On the Size and Structure of Group Cooperation

This paper examines characteristics of cooperative behavior in a repeated, n-person, continuous action generalization of a Prisoner’s Dilemma game. When time preferences are heterogeneous and bounded away from one, how “much” cooperation can be achieved by an ongoing group? How does group cooperation vary with the group’s size and structure? For an arbitrary distribution of discount factors, we characterize the maximal average cooperation (MAC) likelihood of this game. The MAC likelihood is the highest average level of cooperation, over all stationary subgame perfect equilibrium paths, that the group can achieve. The MAC likelihood is shown to be increasing in monotone shifts, and decreasing in mean preserving spreads, of the distribution of discount factors. The latter suggests that more heterogeneous groups are less cooperative on average. Finally, we establish weak conditions under which the MAC likelihood exhibits increasing returns to scale when discounting is heterogeneous. That is, larger groups are more cooperative, on average, than smaller ones. By contrast, when the group has a common discount factor, the MAC likelihood is invariant to group size.Repeated games ; maximal average cooperation likelihood ; heterogeneous discount factors ; returns to scale JEL Classification: C7 ; D62 ; D7

Social Norms, Local Interaction, and Neighborhood Planning

This paper examines optimal social linkage when each individual's repeated interaction with each of his neighbors creates spillovers. Individuals differ across rates of time preference. A planner must choose a local interaction system or neighborhood design before observing the realization of these rates. Given the planner's choice of design and a realization of discount factors, each individual plays a repeated Prisoner's Dilemma game with his neighbors. We introduce the concept of a local trigger strategy equilibrium (LTSE) to describe a stationary sequential equilibrium in which, for any realization of discount factors, each individual conditions his cooperation on the cooperation of at least one "acceptable" group of neighbors. The presence of impatient types implies that some free riding may be tolerated in equilibrium. When residents' discount factors are known to the planner, the optimal design exhibits a cooperative "core" and an uncooperative "fringe." Uncooperative (impatient) types are connected to cooperative ones who tolerate their free riding so that social conflict is kept to a minimum. By contrast, when residents' discount factors are independently distributed, the optimal design partitions individuals into maximally connected cliques (e.g., cul-de-sacs). In that case, each person's cooperation decision becomes a pure local public good. Finally, if types are correlated, then incomplete graphs with small overlap (e.g., grids) are possible.repeated games, local interaction, social norms, neighborhood design, local trigger strategy

On the Size and Structure of Group Cooperation

This paper examines characteristics of cooperative behavior in a repeated, n-person, continuous action generalization of a Prisoner’s Dilemma game. When time preferences are heterogeneous and bounded away from one, how “much” cooperation can be achieved by an ongoing group? How does group cooperation vary with the group’s size and structure? For an arbitrary distribution of discount factors, we characterize the maximal average co-operation (MAC) likelihood of this game. The MAC likelihood is the highest average level of cooperation, over all stationary subgame perfect equilibrium paths, that the group can achieve. The MAC likelihood is shown to be increasing in monotone shifts, and decreasing in mean preserving spreads, of the distribution of discount factors. The latter suggests that more heterogeneous groups are less cooperative on average. Finally, we establish weak conditions under which the MAC likelihood exhibits increasing returns to scale when discounting is heterogeneous. That is, larger groups are more cooperative, on average, than smaller ones. By contrast, when the group has a common discount factor, the MAC likelihood is invariant to group size.Repeated games, Maximal average Cooperation likelihood, Heterogeneous discount factors, Returns to scale

One Size and Structure of Group Cooperation

This paper examines characteristics of cooperative behavior in a repeated, n-person, continuous action generalization of a Prisoner's Dilemma game. When time preferences are heterogeneous and bounded away from one, how "much" cooperation can be achieved by an ongoing group? How does group cooperation vary with the group's size and structure? For an arbitrary distribution of discount factors, we characterize the maximal average cooperation (MAC) likelihood of this game. The MAC likelihood is the highest average level of cooperation, over all stationary subgame perfect equilibrium paths, that the group can achieve. The MAC likelihood is shown to be increasing in monotone shifts, and decreasing in mean preserving spreads, of the distribution of discount factors. The latter suggests that more heterogeneous groups are less cooperative on average. Finally, we establish weak conditions under which the MAC likelihood exhibits increasing returns to scale when discounting is heterogeneous. That is, larger groups are more cooperative, on average, than smaller ones. By contrast, when the group has a common discount factor, the MAC likelihood is invariant to group size.Repeated games, maximal average cooperation likelihood, heterogeneous discount factors, returns to scale

On the Size and Structure of Group Cooperation

This paper examines characteristics of cooperative behavior in a repeated, n-person, continuous action generalization of a Prisoner's Dilemma game. When time preferences are heterogeneous and bounded away from one, how does group cooperation vary with the group's size and structure? For an arbitrary distribution of discount factors, we characterize the maximal average cooperation (MAC) likelihood of this game. The MAC likelihood is the highest average level of cooperation, over all stationary subgame perfect equilibrium paths, in the group. We show that the MAC likelihood is increasing in monotone shifts, and decreasing in mean preserving spreads, of the distribution of discount factors. This suggests that more heterogeneous groups are less cooperative. Finally, we show under certain conditions that the MAC likelihood exhibits increasing returns to scale when discounting is heterogeneous: larger groups are more cooperative than smaller ones. By contrast, when discounting is homogeneous, the MAC likelihood is invariant to group size.Repeated games, maximal average cooperation likelihood, heterogeneous discount factors, returns to scale

On the Size and Structure of Group Cooperation

This paper examines characteristics of cooperative behavior in a repeated, n-person, continuous action generalization of a Prisoner's Dilemma game. When time preferences are heterogeneous and bounded away from one, how "much" cooperation can be achieved by an ongoing group? How does group cooperation vary with the group's size and structure? For an arbitrary distribution of discount factors, we characterize the maximal average cooperation (MAC) likelihood of this game. The MAC likelihood is the highest average level of cooperation, over all stationary subgame perfect equilibrium paths, that the group can achieve. The MAC likelihood is shown to be increasing in monotone shifts, and decreasing in mean preserving spreads, of the distribution of discount factors. The latter suggests that more heterogeneous groups are less cooperative on average. Finally, we establish weak conditions under which the MAC likelihood exhibits increasing returns to scale when discounting is heterogeneous. That is, larger groups are more cooperative, on average, than smaller ones. By contrast, when the group has a common discount factor, the MAC likelihood is invariant to group size.Repeated games, maximal average cooperation likelihood, heterogeneous discount factors, returns to scale

Determinants of long-term care insurance: Are spouses substitutes?

As the U.S. population continues to age due to medical advancements and the aging of the largest generation in the history of the U.S. (baby boomers), the number of people in long-term care facilities has increased significantly; however, the percentage of people with long-term care insurance is small. Research conducted in the early 2000s focused on factors such as availability of children, risk aversion, health status, age, having Medicaid, and other variables that describe personal attributes to explain why the market is so small. This paper will use recent data from the Health and Retirement Study to determine whether or not having a living spouse is a substitute for having long-term care insurance. In particular I investigated this question for those classified as middle baby-boomers. I found that being married has a positive and statistically significant impact on the whether or not an individual has long-term care insurance

On the size and structure of group cooperation

This paper examines characteristics of cooperative behavior in a repeated, n-person, continuous action generalization of a Prisoner’s Dilemma game. When time preferences are heterogeneous and bounded away from one, how “much” cooperation can be achieved by an ongoing group? How does group cooperation vary with the group’s size and structure? For an arbitrary distribution of discount factors, we characterize the maximal average co-operation (MAC) likelihood of this game. The MAC likelihood is the highest average level of cooperation, over all stationary subgame perfect equilibrium paths, that the group can achieve. The MAC likelihood is shown to be increasing in monotone shifts, and decreasing in mean preserving spreads, of the distribution of discount factors. The latter suggests that more heterogeneous groups are less cooperative on average. Finally, we establish weak conditions under which the MAC likelihood exhibits increasing returns to scale when discounting is heterogeneous. That is, larger groups are more cooperative, on average, than smaller ones. By contrast, when the group has a common discount factor, the MAC likelihood is invariant to group size