Self-serving incentives impair collective decisions by increasing conformity

Autoři: Sepideh Bazazi aff001;  Jorina von Zimmermann aff002;  Bahador Bahrami aff003;  Daniel Richardson aff002
Působiště autorů: Independent researcher, London, United Kingdom aff001;  Department of Experimental Psychology, University College London, London, United Kingdom aff002;  Institute of Cognitive Neuroscience, University College London, London, United Kingdom aff003
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
doi: 10.1371/journal.pone.0224725


The average judgment of large numbers of people has been found to be consistently better than the best individual response. But what motivates individuals when they make collective decisions? While it is a popular belief that individual incentives promote out-of-the-box thinking and diverse solutions, the exact role of motivation and reward in collective intelligence remains unclear. Here we examined collective intelligence in an interactive group estimation task where participants were rewarded for their individual or group’s performance. In addition to examining individual versus collective incentive structures, we controlled whether participants could see social information about the others’ responses. We found that knowledge about others’ responses reduced the wisdom of the crowd and, crucially, this effect depended on how people were rewarded. When rewarded for the accuracy of their individual responses, participants converged to the group mean, increasing social conformity, reducing diversity and thereby diminishing their group wisdom. When rewarded for their collective performance, diversity of opinions and the group wisdom increased. We conclude that the intuitive association between individual incentives and individualist opinion needs revising.

Klíčová slova:

Bayesian method – Behavior – Decision making – Experimental design – Intelligence – Motivation – Social influence – Human intelligence


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Článek vyšel v časopise


2019 Číslo 11