An official website of the United States government
United States Department of Labor
United States Department of Labor
The .gov means it's official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information,
make sure you're on a federal government site.
The site is secure.
The
https:// ensures that you are connecting to the official website and that any
information you provide is encrypted and transmitted securely.
Office of Survey Methods Research
SHARE ON:
More Information
Published Year: 2007
Survey/Program(s): Office of Productivity and Technology
Catalog: Economic Working Paper
WP Number: WP-404
Publication Status / Disposition: Available from the Office of Productivity and Technology (March 2007).
Download PDF
The Strength of Occupation Indicators as a Proxy for Skill
Abstract
Labor economists have long used occupation indicators as a proxy for unobserved skills that a worker possesses. In this paper, we consider whether inter-occupational wage differentials that are unexplained by measured human capital are indeed due to differences in often-unmeasured skill. Using the National Compensation Survey, a large, nationally- representative dataset on jobs and ten different components of requisite skill, we compare the effects on residual wage variation of including occupation indicators and including additional skills measures. We find that although skills do vary across 3-digit occupations, occupation indicators decrease wage residuals by far more than can be explained by skill differentials. This indicates that "controlling for occupation" does not equate to controlling for skill alone, but also for some other factors to a great extent.
Additionally, we find that there is considerable within occupation variation in skills, and that the amount of variation is not constant across skill levels. As a result, including occupation indicators in a wage model introduces heteroskedasticity that must be accounted for. We suggest that greater caution be applied when using and interpreting occupation indicators as controls in wage regressions.