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Temperature and outgroup discrimination

Published online by Cambridge University Press:  03 May 2021

Donghyun Danny Choi
Political Science, University of Pittsburgh, Pittsburgh, PA15260, USA
Mathias Poertner
International Affairs, Bush School of Government and Public Service, Texas A&M University, College Station, TX77843, USA
Nicholas Sambanis*
Political Science and Director, Identity and Conflict Lab, University of Pennsylvania, Philadelphia, PA19104, USA
*Corresponding author. Email:


High temperatures have been linked to aggression and different forms of conflict in humans. We consider whether exposure to heat waves increases discriminatory behavior toward outgroups. Using data from two large-scale field experiments in Germany, we find a direct causal effect of exposure to heat shocks on discrimination in helping behavior. As temperature rises, German natives faced with a choice to provide help to strangers in every-day interactions help Muslim immigrants less than they do other German natives, while help rates toward natives are unaffected by temperature. This finding suggests that there may be a physiological basis for discriminatory behavior toward outgroups.

Research Note
Copyright © The Author(s), 2021. Published by Cambridge University Press on behalf of the European Political Science Association

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All authors contributed equally to this work; their names are listed alphabetically.


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