phase followed by a steady state, where the network properties remain constant. Changes in the local landscapes around individual nodes depend on the parameters used to control network links. If agents are allowed to access the strategies of their network neighbors, a feedback effect on the network structure and game outputs is observed. Such effect, known as herding behavior, considerably changes the dependence of volatility σ on memory size: it is shown that the absolute value of σ as well as the corresponding value of memory size depend both on the network topology and on the way along which the agents make their playing decisions in each game round.