Arpad Abraham

Endogenous trading constraints with incomplete asset markets

This paper endogenizes the borrowing constraints on capital in a production economy with incomplete markets. We find that these limits get looser with income, a property that is consistent with US data on credit limits. The framework with endogenous limits is then used to study the effects of a revenue neutral tax reform that eliminates capital income taxes. Our results illustrate that it is very important to take into account the effects of tax policies on the limits. Throughout the transition, these effects can be big enough to change the overall conclusion about the desirability of a tax reform.

Efficient Allocations with Moral Hazard and Hidden Borrowing and Lending

We analyze a dynamic moral hazard setting, in which agents can borrow and lend and their decisions about effort, consumption and savings are private information. In contrast with previous findings, we show that as long as agents do not have perfect control over publicly observable outcomes, the efficient allocation is welfare improving with respect to the case where the agents can self insure only through borrowing and lending. We identify the main sources of welfare improvement, and we compute substantial efficiency gains. We provide a tractable recursive framework to study the optimal allocation in this setting. The dynamic programming formulation is based on a generalized first order approach, whose validity is verified ex post, using a parsimonious numerical procedure based on the recursive formulation itself.

On the first-order approach in principal agent models with hidden borrowing and lending

is monotone in output. We also investigate a few possibilities of relaxing these requirements.

EARNINGS INEQUALITY AND SKILL-BIASED TECHNOLOGICAL CHANGE WITH ENDOGENOUS CHOICE OF EDUCATION

This article analyzes the impact of stochastic skill-biased technological change on earnings inequality in a general equilibrium OLG model. Wage dispersion is determined by the heterogeneity of skills by allowing for productivity differences due to education, ability, and age. The model performs well in reproducing stylized facts on the time pattern of the U.S. wage distribution and human capital accumulation. In particular, it shows that slow adjustment of the supply of educated labor can itself explain the nonmonotonic time pattern of the college premium. (JEL: D31, J24, J31) (c) 2008 by the European Economic Association.