The Speed of Employer Learning
首次估计了雇主了解工人生产效率的速度，发现雇主学习很快，初始预期误差在3年内下降50%，这为信号理论对教育收益的贡献设定了上限，在多数参数下信号贡献低于25%。
The employer-learning literature finds support for statistical discrimination on the basis of schooling. How economically relevant statistical discrimination is depends on how fast employers learn about workers’ productive types. This article is the first to estimate the speed of employer learning. Employers learn quickly. Initial expectation errors decline by 50% within 3 years. This estimate places an upper bound on the contribution of signaling. This bound varies with the speed of employer learning and with discount rate. For a wide range of parameter values, the contribution of signaling to the gains from schooling is less than 25%.