How Do Voters Evaluate the Age of Politicians?

In most countries, elected officials tend to be older than most of their constituents. Is this because voters generally prefer older politicians to younger ones? We investigate this question by conducting two novel survey experiments in Japan. We ask respondents to evaluate the photos of hypothetical candidates for mayor while altering candidates' faces using artificial neural networks to make them appear as if they are younger or older. Contrary to the observed age demographics of politicians, we find that respondents dislike older candidates the most, but view younger and middle-aged candidates as equally favorable. Moreover, while younger and middle-aged respondents prefer candidates closer to their own age, older respondents do not. Respondents rate older candidates as the least competent, least physically attractive, least likely to focus on most policy issues, and least electable. Together, these findings suggest that supply-side factors rather than voter demand explain the shortage of younger politicians.