Why is religiosity in contemporary America exceptionally high relative to those in other rich countries? I develop a simple theory that hinges on the sense of security of immigrant-identity, which is informed by both religion and ethnicity. Commitments to religion and to ethnicity are...

We offer a theory of gender differences in parental altruism based on the asymmetry that female fertility is constrained but male fertility is relatively unconstrained. Modelling human preferences as having been shaped during the Pleistocene, we derive evolutionarily stable, co-evolved male and...

We study different methods of immigration control using a simple model of a congested world. Our main comparison involves quota, the predominant instrument of immigration control, and a proposed system of immigration tolls and emigration subsidies. We show that the equilibrium of the proposed...

We consider a world in which the mode of food production, foraging or agriculture, is endogenous, and in which technology grows exogenously. Using a recent model of coalition formation, we allow individuals to rationally form cooperative communities (bands) of foragers or farmers. At the lowest...

Empirical research on the organization of firms requires that firms be classified on the basis of their control structures. This should be done in a way that can potentially be made operational. It is easy to identify the ultimate controller of a hierarchical organization, and the literature has...