Why do people in rich countries not transfer more of their income to people in the world's poorest countries? To study this question and the relative importance of needs, entitlements, and nationality in people's social preferences, we conducted a real effort fairness experiment where people in...

There is a striking difference in income inequality and redistributive policies between the United States and Scandinavia. To study whether there is a corresponding cross-country difference in social preferences, we conducted the first large-scale international social preference experiment, with...

We report the results of a randomized controlled trial testing whether incentivizing physical exercise improves the academic performance of college students. As expected, the intervention increases physical activity. The main result is that it generates a strong and significant improvement in...