A statistical test for the optimality of deliberative time allocation

  • Rahul BhuiEmail author
Theoretical Review


Whenever we make a choice, we must also decide how much time to spend making it. Many theories of decision-making crucially assume that this deliberation perfectly balances the costs of time expenditure and the benefits of better decisions. However, might we “overthink” or “underthink” decisions? Here, I propose and implement a method to precisely determine whether people are optimally spending their time on deliberation, accounting for individual preferences. This test evaluates the consistency of underlying preferences for time when incentives change, which is a necessary condition for optimality. This enables a more comprehensive analysis of rationality in a variety of contexts. I demonstrate how the test can reveal departures from optimality using two motion discrimination experiments in which I vary task difficulty and monetary incentives.


Decision making Response time Optimality Speed-accuracy tradeoff Sequential sampling models 



Thanks to Colin Camerer, Jaron Colas, Hayley Dorfman, Sam Gershman, Taisuke Imai, Ian Krajbich, and Tomasz Strzalecki for helpful comments and discussions. Funding from the Social Sciences and Humanities Research Council of Canada and the Harvard Mind Brain Behavior Interfaculty Initiative is gratefully acknowledged.

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Copyright information

© The Psychonomic Society, Inc. 2019

Authors and Affiliations

  1. 1.Departments of Psychology and Economics & Center for Brain ScienceHarvard UniversityCambridgeUSA

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