This paper uses the Panel Study of Income Dynamics to study the intertemporal preferences of rich and poor households in the United States. Subjective rates of time preferences, identified from estimation of consumption Euler equations, are three to five percentage points higher for households with low permanent incomes than for those with high permanent incomes. Controlling for race and education widens this difference. With age and family composition held constant, time preference rates vary from 12 percent for white, college-educated families in the top 5 percent of the labor income distribution to 19 percent for nonwhite families without a college education whose labor incomes are in the bottom fifth percentile.

This paper uses the Panel Study of Income Dynamics to study the intertemporal preferences of rich and poor households in the United States. Subjective rates of time preference, identified from estimation of consumption Euler equations, are three to five percentage points higher for households with low permanent incomes than for those with high permanent incomes. Controlling for race and education widens this difference. With age and family composition held constant, time preference rates vary from 12 percent for white, college-educated families in the top 5 percent of the labor income distribution to 19 percent for nonwhite families without a college education whose labor incomes are in the bottom fifth percentile. Such differences imply very different patterns of consumption over the life cycle and suggest one possible explanation for observed heterogeneity in savings behavior across socioeconomic classes.

On the basis of anthropologists' area-specific research of primogeniture, I propose a Becker-Barro type of dynastic model in which primogeniture may emerge as family heads' optimal policy to minimize their respective lineal extinction probability. I show that parents' bequest division will be affected by the intrinsic mobility structure of the society, contrary to previous causality conjecture. Although an unequal division of bequests widens the within-generation inequality, it may increase the intergenerational upward mobility for the well-endowed child, which in turn improves the originally rigid upward mobility of the poor and middle-income groups and, as a result, reduces the steady-state income inequality.

On the basis of anthropologists' area-specific research of primogeniture, I propose a Becker-Barro type of dynastic model in which primogeniture may emerge as family heads' optimal policy to minimize their respective lineal extinction probability. I show that parents' bequest division will be affected by the intrinsic mobility structure of the society, contrary to previous causality conjecture. Although an unequal division of bequests widens the within-generation inequality, it may increase the intergenerational upward mobility for the well-endowed child, which in turn improves the originally rigid upward mobility of the poor and middle-income groups and, as a result, reduces the steady-state income inequality.

This paper proposes an empirical framework for measuring the effects of entry in concentrated markets. Building on models of entry in atomistically competitive markets, we show how the number of producers in an oligopolistic market varies with changes in demand and market competition. These analytical results structure our empirical analysis of competition in five retail and professional industries. Using data on geographically isolated monopolies, duopolies, and oligopolies, we study the relationship between the number of firms in a market, market size, and competition. Our empirical results suggest that competitive conduct changes quickly as the number of incumbents increases. In markets with five or fewer incumbents, almost all variation in competitive conduct occurs with the entry of the second or third firm. Surprisingly, once the market has between three and five firms, the next entrant has little effect on competitive conduct.

This paper proposes an empirical framework for measuring the effects of entry in concentrated markets. Building on models of entry in atomistically competitive markets, the authors show how the number of producers in an oligopolistic market varies with changes in demand and market competition. These analytical results structure the authors' empirical analysis of competition in five retail and professional industries. Using data on geographically isolated monopolies, duopolies, and oligopolies, they study the relationship between the number of firms in a market, market size, and competition. The authors' empirical results suggest that competitive conduct changes quickly as the number of incumbents increases.