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

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.