My research interests are in the areas of labor economics and applied microeconometrics, with a special focus on the economics of issues relating to the low-income population in the U.S.. A large portion of my research in labor economics has concerned the labor supply decisions of female heads of family and its response to the U.S. welfare system. My research on the welfare system has led to publications on the AFDC, Food Stamp, and Medicaid programs. I have also published research on the labor supply and family structure effects of social insurance programs, including Social Security, unemployment insurance, and disability insurance, as well as of the U.S. income tax system. Other papers have concerned trends in volatility in the U.S. labor market and trends in the labor force attachment of men and women. Part of my research also focuses on population economics and economic demography, where I have estimated economic models of marriage, cohabitation, female headship, and fertility. My methodological research has led to publications on selection bias and limited-dependent variable models, nonlinear budget constraints, panel data, attrition, duration models, and causal modeling and program evaluation.
I am the Krieger-Eisenhower Professor of Economics at Johns Hopkins University, where I have worked since 1995. I also hold a joint appointment at the Johns Hopkins Bloomberg School of Public Health. Prior to assuming my positions at Hopkins, I was Professor of Economics at Brown University, where I taught for eleven years. I have also been a visiting professor at the University of Wisconsin and the University of Maryland, and worked for several years at Mathematica Policy Research, Inc.
I am also a Fellow of the Econometric Society, a Fellow of the Society of Labor Economists, a member of the National Academy of Sciences, a recipient of a MERIT Award from the National Institutes of Health, a recipient of a Guggenheim Fellowship, a Fellow of the American Academy of Arts and Sciences, and Past President of the Population Association of America. I have served as Chief Editor of the American Economic Review, Coeditor of the Review of Economics and Statistics, Chief Editor of the Journal of Human Resources, and as Chair of the National Academy of Sciences Panel to Evaluate Welfare Reform. I am currently editor of Tax Policy and the Economy, a publication of the National Bureau of Economic Research which provides policy analysts in Washington with results from recent academic economic research on tax and transfer issues.
“Interview with University of Chicago, December 2018”
“HCEO Video on my Welfare Program Research”
"Reconciling Trends in U.S. Male Earnings Volatility: Results from Survey and Administrative Data", (January, 2023) [PDF Copy]
"The Effect of the COVID-19 Pandemic Recession on Less Educated Women’s Human Capital: Some Projections", (November, 2022) [PDF Copy]
"Balancing Data Privacy and Usability in the Federal Statistical System", (June, 2022) [PDF Copy]
"Take-up of Social Benefits", (June, 2022) [PDF Copy]
"The Supplemental Expenditure Poverty Measure: A New Method for Measuring Poverty", (May, 2022) [PDF Copy]
"The Marginal Labor Supply Disincentives of Welfare: Evidence from Administrative Barriers to Participation", (January, 2022) [PDF Copy]
"The Return to Work in Disability Programs: What Has Been Learned and Next Steps", (December, 2021) [PDF Copy]
"Covid-19 and the U.S. Safety Net", (September, 2020) [PDF Copy]
Policy and Other Papers:
"Recent Trends in the Distribution of Social Safety Net Support: Inequality in Government Transfers", (February, 2022) [PDF Copy]
Trends in the Distribution of Social Safety Net Support After the Great Recession (February, 2018) [PDF Copy]
Unemployment Benefits and Unemployment, IZA World of Labor, 2015 [PDF Copy]
Evaluation Methods for Program Entry Effects (1992) [PDF Copy]
Trends in the Covariance Structure of Earnings in the U.S.: 1969-1987 (July 1995) [PDF Copy]
Printed in the Rediscovered Classics Series in the Journal of Economic Inequality (August, 2011)
First Year Seminar 149 -- What is Poverty
Social science is the scholarly study of society and social behavior. This First-Year Seminar will introduce students to the social sciences by studying poverty in America through the lens of economics and other social sciences, including sociology and anthropology. The quantitative approach taken by economics will be compared and contrasted with qualitative approaches. Illustrations of how the lives of the poor are led as depicted in ethnographic studies and movies will be studied to learn how integrated perspectives can be formed. Students will learn how to read scholarly articles with a critical eye, to speak about their interpretations of the material, and to write short critical essays. Students will also be introduced to quantitative analysis using graphs and tables. A short presentation on a poverty topic at the end of the semester. Guest lecturers bringing non-economics perspectives will visit the class.
Economics 651 -- Labor Economics:
This is a graduate survey course in labor economics. The course covers most of the classic topics in labor, including labor supply, labor demand, human capital, compensating wage differentials, and unemployment and job search. Reflecting the field, much of the material is empirical in nature and will use advanced econometric techniques.