Learning about Voter Rationality

An important empirical literature evaluates whether voters are rational by examining how electoral outcomes respond to events outside the control of politicians, such as natural disasters or economic shocks. The argument is that rational voters should not base electoral decisions on such events, so evidence that these events affect electoral outcomes is evidence of voter irrationality. We show that such events can affect electoral outcomes, even if voters are rational and have instrumental preferences. The reason is that these events change voters' opportunities to learn new information about incumbents. Thus, identifying voter (ir)rationality requires more than just identifying the impact of exogenous shocks on electoral fortunes. Our analysis highlights systematic ways in which electoral fortunes are expected to change in response to events outside incumbents' control. Such results can inform empirical work attempting to identify voter (ir)rationality.