Female CEOs underperform their male counterparts in terms of shareholders’ returns by roughly 0.35% per month. This difference is significant, comparable to the in-sample value premium, somewhat smaller than the equity and momentum premia, and larger than the size premium.

The design of randomised controlled trials (RCTs) entails decisions that have economic, as well as statistical implications. In particular, the choice of an individual or cluster randomisation design may affect the cost of achieving the desired level of power, other things equal. Furthermore, if...