We calculate the equilibrium fraction of cooperators in a population in which payoffs accrue from playing a single-shot prisoner's dilemma game. Individuals who are hardwired as cooperators or defectors are randomly matched into pairs, and cooperators are able to perfectly find out the type of a...

This paper asks whether population growth is conducive to the sustainability of cooperation. A simple model is developed in which farmers who live around a circular lake engage in trade with their adjacent neighbors. The payoffs from this activity are governed by a prisoner's dilemma rule of...

A migration network is modeled as a mutually beneficial cooperative agreement between financially-constrained individuals who seek to finance and expedite their migration. The cooperation agreement creates a network: established migrants contract to support the subsequent migration of others in...

Strong ties with the home country and with the host country can coexist. An altruistic migrant who sends remittances to his family back home assimilates more the more altruistic he is, and also more than a non-remitting migrant.

Consider a population of farmers who live around a lake. Each farmer engages in trade with his m adjacent neighbors, where m is termed the span of interaction. Trade is governed by a prisoner's dilemma rule of engagement. A farmer's payoff is the sum of the payoffs from the m prisoner's dilemma...

Quite often, migrants appear to exert little effort to absorb the mainstream culture and to learn the language of their host society, even though the economic returns (increased productivity and enhanced earnings) to assimilation are high. We show that when interpersonal comparisons affect...

Consider a population of farmers who live around a lake. Each farmer engages in trade with his two adjacent neighbors. The trade is governed by a prisoner's dilemma 'rule of engagement'. A farmer's payoff is the sum of the payoffs from the two prisoner's dilemma games played with his two...

In a haystack-type representation of a heterogeneous population that is evolving according to a payoff structure of a prisoner's dilemma game, migration is modeled as a process of swapping" individuals between heterogeneous groups of constant size after a random allocation fills the haystacks,...

In a haystack-type representation of a heterogeneous population that is evolving according to a payoff structure of a prisoner’s dilemma game, migration is modeled as a process of “swapping” individuals between heterogeneous groups of constant size after a random allocation fills the...