This article examines the effects of unemployment compensation when the size of the labor force depends on unemployment benefits. The analysis is based on an aggregate model with search and matching in which unemployment compensation affects the wage determination process and the number of jobs and workers. As with partial equilibrium models, unemployment compensation raises the unemployment rate and the ratio of unemployed to vacancies. However, wages may go up or down and firms may be better off. Generally, employed workers are worse off. Unemployment compensation transfers income from employed factors to unemployed factors, leading to greater input levels.

The paper develops a model of monopolistic competition in which the satisfaction levels consumers get from products are independently and identically distributed. Potential substitution among products then generates demand curves through the mechanism of order statistics. The value of extra variety can be calculated directly. Pareto, lognormal and beta distributions are investigated using numerical integration. Some but not all cases support the argument that the optimal number of firms exceeds the equilibrium number.

[A model is developed to describe the allocation of laborers to tasks. The relation between the distributions of earnings and abilities is found to depend on the presence of comparative advantage. Various features of the distribution of earnings are explained in terms of the time taken by a given grade of labor to perform a task of a given difficulty.]

THE presence or absence of comparative advantage is important to many fields of inquiry besides international trade. Recently, comparative advantage in the performance of tasks by individuals has been shown to be a minimum requirement for the distribution of labor earnings to be different in form from the distribution of abilities (Sattinger, 1975). In particular, skewness in the earnings distribution arises from comparative advantage. While many economists would take the existence of comparative advantage in individuals for granted, much economic analysis and empirical work depends on the absence of comparative advantage. Sherwin Rosen (1977) has recently analyzed the difficulties in labor aggregation introduced by the presence of comparative advantage. Also, the efficiency units assumption requires the absence of comparative advantage in individuals. In turn, the efficiency units assumption is necessary for empirical work relating the distribution of earnings solely to individual characteristics (Sattinger, 1977), as has often been done in the human capital literature. This paper uses data from mechanical aptitude tests (Paterson and Eliot et al., 1930) to investigate comparative advantage in the performance of tasks by individuals. Using both non-parametric and parametric tests, such comparative advantage is found to exist. The paper then presents a method for obtaining a measure of difficulty given a cardinal measure of abilities, and tests for the possibility of intransitive comparative advantage. Artificial economies are then constructed to reveal the effects of comparative advantage on the distribution of earnings. II. Sources of Comparative Advantage

A model of equilibrium unemployment and vacancies is presented in which the absence of a market for interviews can yield externalities and inefficiency. Inefficiency results in market forces that lead firms to charge fees for interviews or to change the wage rate. These market forces require substantial information and may not operate. A graphical analysis shows how such forces would cause wages to adjust to shifts in supply, taxes, and transfers between workers and firms. With excessive unemployment, efficiency requires a transfer of income from workers to firms.