The Changing Skill Content of Private-Sector Union Coverage
研究了近半个世纪美国私营部门工会覆盖工作的技能内容变化，发现工会工作越来越需要非日常认知技能，而日常体力技能需求下降，这些变化主要由职业间工人分布和职业结构变动驱动。
Concurrent with the decline in private-sector unionization over the past half century, a shift has occurred in the type of work covered by unions. The authors take a skill-based approach to study this shift. For both men and women, private-sector unionized jobs have changed to require more non-routine, cognitive skills, and for women, less routine, manual skills. Union/non-union skill differences have grown, with unionized jobs requiring relatively more non-routine, cognitive skill and relatively more routine, manual and routine, cognitive skills. The authors decompose these changes into 1) changes in skills within an occupation, 2) changes in worker concentration across existing occupations, and 3) changes to the occupational mix from entry and exit. Most of the changes they document are driven by the second two forces. Finally, the article discusses how this evidence can be reconciled with a model of skill-biased technological change that directly accounts for the institutional framework surrounding collective bargaining.