, Volume 191, Issue 9, pp 1991–2007 | Cite as

Trust and the value of overconfidence: a Bayesian perspective on social network communication

  • Aron Vallinder
  • Erik J. OlssonEmail author


The paper presents and defends a Bayesian theory of trust in social networks. In the first part of the paper, we provide justifications for the basic assumptions behind the model, and we give reasons for thinking that the model has plausible consequences for certain kinds of communication. In the second part of the paper we investigate the phenomenon of overconfidence. Many psychological studies have found that people think they are more reliable than they actually are. Using a simulation environment that has been developed in order to make our model computationally tractable we show that in our model inquirers are indeed sometimes better off from an epistemic perspective overestimating the reliability of their own inquiries. We also show, by contrast, that people are rarely better off overestimating the reliability of others. On the basis of these observations we formulate a novel hypothesis about the value of overconfidence.


Trust Overconfidence Bayesianism Social network Communication Probability Reliability 



We would like to thank two anonymous referees for their input which led to many significant improvements and clarifications.


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Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  1. 1.Department of PhilosophyLund UniversityLundSweden

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