Positive assortative matching implies that high productivity workers and firms match together. However, there is almost no evidence of a positive correlation between the worker and firm contributions in two-way fixed-effects wage equations. This could be the result of a bias caused by standard...

In the empirical literature on the estimation of firm and worker heterogeneity using linked employer-employee data, unobserved worker quality appears to be negatively correlated with unobserved firm quality. We investigate the possibility that this is simply caused by standard estimation error...