American Political Science Review

Sources of Bias in Retrospective Decision Making: Experimental Evidence on Voters’ Limitations in Controlling Incumbents


a1 Yale University

a2 University of California–San Diego

a3 University of California–Berkeley


Are citizens competent to assess the performance of incumbent politicians? Observational studies cast doubt on voter competence by documenting several biases in retrospective assessments of performance. However, these studies are open to alternative interpretations because of the complexity of the real world. In this article, we show that these biases in retrospective evaluations occur even in the simplified setting of experimental games. In three experiments, our participants (1) overweighted recent relative to overall incumbent performance when made aware of an election closer rather than more distant from that event, (2) allowed an unrelated lottery that affected their welfare to influence their choices, and (3) were influenced by rhetoric to give more weight to recent rather than overall incumbent performance. These biases were apparent even though we informed and incentivized respondents to weight all performance equally. Our findings point to key limitations in voters’ ability to use a retrospective decision rule.


c1 Gregory A. Huber is Professor, Department of Political Science and Institution for Social and Policy Studies, Yale University, 77 Prospect Street, P.O. Box 208209, New Haven, CT 06520 (

c2 Seth J. Hill is Assistant Professor, Department of Political Science, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093 (

c3 Gabriel S. Lenz is Assistant Professor, Charles and Louise Travers Department of Political Science, University of California at Berkeley, 210 Barrows Hall #1950, Berkeley, CA 94720 (


  We thank John Bullock, Ignacio Esponda, Morris Fiorina, Alan Gerber, Marty Gilens, Austin Hart, Andy Healy, Aaron Kaufman, Neil Malhotra, Marc Meredith, Becky Morton, and Rob Van Howling, as well as seminar participants at Stanford and Princeton, for comments. A previous version of this article was presented at the 2011 American Political Science Association Annual Meeting, Seattle. Financial support for this project was provided by the Institution for Social and Policy Studies and the Center for the Study of American Politics at Yale University. Replication material is available at