Labor studies.

Freeman, Richard B.

Two developments have made the period since I last summarized the work of the NBER's labor program particularly exciting: first, several topics of NBER research have attracted great public attention. Rising wage inequality, the subject of many Bureau Working Papers between 1991 and 1994, is now recognized as one of the nation's major economic problems. The effect of labor market institutions and government policies--ranging from minimum wages to training--on employment and wages also has been the subject of considerable public discourse. Further, internationalization of the U.S. economy, NAFTA, and development of the Common Market all have increased the interest of business and the public in how labor markets overseas work.

Second, newly available microdatasets for firms and individuals in many countries, and continued improvements in computer technology have opened new vistas for NBER researchers. In the 1980s, most researchers exploited U.S. microdatasets, which provided information on individuals; in the 1990s, many economists have analyzed datasets from other countries, and cross-sectional and longitudinal data for firms. Now researchers are beginning to examine the "intersection" of these two forms of data: that is, longitudinal data that track the economic performance of both individual workers and the establishments in which they work.

In the early 1990s, the NBER's labor studies program focused in particular on the following areas: earnings inequality; the behavior of labor demand; the effect of government programs; training; international comparisons; and social or family effects on individuals.

Earnings Inequality(1)

Bureau studies of earnings inequality, and of the fall in the real earnings of less-skilled workers, have documented a period of rising inequality, both among and within observable skill groups, and in hours worked. What emerges in these studies is a multicausal explanation of the rise in earnings inequality: in the 1980s, and to some extent earlier, the forces of supply and demand and institutional changes all operated in the same direction to raise inequality.

On the supply side, the key factors were: 1) a reduced rate of growth in the supply of college graduates relative to less-educated workers, caused in part by young Americans' decisions about investing in education; and 2) the influx of less-educated immigrants. On the demand side, shifts toward more-educated workers within industries, shown by Alan B. Krueger to be related in part to technological changes associated with computers, and by myself, George J. Borjas, and Lawrence F. Katz to be related to the growth of the trade deficit, are widely cited factors. In terms of institutional changes, David Card, Thomas Lemieux, and I have shown that the decline in unionization and the reduction in the real value of the minimum wage contributed to the increase in inequality. Katz and Kevin M. Murphy conclude that these factors help to account for the rise in earnings differentials among workers who differ in measured skills. In addition, measured shifts in demand and supply have been shown to affect the earnings of blacks and women by John Bound and Harry J. Holzer, and by Francine D. Blau and Lawrence M. Kahn, respectively. Steven G. Allen and several others also have examined the interindustry wage structure, which is an important component of wage differences. Still, these analyses have been unable to pin down the factors underlying the rise in inequality among workers with the same measured attributes.

Labor Demand Behavior

The surge in interest in the demand for labor,(2) focused on everything from the use of outside contractors to the dynamics of adjustments in firm size and employment growth, perhaps spurred by changes in the minimum wage, has yielded some results that have challenged conventional wisdom. Daniel S. Hamermesh has developed models that explore the dynamics of demand, among other things. Steven J. Davis (and others) have shown that small employers do not create more net jobs than larger firms in the manufacturing sector, because the job destruction rate as well as the job creation rate is greater in small firms than in large firms. Eli Berman, Bound, and Zvi Griliches report that labor demand within industries has shifted toward more skilled workers, which helps to explain the rise of inequality. Bound and Holzer also have examined the effect of industrial shifts on the employment of black workers relative to white workers. And, Douglas L. Kruse has developed evidence that profit-sharing arrangements raise firm productivity.(3)

Several researchers, in particular Card, Krueger, and Katz, have examined the demand-side effects of recent increases in the minimum wage.(4) Their results are striking: they find that the recent increases have had no discernible adverse effect on employment, which raises questions about the appropriate model for analyzing modest changes in wages in the labor market for low-skilled workers.

Training and Human Capital Formation

Continuing the long NBER tradition, stretching back to the pioneering work of Gary S. Becker and Jacob A. Mincer, researchers have explored the effects of various government programs and policies on investment in schooling, earnings profiles, and human capital formation in general.(5) James J. Heckman and Steven J. Cameron have examined the effects of the widely used General Equivalency Degree, and found that it is far from the equivalent of a high school education in terms of earning power. Thomas J. Kane and Cecilia Rouse have found that two years of junior or community college earns roughly the same return as two years in a four-year college, though. Ronald G. Ehrenberg and his coauthors have studied the effects of government programs on the decision to attend college.

Finally, Card and Krueger, and Michael A. Boozer, Krueger, and Shari Wolkon have examined issues relating to school quality. Their results suggest that differences in school quality play a greater role in earnings than had been found in past studies of educational production functions.

In addition, various NBER studies used different instrumental variables to determine the effect of schooling, and examined randomized experiments to assess training programs. These papers are summarized in the methodology section of this Program Report.

Other Government Programs

In addition to studying minimum wages and training or education programs, Bureau researchers have analyzed the labor market effects of a diverse set of governmental programs.(6) Janet Currie has examined the effects of several programs, including Head Start, on the well-being of children. Jonathan Gruber and Maria J. Hanratty have explored the possible labor market effects of introducing national health insurance, Canadian-style, to the United States. Gruber also has analyzed the effects of unemployment insurance on consumption smoothing, beginning what I hope will be a series of studies on the benefits of a program whose costs, in terms of extended joblessness, have been analyzed in great detail. Rebecca M. Blank (and Patricia Ruggles) studied Aid to Families with Dependent Children. Olivia S. Mitchell has explored the U.S. retirement system. David A. Wise and coauthors have examined the interaction between Social Security and employer-provided pensions and health benefits, along with their studies of related government programs and aging. Patricia M. Anderson and Bruce D. Meyer have examined unemployment insurance benefits, while Wayne B. Gray and John Sholz studied the effects of OSHA inspections on injuries. Finally, Morris M. Kleiner and Robert T. Kudrie analyzed the effects of occupational licensing on entry into dentistry across the U.S. states.

Given the diversity of programs and analyses, it is difficult to summarize this work. Some government programs seem to have both intended and unintended effects on the labor market, while others either have little effect or an effect that is hard to determine.

International Comparisons

Some of the papers in the labor studies program dealing with foreign countries are associated with the "Working Under Different Rules" project (described in the Summer 1993 Reporter), but others were undertaken separately.(7) The range of issues is considerable. Amanda Gosling and Stephen Machin studied the effects of British unions on the dispersion of earnings in Britain. Katharine G. Abraham and Susan N. Houseman examined labor adjustments in Germany. Lemieux and Sara De La Pica investigated the grey economy in Spain, while Per-Anders Edin looked at the decline of solidarity bargaining in Sweden. David G. Blanchflower and Lisa M. Lynch studied on-the-job training in the United Kingdom, while Blanch-flower and I investigated the effects of the policies of the Thatcher government on the British labor market.

Most of these studies focused on particular countries, usually comparing them to the United States, but some took a broader approach, looking at several countries at once. Unlike traditional cross-country comparisons, almost all of the studies use detailed microdatasets to explore differences or similarities in countries, rather than using aggregate data. In one of the first uses of microdata that match workers and firms over time, John M. Abowd and Francis Kramarz examined incentive compensation within French firms.

The major message from the international comparative work is that there are different ways for capitalist economies to organize their labor markets. Some developments in the United States are found in other countries; others seem unique to the United States, raising important questions about the role of institutions in influencing labor market outcomes.

Social Capital and Institutions

Standard empirical work that focuses on individuals almost always fails to explain the full extent of economic behavior. Researchers in the labor studies program have dealt with this shortfall in various ways.(8) Some have been concerned with spillovers or externalities. In this vein, Katz and Ann C. Case used the Boston Youth Survey to provide evidence on the effects of neighborhoods; Borjas looked at spillovers related to ethnicity, while also continuing his work on immigration. Card, Edward L. Glaeser, and David C. Mare all have examined the links between labor skills and the geographic areas in which those skills are employed. Other researchers have focused on the way particular institutions operate. For example, Henry S. Farber has examined dispute resolution in cases of medical malpractice, while Orley C. Ashenfelter and David E. Bloom have studied the role of lawyers in dispute settlement.

Methodology

NBER researchers also have continued to refine the statistical tools needed to examine data, have developed imaginative "pseudo-experiments" to tease behavioral or causal inferences from nonexperimental data, and have examined the underlying quality of the available data. For example, they have explored the strengths and weaknesses of instrumental variables in obtaining behavioral or structural parameters.(9) In some of the studies, the instruments are quite ingenious: Joshua D. Angrist and Krueger use the Vietnam-era draft lottery; Ashenfelter and David J. Zimmerman, and Krueger use sibling data; and so on.(10) Others, including James J. Heckman, have been particularly innovative in exploring the value of random assignment controlled experiments.(11)

If there is a single overriding theme that emerges from the methodological papers, it is that problems exist with forms of empirical analysis and techniques that many had hoped would be "panaceas," such as instrumental variables or randomized treatments in social experiments. Methodological advances are not reducing the demand for econometricians, it seems.

Where Are Theory . . . And Plant Visits?

Labor economics is first and foremost an empirical area, and new data and technology have opened the door to analyses that researchers of previous generations would scarcely believe. Thus, it is no surprise that most work in the NBER's labor studies program is blatantly empirical, in the Bureau tradition of Simon Kuznets, albeit with computers doing the dirty work. Studies based on datasets with thousands or hundreds of thousands of observations allow researchers to establish facts in ways never before possible.

Concentration on empiricism has left two noticeable gaps in the work: 1) in the development of theory, although some researchers have sought to develop theoretical insights into various forms of behavior,(12) and most build their empirical work on microeconomic foundations; and 2) in first-hand observation of firms and workers, although some researchers make "field visits" to firms, unions, or public training programs, and most are aware that there is a world outside of their computer. I hope that my next report will tell you that the labor studies program has made some progress in amalgamating theory and case studies.

In the notes that follow, except where indicated otherwise, the number following "No." is the number of an NBER Working Paper.

1 Among the papers on inequality are: L. F. Katz and A. B. Krueger, "Changes in the Structure of Wages in the Public and Private Sectors," No. 3667, March 1991; A. H. Beller and F. D. Blau, "Black-White Earnings Over the 1970s and 1980s: Gender Differences in Trends," No. 3736, June 1991; G. J. Borjas, R. B. Freeman, and L. F. Katz, "On the Labor Market Effects of Immigration and Trade," No. 3761, June 1991; J. Bound and R. B. Freeman, "What Went Wrong? The Erosion of Relative Earnings and Employment Among Young Black Men in the 1980s," No. 3778, July 1991; G. J. Borjas, "Ethnic Capital and Intergenerational Mobility," No. 3788, July 1991; C. Goldin and R. A. Margo, "The Great Compression: The Wage Structure in the United States at Midcentury," No. 3817, August 1991; R. B. Freeman, "How Much Has Deunionization Contributed to the Rise in Male Earnings Inequality?" No. 3826, August 1991; R. B. Freeman and K. Needels, "Skill Differentials in Canada in an Era of Rising Labor Market Inequality," No. 3827, September 1991; A. B. Krueger, "How Computers Have Changed the Wage Structure: Evidence from Microdata, 1984-9," No. 3858, October 1991; M. L. Blackburn, D. E. Bloom, and R. B. Freeman, "Changes in Earnings Differentials in the 1980s: Concordance, Convergence, Causes, and Consequences," No. 3901, November 1991; L. F. Katz and K. M. Murphy, "Changes in Relative Wages, 1963-87: Supply-and-Demand Factors," No. 3927, December 1991; D. M. Cutler and L. F. Katz, "Rising Inequality? Changes in the Distribution of Income and Consumption in the 1980s," No. 3964, January 1992; D. E. Bloom and R. B. Freeman, "The Fall in Private Pension Coverage in the United States," No. 3973, January 1992; S. J. Davis, "Cross-Country Patterns of Change in Relative Wages," No. 4085, June 1992; F. D. Blau and L. M. Kahn, "Race and Gender Pay Differentials," No. 4120, July 1992; D. Card, "The Effect of Unions on the Distribution of Wages: Redistribution or Relabeling?" No. 4195, October 1992; D. R. Feenberg and J. M. Poterba, "Income Inequality and the Incomes of Very High Income Taxpayers: Evidence from Tax Returns," NBER Reprint No. 1797, June 1993; D. Card and T. Lemieux, "Wage Dispersion, Returns to Skill, and Black-White Wage Differentials," No. 4365, May 1993; G. J. Borjas and V. A. Ramey, "Foreign Competition, Market Power, and Wage Inequality: Theory and Evidence," No. 4556, December 1993; D. E. Bloom and G. Grenier, "Language, Employment, and Earnings in the United States: Spanish-English Differentials from 1970 to 1990," No. 4584, December 1993; C. Juhn, "Wage Inequality and Industrial Change: Evidence from Five Decades," No. 4684, March 1994; J. M. Constantine and D. Neumark, "Training and the Growth of Wage Inequality," No. 4729, May 1994; F. D. Blau and L. M. Kahn, "The Impact of Wage Structure on Trends in U.S. Gender Wage Differentials, 1975-87," No. 4748, May 1994; D. Card and T. Lemieux, "Changing Wage Structure and Black-White Wage Differentials Among Men and Women: A Longitudinal Analysis," No. 4755, May 1994; S. J. Davis and J. C. Haltiwanger, "Gross Job Creation, Gross Job Destruction, and Employment Reallocation," No. 3728, June 1991; G. J. Borjas, "Long-Run Convergence of Ethnic Skill Differentials," No. 4641, February 1994; J. G. Altonji and T. A. Dunn, "Relationships Among the Family Incomes and Labor Market Outcomes of Relatives," No. 3724, June 1991; and S. G. Allen "Updated Notes on the Interindustry Wage Structure, "No. 4664, February 1994.

2 The following papers examine demand issues: D. S. Hamermesh, "Labor Demand: What Do We Know? What Don't We Know?" No. 3890, November 1991; J. B. Rebitzer and L. J. Taylor, "Do Labor Markets Provide Enough Short-Hour Jobs? An Analysis of Work Hours and Work Incentives," No. 3883, October 1991; D. S. Hamermesh, W. H. J. Hassink, and J. C. van Ours, "New Facts About Factor-Demand Dynamics: Employment, Jobs, and Workers," No. 4625, January 1994; J. B. Rebitzer and L. J. Taylor, "Work Incentives and the Demand for Primary and Contingent Labor," No. 3647 March 1991; D. S. Hamermesh and G. Pfann, "Turnover and the Dynamics of Labor Demand," No. 4204, October 1992; D. S. Hamermesh, "Labor Demand and the Source of Adjustment Costs," No. 4394, July 1993; S. J. Davis. J. C. Haltiwanger, and S. Schuh, "Small Business and Job Creation: Dissecting the Myth and Reassessing the Facts," No. 4492, October 1993; K. G. Abraham and S. K. Taylor, "Firms' Use of Outside Contractors: Theory and Evidence," No. 4468, September 1993; D. Card and A. B. Krueger, "Minimum Wages and Employment: A Case Study of the Fast Food Industry in New Jersey and Pennsylvania," No. 4509, October 1993; and S. N. Houseman and K. G. Abraham, "Labor Adjustment Under Different Institutional Structures: A Case Study of Germany and the United States, "No. 4548, November 1993.

3 D. L. Kruse, "Does Profit Sharing Affect Productivity?" No. 4542, November 1993.

4 The following papers explore the effects of the minimum wage: L. F. Katz and A. B. Krueger, "The Effect of the New Minimum Wage Law in a Low-Wage Labor Market," No. 3655, March 1991; D. Card, "Do Minimum Wages Reduce Employment? A Case Study of California, 1987-9," No. 3710, May 1991; A. C. Freeman and R. B. Freeman, "Minimum Wages in Puerto Rico: Textbook Case of a Wage Floor?" No. 3759, June 1991; D. Neumark and W. Wascher, "Evidence on Employment Effects of Minimum Wages and Subminimum Wage Provisions from Panel Data on State Minimum Wage Laws, "No. 3859, October 1991; J. B. Rebitzer and L. J. Taylor, "The Consequences of Minimum Wage Laws: Some New Theoretical Ideas," No. 3877, October 1991; L. F. Katz and A. B. Krueger, "The Effect of the Minimum Wage on the Fast Food Industry," No. 3997 February 1992; D. Card, "Using Regional Variation in Wages to Measure the Effects of the Federal Minimum Wage," No. 4058, April 1992; J. Currie and B. Fallick, "A Note on the New Minimum Wage Research," No. 4348, April 1993; D. Card, L. F. Katz, and A. B. Krueger, "An Evaluation of Recent Evidence on the Employment Effects of Minimum and Subminimum Wages," No. 4528, November 1993; D. Neumark and W. Wascher, "Employment Effects of Minimum and Subminimum Wages: Reply to Card, Katz, and Krueger," No. 4570, December 1993; and A. B. Krueger, "The Effect of the Minimum Wage When It Really Bites: A Reexamination of the Evidence from Puerto Rico," No. 4757, June 1994.

5 Among the papers in this area are: S. J. Cameron and J. J. Heckman, "The Non-equivalence of High School Equivalents," No. 3804, August 1991; D. J. Brewer, R. G. Ehrenberg, and D. I. Rees, "How Would Universities Respond to Increased Federal Support for Graduate Students?" NBER Reprint No. 1795, June 1993; R. G. Ehrenberg and P. G. Mavros, "Do Doctoral Students' Financial Support Patterns Affect Their Times-to-Degree and Completion Probabilities?" No. 4070, May 1992; R. G. Ehrenberg, D. D. Goldhaber, and D. J. Brewer, "Do Teachers' Race, Gender, and Ethnicity Matter? Evidence from NELS88," No. 4669, March 1994; M. A. Boozer, A. B. Krueger, and S. Wolkon, "Race and School Quality since Brown vs. Board of Education," No. 4109, June 1992; D. Card, "Using Geographic Variation in College Proximity to Estimate the Return to Schooling," No. 4483, October 1993; T. J. Kane and C. Rome, "Labor Market Returns to Two- and Four-Year Colleges: Is a Credit a Credit, and Do Degrees Matter?" No. 4268, January 1993; J. Tracy and J. Waldfogel, "The Best Business Schools: A Market-Based Approach," No. 4609, January 1994; E. L. Glaeser and D. C. Mare, "Cities and Skills," No. 4728, May 1994; V. R. Fuchs and D. M. Reklis, "Mathematical Achievement in Eighth Grade: Interstate and Racial Differences," No. 4784, June 1994; M. L. Blackburn and D. Neumark, "Are OLS Estimates of the Return to Schooling Biased Downward? Another Look," No. 4259, January 1993; D. Neumark and P. J. Taubman, "Why Do Wage Profiles Slope Upwards? Tests of the General Human Capital Model," No. 4688, March 1994; and D. Card and A. B. Krueger, "School Quality and Black-White Relative Earnings: A Direct Assessment," No. 3713, May 1991.

6 Among the papers in this area are: W. B. Gray and J. T. Scholz, "Do OSHA Inspections Reduce Injuries? A Panel Analysis," No. 3774, July 1991; N. Cole and J. Currie, "Does Participation in Transfer Program During Pregnancy Improve Birthweight?" No. 3832, September 1991; J. Currie, L. Nixon, and N. Cole, "Restrictions on Medicaid Funding of Abortion: Effects on Pregnancy Resolutions and Birthweight, "No. 4432, August 1993; A. P. Bartel, "Productivity Gains from the Implementation of Employee Training Programs," No. 3893, November 1991; J. Currie and S. McConnell, "The Impact of Collective Bargaining Legislation on Disputes in the U.S. Public Sector: No Policy May Be the Worst Policy," No. 3978, January 1992; D. Card and P. B. Levine, "Unemployment Insurance Taxes and the Cyclical and Seasonal Properties of Unemployment," No. 4030, March 1992; O. S. Mitchell and R. S. Smith, "Pension Funding in the Public Sector," No. 3898, November 1991; J. Gruber and M. J. Hanratty, "The Labor Market Effects of Introducing National Health Insurance: Evidence from Cana-da," No. 4589, December 1993; J. C. Ham and R. LaLonde, "Estimating the Effect of Training on Employment and Unemployment Durations: Evidence from Experimental Data," No. 3912, November 1991; M. M. Kleiner and R. T. Kudrie, "Do Tougher Licensing Provisions Limit Occupational Entry? The Case of Dentistry," No. 3984, February 1992; R. G. Ehrenberg and D. J. Brewer, "Did Teachers' Race and Verbal Ability Matter in the 1960s? Coleman Revisited," No. 4293, March 1993; R. M. Blank and R. B. Freeman, "Evaluating the Connection Between Social Protection and Economic Flexibility," No. 4338, April 1993; J. Gruber and B. C. Madrian, "Limited Insurance Portability and Job Mobility: The Effects of Public Policy on Job-Lock," No. 4479, September 1993; J. J. Heckman, "Assessing Clinton's Program on Job Training, Workfare, and Education in the Workplace," No. 4428, August 1993; R. L. Lumsdaine, J. H. Stock, and D. A. Wise, "Retirement Incentives: The Interaction Between Employer-Provided Provisions, Social Security, and Retiree Health Benefits," No. 4613, January 1994; R. M. Blank and P. Ruggles, "When Do Women Use AFDC and Food Stamps?" The Dynamics of Eligibility Versus Participation," No. 4429, August 1993; and P. M. Anderson and B. D. Meyer, "Unemployment Insurance Benefits and Take-up Rates, "No. 4787, June 1994.

7 Among the papers dealing with labor markets in other countries are: M. L. Blackburn and D. E. Bloom, "The Distribution of Family Income: Measuring and Explaining Changes in the 1980s for Canada and the United States," No. 3659, March 1991; D. E. Bloom and G. Grenier, "The Earnings of Linguistic Minorities: French in Canada and Spanish in the United States," No. 3660, March 1991; G. J. Borjas, "Immigration Policy, National Origin, and Immigrant Skills: A Comparison of Canada and the United States, "No. 3691, April 1991; M. L. Blackburn and D. Neumark, "Omitted-Ability Bias and the Increase in the Return to Schooling," No. 3693, May 1991; J. M. Abowd and T. Lemieux, "The Effects of Product Market Competition on Collective Bargaining Agreements: The Case of Foreign Competition in Canada," No. 3808, August 1991; D. G. Blanchflower and L. M. Lynch, "Training at Work: A Comparison of U.S. and British Youths, "No. 4037, March 1992; J. M. Abowd and F. Kramarz, "A Test of Negotiation and Incentive Compensation Models Using Longitudinal French Enterprise Data," No. 4044, April 1992; D. G. Blanchflower and A. J. Oswald, "International Wage Curves, "No. 4200, October 1992; A. B. Krueger and J.-S. Pischke, "A Comparative Analysis of East and West German Labor Markets: Before and After Unification," No. 4154, August 1992; R. B. Freeman, "What Direction for Labor Market Institutions in Eastern and Central Europe?" No. 4209, November 1992; F. D. Blau and L. M. Kahn, "The Gender Earnings Gap: Some International Evidence," No. 4224, December 1992; D. G. Blanchflower and A. J. Oswald, "Entrepreneurship, Happiness, and Supernormal Returns: Evidence from Britain and the United States, "No. 4228, December 1992; P.-A. Edin and B. Holmlund, "The Swedish Wage Structure: The Rise and Fall of Solidarity Wage Policy?" No. 4257, January 1993; L. F. Katz, G. W. Loveman, and D. G. Blanchflower, "A Comparison of Changes in the Structure of Wages in Four OECD Countries, "No. 4297, March 1993; D. Holtz-Eakin, "Health Insurance Provision and Labor Market Efficiency in the United States and Germany, "No. 4388, June 1993; D. G. Blanchflower and R. B. Freeman, "Did the Thatcher Reforms Change British Labor Performance?" No. 4384, June 1993; K. G. Abraham and S. N. Houseman, "Does Employment Protection Inhibit Labor Market Flexibility? Lessons from Germany, France, and Belgium," No. 4.390, June 1993; S. D. L. Rica and T. Lemieux, "Does Public Health Insurance Reduce Labor Market Flexibility or Encourage the Underground Economy? Evidence from Spain and the United States," No. 4402, July 1993; E. B. Montgomery, "Patterns in Regional Labor Market Adjustment: The United States Versus Japan," No. 4414, August 1993; O. S. Mitchell, "Retirement Systems in Developed and Developing Countries: Institutional Features, Economic Effects, and Lessons for Economies in Transition," No. 4424, August 1993; R. B. Freeman and R. S. Gibbons, "Getting Together and Breaking Apart: The Decline of Centralized Collective Bargaining," No. 4464, September 1993; D. Harhoff and T. J. Kane, "Financing Apprenticeship Training: Evidence from Germany," No. 4557, December 1993; D. E. Bloom, G. Grenier, and M. Gunderson, "The Changing Labor Market Position of Canadian Immigrants," No. 4672, March 1994; F. D. Blau and L. M. Kahn, "International Differences in Male Wage Inequality: Institutions Versus Market Force," No. 4678, March 1994; A. Gosling and S. Machin, "Trade Unions and the Dispersion of Earnings in British Establishments, 1980-90," No. 4732, May 1994; R. Disney, A. Gosling, and S. Machin, "British Unions in Decline: An Examination of the 1980s Fall in Trade Union Recognition," No. 4733, May 1994; D. G. Blanchflower and R. B. Freeman, "The Legacy of Communist Labor Relations, "No. 4740, May 1994; D. G. Blanchflower and A. J. Oswald, "Estimating a Wage Curve for Britain, 1973-90," No. 4770, June 1994; M. L. Blackburn and D. E. Bloom, "Changes in the Structure of Family Income Inequality in the United States and Other Industrial Nations During the 1980s," No. 4754, May 1994; A. Forslund and A. B. Krueger, "An Evaluation of the Swedish Active Labor Market Policy: New and Received Wisdom," No. 4802, July 1994; and D. S. Hamermesh, "Policy Transferability and Hysteresis: Daily and Weekly Hours in the BRD and the United States," No. 4773, June 1994.

8 Among the papers here are: A. T. Geronimus and S. Korenman, "The Socioeconomic Consequences of Teen Childbearing Reconsidered," No. 3701, May 1991; A. C. Case and L. F. Katz, "The Company You Keep: The Effects of Family and Neighborhood on Disadvantaged Youths," No. 3705, May 1991; J. M. Kang, T. Yamada, and T. Yamada, "Crime Rates Versus Labor Market Conditions: Theory and Time-Series Evidence," No. 3801, August 1991; R. B. Freeman, "Crime and the Employment of Disadvantaged Youths," No. 3875, October 1991; J. Mullahy and J. L. Sindelar, "Alcoholism, Work, and Income Over the Life Cycle," NBER Reprint No. 1852, February 1994; G. J. Borjas and S. J. Trejo, "National Origin and Immigrant Welfare Recipiency," No. 4029, March 1992; J. Currie and D. Thomas, "Does Head Start Make a Difference?" No. 4406, July 1993; S. Boggess and J. Bound, "Did Criminal Activity Increase During the 1980s? Comparisons Across Data Sources, "No. 4431, August 1993; T. Yamada and T. Yamada, "The Allocation of Time: Young Versus Elderly Households in Japan," No. 4386, June 1993; J. Currie, "Rules, Coordination, and Manipulability Among Arbitrators," No. 3821, August 1991; H. S. Farber and M. J. White, "A Comparison of Formal and Informal Dispute Resolution in Medical Malpractice," No. 4371, May 1993; O. C. Ashenfelter and D. E. Bloom, "Lawyers as Agents of the Devil in a Prisoner's Dilemma Game," No. 4447, September 1993; G. J. Borjas, "Long-Run Convergence of Ethnic Skill Differentials," No. 4641, February 1994; C. R. Hulten, "The Intergenerational Mobility of Immigrants," No. 3972, January 1992; G. J. Borjas, "Ethnic Capital and Intergenerational Mobility," No. 3788, July 1991; and G. J. Borjas and S. J. Trejo, "Immigrant Participation in the Welfare System, "NBER Reprint No. 1600, September 1991.

9 J. D. Angrist, G. W. Imbens, and D. B. Rubin, "Identification of Causal Effects Using Instrumental Variables," NBER Technical Paper No. 136, June 1993; and J. Bound, D. A. Jaeger, and R. Baker, "The Cure Can Be Worse Than the Disease: A Cautionary Tale Regarding Instrumental Variables," NBER Technical Paper No. 137, June 1993.

10 D. Neumark, "Biases in Twin Estimates of the Return to Schooling: A Note on Recent Research," NBER Technical Paper No. 158, June 1994; O. C. Ashenfelter and D. J. Zimmerman, "Estimates of the Returns to Schooling from Sibling Data: Fathers, Sons, and Brothers," No. 4491, October 1993; J. D. Angrist and A. B. Krueger, "Estimating the Payoff to Schooling Using the Vietnam-Era Draft Lottery," No. 4067, May 1992; and O. C. Ashenfelter and A. B. Krueger, "Estimating the Economic Return to Schooling from a New Sample of Twins, "No. 4143, August 1992.

11 J. J. Heckman, "Randomization and Social Policy Evaluation," NBER Technical Paper No. 107, July 1991; J. D. Angrist and G. W. Imbens, "Sources of Identifying Information in Evaluation Models," NBER Technical Paper No. 117, December 1991, and "Identification and Estimation of Local Average Treatment Effects, "NBER Technical Paper No. 118, December 1991; C. F. Manski, "The Mixing Problem in Program Evaluation, "NBER Technical Paper No. 148, December 1993; and N. Clements, J. J. Heckman, and J. Smith, "Making the Most Out of Social Experiments: Reducing the Intrinsic Uncertainty in Evidence from Randomized Trials with an Application to the National JTPA Experiment," NBER Technical Paper No. 149, January 1994.

12 Among the papers here are: R. S. Gibbons and K. J. Murphy, "Optimal Incentive Contracts in the Presence of Career Concerns: Theory and Evidence, "NBER Reprint No. 1746, September 1992; C. Prendergast and R. H. Topel, "Favoritism in Organizations," No. 4427, August 1993; G. Baker, R. S. Gibbons, and K. J. Murphy, "Subjective Performance Measures in Optimal Incentive Contracts," No. 4480, September 1993; K. Lang and W. T. Dickens, "Bilateral Search as an Explanation for Labor Market Segmentation and Other Anomalies," No. 4461, September 1993; H. S. Farber and R. S. Gibbons, "Learning and Wage Dynamics," No. 3764, July 1991; R. B. Freeman and R. S. Gibbons, "Getting Together and Breaking Apart: The Decline of Centralized Collective Bargaining," No. 4464, September 1993; and W. T. Dickens and K. Lang, "Labor Market Segmentation Theory: Reconsidering the Evidence," No. 4087, June 1992.