The demographic history of the Jews in the Middle Ages may be characterized by two main phenomena: i) a sharp drop in the number of Jews until the beginning of the modern period, due mainly to conversions; and, ii) early urbanization. Until now, these features have been analyzed as primarily...

We investigate a setting in which members of a population, bifurcated into a majority and a minority, transact with randomly matched partners. All members are uniformly altruistic, and each transaction can be carried out cooperatively or through a market mechanism, with cooperative transactions...

Due to incomplete contracts, efficiency of an organization depends on willingness of individuals to take non-selfish actions, e.g., cooperate when there is no incentive to do so, or punish inefficient actions by others. Organizations also constitute a social boundary, or group. We investigate...

This paper studies the effect of endogenous group formation on the outcome in two types of coordination games with multiple Pareto-ranked equilibria. Endogenous group formation means that in each period players are free to choose among two or more groups within which they want to play the...

We study cheating as a collective-risk social dilemma in a group setting in which individuals are asked to report their actual outcomes. Misreporting their outcomes increases the individual's earnings but when the sum of claims in the group reaches a certain threshold, a risk of collective...

It takes a woman and a man to make a baby. This fact suggests that for a birth to take place, the parents should first agree on wanting a child. Using newly available data on fertility preferences and outcomes, we show that indeed, babies are likely to arrive only if both parents desire one, and...

Recent advances in behavioral genetics have enabled the discovery of genetic scores linked to a variety of economic outcomes, including education. We build on this progress to demonstrate that the same genetic variants that predict educational attainment independently predict household wealth in...