UNIONS, WAGES, AND SKILLS

Studies uniformly conclude that union wage effects are largest for wor kers with low measured skills. Longitudinal analysis using 1989/90-199 4/95 Current Population Survey matched panels produces union premium e stimates equivalent across skill groups, following appropriate sample restrictions and control for worker-specific skills. Evidence from the National Longitudinal Survey of Youth on aptitude scares confirms tha t union workers with high measured skills have relatively low unmeasur ed skills. Differential selection by skill class and skill homogeneity in union workplaces results from employer and employee sorting ill re sponse to wage standardization, union organizing where skills are homo geneous, and unionized employers' reluctance to hire the most as well as least able workers.