Do Urban Agglomeration Effects and Household Amenities have a Skill Bias?*
研究城市规模对工资的影响，发现城市规模扩大时教育回报率下降，表明城市便利设施对高技能工人的影响大于生产率效应。
There are several hypotheses why urban scale affects wages. Most focus on agglomeration economies that increase labor demand, especially for high‐skilled workers (e.g., dynamic externalities stress knowledge transfers, and imply the urban wage gap favors skilled workers). Others stress urban amenities that increase labor supply and decrease wages. Amenities should have a stronger influence on affluent households if they are normal goods. By examining whether urban‐scale affects net returns to education, it can be determined whether skilled workers are influenced more by urban productivity or amenities. Empirical results suggest net returns to education decline with urban scale, implying a key role for urban amenities in affecting skilled workers.