Gueorgui Kambourov

Occupational Specificity of Human Capital

We find that returns to occupational tenure are substantial. Everything else being constant, 5 years of occupational tenure are associated with an increase in wages of 12%-20%. Moreover, when occupational experience is taken into account, tenure with an industry or employer has relatively little importance in accounting for the wage one receives. This finding is consistent with human capital being occupation specific. Copyright

Rising Occupational and Industry Mobility in the United States: 1968-97

We analyze the dynamics of worker mobility in the United States over the 1968-1993 period at various levels of occupational and industry aggregation. We find a substantial overall increase in occupational and industry mobility over the period and document the levels and time trends in mobility for various age-education subgroups of the population. To control for measurement error in occupation and industry coding, we develop a method that utilizes the newly released, by the Panel Study of Income Dynamics, Retrospective Occupation-Industry Supplemental Data Files. We emphasize the importance of the findings for understanding a number of issues in macro and labor economics, including changes in wage inequality, productivity, life-cycle earnings profiles, job stability and job security.

A CAUTIONARY NOTE ON USING (MARCH) CURRENT POPULATION SURVEY AND PANEL STUDY OF INCOME DYNAMICS DATA TO STUDY WORKER MOBILITY

The monthly Current Population Survey (CPS), with its annual demographic March supplement, and the Panel Study of Income Dynamics (PSID) are the leading sources of data on worker reallocation across occupations, industries, and firms. Much of the active current research is based on these data. In this paper, we contrast these data sets as sources of data for measuring the dynamics of worker mobility. We find that (i) (March) CPS data are characterized by a substantial amount of noise when it comes to identifying occupational and industry switches; (ii) March CPS data provide a poor measure of annual occupational mobility and, instead, most likely measure mobility over a much shorter period; (iii) (the changes in) the procedure to impute missing data have a dramatic effect on the interpretation of the CPS data in, e.g., the trend in occupational mobility. The most important shortcomings of the PSID are the facts that (i) occupational and industry affiliation data are available in most years at an annual frequency; (ii) the PSIDs sample, by design, excludes immigrants arriving in the United States after 1968; (iii) the Retrospective Occupation–Industry Files with reliable occupation and industry affiliation data are available only until 1980.

Occupational Mobility and Wage Inequality, Second Version

In this study we argue that wage inequality and occupational mobility are intimately related. We are motivated by our empirical findings that human capital is occupation-specific and that the fraction of workers switching occupations in the United States was as high as 16% a year in the early 1970s and had increased to 19% by the early 1990s. We develop a general equilibrium model with occupation-specific human capital and heterogeneous experience levels within occupations. We argue that the increase in occupational mobility was due to the increase in the variability of productivity shocks to occupations. The model, calibrated to match the increase in occupational mobility, accounts for over 90% of the increase in wage inequality over the period. A distinguishing feature of the theory is that it accounts for changes in within-group wage inequality and the increase in the variability of transitory earnings.

Chapter 6 Families and Careers

We study trends in occupational and geographic mobility of single and married men and women in the United States over the last 40 years. We find that while occupational mobility has increased for almost all subgroups of males, most of the increase was accounted for by a sharp increase in the mobility of singles. Similarly, the rates of geographic mobility were virtually identical for single and married workers in the early 1970s, but diverged since then – the increase in the geographic mobility of single men was more pronounced than the increase for married men. We discuss several theories of worker mobility in light of these trends and suggest that the increased labor force attachment of women might have played a prominent role in driving these changes.

Complex-Task Biased Technological Change and the Labor Market

In this paper we study the relationship between task complexity and the occupational wage- and employment structure. Complex tasks are defined as those requiring higher-order skills, such as the ability to abstract, solve problems, make decisions, or communicate effectively. We measure the task complexity of an occupation by performing Principal Component Analysis on a broad set of occupational descriptors in the Occupational Information Network (O*NET) data. We establish four main empirical facts for the U.S. over the 1980-2005 time period that are robust to the inclusion of a detailed set of controls, subsamples, and levels of aggregation: (1) There is a positive relationship across occupations between task complexity and wages and wage growth; (2) Conditional on task complexity, routine-intensity of an occupation is not a significant predictor of wage growth and wage levels; (3) Labor has reallocated from less complex to more complex occupations over time; (4) Within groups of occupations with similar task complexity labor has reallocated to non-routine occupations over time. We then formulate a model of Complex-Task Biased Technological Change with heterogeneous skills and show analytically that it can rationalize these facts. We conclude that workers in non-routine occupations with low ability of solving complex tasks are not shielded from the labor market effects of automatization.

Does Automation Drive the Labor Market

In this note we question the emerging view that automation is a primary driver of wage and employment outcomes in labor markets.