Theory and Decision

, Volume 87, Issue 1, pp 87–122 | Cite as

Individual vs. group decision-making: an experiment on dynamic choice under risk and ambiguity

  • Enrica Carbone
  • Konstantinos GeorgalosEmail author
  • Gerardo Infante


This paper focuses on the comparison of individual and group decision-making, in a stochastic inter-temporal problem in two decision environments, namely risk and ambiguity. Using a consumption/saving laboratory experiment, we investigate behaviour in four treatments: (1) individual choice under risk; (2) group choice under risk; (3) individual choice under ambiguity and (4) group choice under ambiguity. Comparing decisions within and between decision environments, we find an anti-symmetric pattern. While individuals are choosing on average closer to the theoretical optimal predictions, compared to groups in the risk treatments, groups tend to deviate less under ambiguity. Within decision environments, individuals deviate more when they choose under ambiguity, while groups are better planners under ambiguity rather than under risk. Our results extend the often observed pattern of individuals (groups) behaving more optimally under risk (ambiguity), to its dynamic dimension.


Risk Ambiguity Inter-temporal optimisation Group decision-making Learning Experiment 


Supplementary material


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Authors and Affiliations

  1. 1.Department of Political Sciences “Jean Monnet”University of Campania “Luigi Vanvitelli”CasertaItaly
  2. 2.Department of EconomicsLancaster University Management SchoolLancasterUK
  3. 3.TorontoCanada

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