We propose a theory of skill mobility across cities. It predicts the well documented city size-wage premium: the wage distribution in large cities first-order stochastically dominates that in small cities. Yet, because this premium is reflected in higher house prices, this does not necessarily...

We argue that using wage data alone, it is virtually impossible to identify whether Assortative Matching between worker and firm types is positive or negative. In standard competitive matching models the wages are determined by the marginal contribution of a worker, and the marginal contribution...