Specific training, unions, and the relationship between employer size and wages

In this paper I demonstrate that the explanatory power of employer size variables in nonunion wage regressions is diminished by allowing the coefficient of tenure (years on current job) to vary with employer size. Among nonunion workers, average tenure and the coefficient of tenure increase with both firm size and plant size. This pattern is consistent with the hypothesis that investment in specific human capita1 accounts for much of the previously unexplained relationship between employer size and nonunion wages . The relationships between compensation tenure, and employer size are different for union workers. Employer size is less important generally, and the importance of plant size is especially low. Also, the data are more consistent with the specific human capital model when union compensation is measured by annual income rather than the hourly wage.