"In this paper, we construct a simple model based on heterogeneity in workers' productivity and homogeneity in their working schedules. This simple model can generate unemployment, even if wages adjust instantaneously, firms are perfectly competitive, and firms can perfectly observe workers'...

"We analyze the volatility surface vs. moneyness and time to expiration implied by MIBO options written on the MIB30, the most important Italian stock index. We specify and fit a number of models of the implied volatility surface and find that it has a rich and interesting structure that...

This paper is an investigation into the determinants of asymmetries in stock returns. We develop a series of cross-sectional regression specifications which attempt to forecast skewness in the daily returns of individual stocks. Negative skewness is most pronounced in stocks that have...