We study the incentives to improve ability in a model where heterogeneous firms and workers interact in a labor market characterized by matching frictions and costly screening. When effort in improving ability raises both the mean and the variance of the resulting ability distribution, multiple...

This paper studies a model of human capital accumulation with real wage rigidity. It is shown that the arbitrage condition between hiring a skilled versus an unskilled worker may be stated as a positive relationship between their relative unemployment rates. It may be the case that this locus is...