We examine the timing of firms' operations in a formal model of labor demand. Merging a variety of data sets from Portugal from 1995-2004, we describe temporal patterns of firms' demand for labor and estimate production-functions and relative labor-demand equations. The results demonstrate the...

The paper demonstrates the general difficulty of inferring the structure of adjustment costs from aggregated, including industry data, except in the unlikely case that costs are symmetric and quadratic at the micro level. The implications of this difficulty for cross-national comparisons of...