THE economic and demographic determinants of the labor force behavior of married females have been studied intensively.' Many of the important variables have now been isolated: education, age, income of husband, number of children, etc. However, as will be discussed below, the existing literature pays insufficient attention to the fact that U.S. income tax laws have placed a large burden on the earnings of married women. When a married couple chooses to enjoy the tax advantages of filing jointly, the first dollar earned by the wife is in effect taxed at the same marginal rate as the last dollar earned by the husband.2 The purpose of this paper is to present some empirical results on the impact of tax rates on the labor supply of married women. Explicit attention is focused on the extent to which individuals react to net rather than gross wages. The evidence strongly supports the view that it is the net wage that matters in the hours of work decision. Section I briefly discusses how taxes have been treated traditionally in the analysis of labor supply. Section II presents a model for examining the impact of taxes on labor supply, and section III contains the results of an empirical test of this model. A concluding section discusses work in progress which will refine and extend the results of this paper.

A common feature to most aggregative studies of the labor market is a marginal productivity expression in which the quantity of labor appears on the left hand side of the equation, and the right hand side includes the real wage and output. A number of researchers have cautioned that if the output variable is treated as exogenous, serious econometric difficulties may result. However, the assumption that output is exogenous has not been tested. In this paper, we estimate an equilibrium model of the labor market, and use it to test the assumption of output exogeneity. We find that the assumption that output is exogenous cannot be rejected by the data.

AN important question in contemporary 1AILeconomics is whether or not the real wage clears the labor market. Its answer has bearing on issues as diverse as the nature of unemployment, the efficacy of fiscal and monetary policies, and the incidence of income taxes. Unfortunately, consensus as to the correct answer seems to be lacking. While much of modern macroeconomic theory allows for the possibility that the real wage fails to equate the supply and demand of labor (Barro and Grossman, 1971; Korliras, 1975), much analysis is based on the assumption of equilibrium in the labor market (Patinkin, 1965). The purpose of the present paper is to carry out an econometric test for which view of the labor market is more appropriate. Although the model we build is very aggregative and much too crude to be used as a basis for policy, we believe that it provides a first step in making operational the theoretical literature on disequilibrium macro models. Our tentative conclusion is that the hypothesis of a labor market in continuous equilibrium must be rejected. In section II we describe briefly some earlier work on modelling the aggregate supply and demand for labor. It is shown that prior studies either assume equilibrium in the labor market, or deal with disequilibrium inadequately. In section III we specify the disequilibrium model. Section IV contains a discussion of estimation problems, an interpretation of the results, and a comparison with an equilibrium version of the model. A concluding section has a summary and an agenda for future research. II. Antecedents

We study the effects of a change in financial aid policy introduced by an anonymous university in 1998. Prior to that time, the university's financial aid packages for low-income students consisted of grants, loans, and campus jobs. After the change, the entire loan portion of the package for low-income students was replaced with grants. We find the program increased the likelihood of matriculation by low-income students by approximately 3 percentage points, although the effect is not statistically significant. The effect among low-income minority students was between 8 and 10 percentage points and statistically significant at the 10% level.

We study the effects of a change in financial aid policy introduced by a Northeastern university in 1998. Prior to that time, the university s financial aid packages for low income students consisted of grants, loans, and campus jobs. After the change, the entire loan portion of the package for low-income students was replaced with grants. We find the program increased the likelihood of matriculation by low-income students by about 3 percentage points, although the effect is not statistically significant. The effect among low-income minority students was about twice that size and statistically significant at the 10 percent level.

Modern empirical work on the choice between renting and owning focuses on the concept of the of housing, which integrates into a single measure the various components of housing costs. The standard approach implicitly assumes that households know the user cost of housing with certainty. However, the ex post user cost measure exhibits substantial variability over time, and it is highly unlikely that individuals believe themselves able to forecast these fluctuations with certainty. In this paper, we construct and estimate a model of the tenure choice that explicitly allows for the effects of uncertainty. The results suggest that previous work which ignored uncertainty may have overstated the effects of the income tax system upon the tenure choice.