Formation of Segregated and Integrated Groups

A model of group formation is presented where the number of groups is fixed and a person can only join a group if the group’s members approve the person’s joining. Agents have either local status preferences (each agent wants to be the highest status agent in his group) or global status preferences (each agent wants to join the highest status group that she can join). For both preference types, conditions are provided which guarantee the existence of a segregated stable partition where similar people are grouped together and conditions are provided which guarantee the existence of an integrated stable partition where dissimilar people are grouped together. Additionally, in a dynamic framework we show that if a new empty group is added to a segregated stable partition, then integration may occur.Group Formation, Stable Partition, Segregation, Integration

Equilibrium Existence in Bipartite Social Games: A Generalization of Stable Matchings

We prove existence of equilibria in bipartite social games, where players choose both a strategy in a game and a partner with whom to play the game. Such social games generalize the well-known marriage problem where players choose partners but do not take actions subsequent to matching.Social Games

On the Formation of Interaction Networks in Social Coordination Games

There are many situations where two interacting individuals can benefit from coordinating their actions. We examine the endogenous choice of partners in such social coordination games and the implications for resulting play. We model the interaction pattern as a network where individuals periodically have the discretion to add or sever links to other players. A player chooses whether to add or sever a link based on the (prospective) partner's past behavior. With such endogenous interaction patterns we see multiple stochastically stable states of play, including some that involve play of equilibria in the coordination game that are neither efficient nor risk dominant.

Social Games: Matching and the Play of Finitely Repeated Games

We examine a new class of games, which we call social games, where players not only choose strategies but also choose with whom they play. A group of players who are dissatisfied with the play of their current partners can join together and play a new equilibrium. This imposes new refinements on equilibrium play, where play depends on the relative populations of players in different roles, among other things. We also examine finite repetitions of games where players may choose to rematch in any period. Some equilibria of fixed-player repeated games cannot be sustained as equilibria in a repeated social game. Conversely, the set of repeated matching (or social) equilibria also includes some plays that are not part of any subgame perfect equilibrium of the corresponding fixed-player repeated games. We explore existence under different equilibrium definitions, as well as the relationship to renegotiation-proof equilibrium. It is possible for repeated matching equilibria to be completely distinct from renegotiation-proof equilibria, and even to be Pareto inefficient.Social games, Matching, Games, Repeated games, Renegotiation

Social Games: Matching and the Play of Finitely Repeated Games

We examine a new class of games, which we call social games, where players not only choose strategies but also choose with whom they play. A group of players who are dissatisfied with the play of their current partners can join together and play a new equilibrium. This imposes new refinements on equilibrium play, where play depends on the relative populations of players in different roles, among other things. We also examine finite repetitions of games where players may choose to rematch in any period. Some equilibria of fixed-player repeated games cannot be sustained as equilibria in a repeated social game. Conversely, the set of repeated matching (or social) equilibria also includes some plays that are not part of any subgame perfect equilibrium of the corresponding fixed-player repeated games. We explore existence under different equilibrium definitions, as well as the relationship to renegotiation-proof equilibrium. It is possible for repeated matching equilibria to be completely distinct from renegotiation-proof equilibria, and even to be Pareto inefficient.Social Games, Matching, Games, Repeated Games, Renegotiation

Non-Myopic Formation of Circle Networks

We examine the dynamic formation of networks by self-interested individuals who can form and sever links. We assume that agents are initially unconnected, that the cost of forming a first link exceeds its benefits, and that indirect links are valuable. We show that if agents are nonmyopic then it is possible for a network shaped like a circle to form

Formation of Segregated and Integrated Groups

There are many situations where people join groups, the number of groups is fixed, and where a person can only join a new group if the new group approves the person’s joining. We examine such situations where agents are concerned with either local status (each agent wants to be the highest status agent in his group) or global status (each agent wants to join the highest status group that she can join). For both cases, conditions are provided under which a segregated stable partition of groups form where similar people are grouped together and conditions are provided under which an integrated stable partition of groups form where dissimilar people are grouped together. We also show that the addition of an empty group (or location) to a segregated stable partition of groups may cause integration to occur

Career and Family Choices in the Presence of Uncertainty

It is well known that women\u27s career outcomes are tied to fertility decisions and that occasionally educated women who had planned to stay in the labor market after childbirth exit the market. We examine women\u27s career, fertility, and educational choices in an environment of uncertainty regarding the possibility of achieving both a high-powered career and a family. In a simple framework, we show that although women may prefer to have both a prestigious career and a family they may choose a less prestigious job or no family due to the uncertainty involved in being able to achieve both a career and family. In an overlapping generations model, we examine how women\u27s beliefs about the probability of a career separation due to family obligations are formulated and show that a simple belief updating structure exists in which future generations\u27 beliefs may converge and certainly do not diverge from the true probability of a career separation. Lastly, we examine the impact of grandparent child care networks on career and family choices in both a static and overlapping generations model