Opinion polls and other surveys are used to capture public sentiments on a variety of issues. If citizens are unwilling to reveal certain policy preferences to others, surveys may fail to characterize population preferences accurately. The innovation of this paper is to use unique data to...

We study how to promote compliance with rules in every day situations. Having access to unique data on the universe of users of all public libraries in Barcelona, we test the effect of sending email messages with different contents. We find that users return their items earlier if asked to do...