Individual Heterogeneity and Interindustry Wage Differentials
利用长期面板数据估计行业间工资差异，发现84%的工资差异可由个体固定效应解释，行业效应仅解释16%，且未发现效率工资理论预测的工资刚性现象。
Estimates of interindustry wage differentials are obtained using a fixed-effects estimator on a long panel, the National Longitudinal Survey of Young Men (NLS). After controlling for observable worker characteristics, 84 percent of the residual variance of log wages across industries is by individual fixedeffects. Only 16 percent of the residual variance is explained by industry dummies. Since no controls for specific job characteristics are used, job characteristics that vary across industries could potentially explain this rather small residual across-industry log wage variance that is not attributable to individual effects. Clearly, then, these data do not force us to resort to noncompetitive explanations of interindustry wage differentials, such as efficiency wage theory. Furthermore, efficiency wage theories predict that wages in efficiency wage paying (or primary) industries should be relatively rigid. Therefore, industry wage differentials should widen in recessions. However, no such tendency is found in the data.