, Volume 64, Issue 1, pp 185–207 | Cite as

Microscopic modeling and analysis of collective decision making: equality bias leads suboptimal solutions

  • Pierluigi VellucciEmail author
  • Mattia Zanella


We discuss a novel microscopic model for collective decision-making interacting multi-agent systems. In particular we are interested in modeling a well known phenomena in the experimental literature called equality bias, where agents tend to behave in the same way as if they were as good, or as bad, as their partner. We analyze the introduced problem and we prove the suboptimality of the collective decision-making in the presence of equality bias. Numerical experiments are addressed in the last section.


Decision dynamics Opinion formation Collective behavior Multi-agent systems 

Mathematics Subject Classification

91B74 70K75 93B60 



PV would like to acknowledge Dr. Luigi Teodonio for his stimulating discussions about the topic of the paper. MZ acknowledges the ”Compagnia di San Paolo”.


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Copyright information

© Università degli Studi di Ferrara 2017

Authors and Affiliations

  1. 1.Department of EconomicsRoma Tre UniversityRomeItaly
  2. 2.Department of Mathematical SciencesPolitecnico di TorinoTurinItaly

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