Fertility,Intra‐Generational Redistribution,and Social Security Sustainability

Incorporating heterogeneity in preference to having children into an overlapping generations model of a small open economy, we examine the effects of changes in the size of pay‐as‐you‐go (PAYG) social security on fertility choices of individuals and population growth of the economy. It is shown that PAYG social security will raise population growth by increasing the number of individuals who have children and the number of children parents have if the system involves redistribution between retirees with different contributions, whereas, if it has no redistribution, PAYG social security does not affect the fertility decisions of individuals.     

Migration decisions, expected remittances, and altruism

We investigate the effects of altruism on migration decisions by the potential migrant as well as the effects of altruism on remittances by the migrant to clarify how altruism affects remittances that the household in the home country will receive, i.e., expected remittances. Previous studies did not pay adequate attention to the effects of altruism on migration decisions of the potential migrant when examining the effects of altruism on remittances that will be sent from aboard. We find that if migration does not incur any costs, the potential migrant always migrates, and altruism increases expected remittances monotonically. On the other hand, if migration incurs costs, the potential migrant does not necessarily migrate, and the potential migrant with a higher degree of altruism is less likely to migrate. As a result, with migration costs, altruism may decrease expected remittances. Therefore, altruism does not increase expected remittances monotonically. Our results falsify the usual assumption of monotonicity regarding the effects of altruism on remittances.     

Corporate Social Responsibility or Payoff Asymmetry? A Study of an Endogenous Timing Game

We revisit an endogenous timing game by introducing corporate social responsibility into firms' payoffs. Previous research investigates an endogenous timing game in a mixed oligopoly, wherein one welfare‐maximizing public firm competes against profit‐maximizing private firms. It shows that the outcome is completely different from that of private oligopoly. In contrast to its result, we find that this change in payoff does not matter as long as the payoffs are symmetric. Our result indicates that asymmetry, and not welfare‐concerning objectives, yields specific results in the literature on mixed oligopoly.     

Endogenous longevity,public debt and endogenous growth

This study explores the mechanism that causes an inverted U-shaped relationship between the public debt to GDP ratio and the economic growth rate which is observed in empirical studies. We show that this relationship is caused even when the government does not introduce the golden rule of public finance, and government health care expenditure has important role in generating this relationship.     

The Nash bargaining solution in general n-person cooperative games

We present a noncooperative foundation for the Nash bargaining solution for an n-person cooperative game in strategic form. The Nash bargaining solution should be immune to any coalitional deviations. Our noncooperative approach yields a new core concept, called the Nash core, for a cooperative game based on a consistency principle. We prove that the Nash bargaining solution can be supported (in every subgame) by a stationary subgame perfect equilibrium of the bargaining game if and only if the Nash bargaining solution belongs to the Nash core.     

Endogenous Timing in Mixed Duopolies With Externality

We investigate endogenous timing in a mixed duopoly with a negative externality. We find that quantity (price) competition yields a simultaneous‐move (sequential‐move) outcome under a significant negative externality. These results indicate that mixed duopolies yield the same results as private duopolies under a significant negative externality, which is in sharp contrast to the results in mixed duopolies without a negative externality. Unless the negative externality is insignificant, public leadership yields greater welfare than private leadership, and public leadership is more robust than the private leadership as equilibrium. If optimal environmental tax policy is introduced, however, private leadership yields the greatest welfare and this an equilibrium outcome in the endogenous timing game under quantity competition.     

On pitfalls in the construction of family-based models of population growth: a note

Recently, several attempts have been made to construct an economic theory of population based on a formal theory of the family of the type developed by Becker in 1981, but there are serious limitations in all such efforts. The typical family's problem may have no solution, even with a well-behaved concave utility function. Moreover, even when the family's maximum problem has a unique solution, the phase diagram for the stock of capital may contain no steady state other than the origin. Finally, even when there exists a nontrivial steady state for the stock of capital, the community nevertheless may be destined for extinction. The first of these pitfalls concerns the internal consistency of the models, while the second and third concern the compatibility of the models with some gross facts of life. The pitfalls can be avoided, within the Becker framework by suitably restricting the family's utility and production functions, but the restrictions required are severe. This paper shows that, alternatively, the pitfalls sometimes can be avoided by going slightly outside the Becker framework, specifically, by modifying the typical family's budget constraint to allow explicitly for the cost of raising children. In particular, it is shown that, by this means, the pitfalls can be avoided even when the famil's utility function is log-linear, the example adduced by Kemp et al. In 1984 to demonstrate the existence of pitfalls. More precisely, it is shown that the family's maximum problem has a unique solution; that nontrival steady state exists; that, even if the steady state is locally unstable, the optimal trajectory tends neither to zero nor to infinity but to a 2-period limit cycle; and that survival is possible with quite general production functions. Thus, the end product is a logically consistent and reasonable model of economic development, with both population growth and capital accumulation firmly rooted in life-cycle family planning.     

Cooperation and Institution in Games

Based on recent developments in non‐cooperative coalitional bargaining theory, I review game theoretical analyses of cooperation and institution. First, I present basic results of the random‐proposer model and apply them to the problem of involuntary unemployment in a labour market. I discuss extensions to cooperative games with externalities and incomplete information. Next, I consider the enforceability of an agreement as an institutional foundation of cooperation. I re‐examine the contractarian approach to the problem of cooperation from the viewpoint that individuals may voluntarily create an enforcement institution.