IZA - Institute of Labor Economics

Abstract Propensity score matching (PSM) has become a popular approach to estimate causal treatment effects. It is widely applied when evaluating labour market policies, but empirical examples can be found in very diverse fields of study. Once the researcher has decided to use PSM, he is confronted with a lot of questions regarding its implementation. To begin with, a first decision has to be made concerning the estimation of the propensity score. Following that one has to decide which matching algorithm to choose and determine the region of common support. Subsequently, the matching quality has to be assessed and treatment effects and their standard errors have to be estimated. Furthermore, questions like ‘what to do if there is choice‐based sampling?’ or ‘when to measure effects?’ can be important in empirical studies. Finally, one might also want to test the sensitivity of estimated treatment effects with respect to unobserved heterogeneity or failure of the common support condition. Each implementation step involves a lot of decisions and different approaches can be thought of. The aim of this paper is to discuss these implementation issues and give some guidance to researchers who want to use PSM for evaluation purposes.

This paper analyzes compensation schemes which pay according to an individual's ordinal rank in an organization rather than his output level. When workers are risk neutral, it is shown that wages based upon rank induce the same efficient allocation of resources as an incentive reward scheme based on individual output levels. Under some circumstances, risk-averse workers actually prefer to be paid on the basis of rank. In addition, if workers are heterogeneous inability, low-quality workers attempt to contaminate high-quality firms, resulting in adverse selection. However, if ability is known in advance, a competitive handicapping structure exists which allows all workers to compete efficiently in the same organization.

We investigate conditions sufficient for identification of average treatment effects using instrumental variables. First we show that the existence of valid instruments is not sufficient to identify any meaningful average treatment effect. We then establish that the combination of an instrument and a condition on the relation between the instrument and the participation status is sufficient for identification of a local average treatment effect for those who can be induced to change their participation status by changing the value of the instrument. Finally we derive the probability limit of the standard IV estimator under these conditions. It is seen to be a weighted average of local average treatment effects.

My focus is on the degree to which increasing inequality in the high-income countries, particularly in the United States, is likely to limit economic mobility for the next generation of young adults. I discuss the underlying drivers of opportunity that generate the relationship between inequality and intergenerational mobility. The goal is to explain why America differs from other countries, how intergenerational mobility will change in an era of higher inequality, and how the process is different for the top 1 percent. I begin by presenting evidence that countries with more inequality at one point in time also experience less earnings mobility across the generations, a relationship that has been called “The Great Gatsby Curve.” The interaction between families, labor markets, and public policies all structure a child's opportunities and determine the extent to which adult earnings are related to family background—but they do so in different ways across national contexts. Both cross-country comparisons and the underlying trends suggest that these drivers are all configured most likely to lower, or at least not raise, the degree of intergenerational earnings mobility for the next generation of Americans coming of age in a more polarized labor market. This trend will likely continue unless there are changes in public policy that promote the human capital of children in a way that offers relatively greater benefits to the relatively disadvantaged.

This paper examines the effect of skill-biased technological change as measured by computerization on the recent widening of U. S. educational wage differentials. An analysis of aggregate changes in the relative supplies and wages of workers by education from 1940 to 1996 indicates strong and persistent growth in relative demand favoring college graduates. Rapid skill upgrading within detailed industries accounts for most of the growth in the relative demand for college workers, particularly since 1970. Analyses of four data sets indicate that the rate of skill upgrading has been greater in more computer-intensive industries.

This article studies the global variation in economic preferences. For this purpose, we present the Global Preference Survey (GPS), an experimentally validated survey data set of time preference, risk preference, positive and negative reciprocity, altruism, and trust from 80,000 people in 76 countries. The data reveal substantial heterogeneity in preferences across countries, but even larger within-country heterogeneity. Across individuals, preferences vary with age, gender, and cognitive ability, yet these relationships appear partly country specific. At the country level, the data reveal correlations between preferences and biogeo-graphic and cultural variables, such as agricultural suitability, language structure, and religion. Variation in preferences is also correlated with economic outcomes and behaviors. Within countries and subnational regions, preferences are linked to individual savings decisions, labormarket choices, and prosocial behaviors. Across countries, preferences vary with aggregate outcomes ranging from per capita income, to entrepreneurial activities, to the frequency of armed conflicts.

This paper studies the links between productivity, innovation and research at the firm level. We introduce three new features: (i) A structural model that explains productivity by innovation output, and innovation output by research investment: (ii) New data on French manufacturing firms, including the number of European patents and the percentage share of innovative sales, as well as firm-level demand pull and technology push indicators; (iii) Econometric methods which correct for selectivity and simultaneity biases and take into account the statistical features of the available data: only a small proportion of firms engage in research activities and/or apply for patents; productivity, innovation and research are endogenously determined; research investment and capital are truncated variables, patents are count data and innovative sales are interval data. We find that using the more widespread methods, and the more usual data and model specification, may lead to sensibly different estimates. We find in particular that simultaneity tends to interact with selectivity, and that both sources of biases must be taken into account together. However our main results are consistent with many of the stylized facts of the empirical literature. The probability of engaging in research (R&D) for a firm increases with its size (number of employees), its market share and diversification, and with the demand pull and technology push indicators. The research effort (R&D capital intensity) of a firm engaged in research increases with the same variables, except for size (its research capital being strictly proportional to size). The firm innovation output, as measured by patent numbers or innovative sales, rises with its research effort and with the demand pull and technology indicators, either directly or indirectly through their effects on research. Finally, firm productivity correlates positively with a higher innovation output, even when controlling for the skill composition of labor as well as for physical capital intensity.

This article examines to what extent recent empirical evidence can collectively and systematically substantiate the claim that entrepreneurship has important economic value. Hence, a systematic review is provided that answers the question: What is the contribution of entrepreneurs to the economy in comparison to non-entrepreneurs? We study the relative contribution of entrepreneurs to the economy based on four measures that have most widely been studied empirically. Hence, we answer the question: What is the contribution of entrepreneurs to (i) employment generation and dynamics, (ii) innovation, and (iii) productivity and growth, relative to the contributions of the entrepreneurs’ counterparts, i.e., the ‘control group’? A fourth type of contribution studied is the role of entrepreneurship in increasing individuals’ utility levels. Based on 57 recent studies of high quality that contain 87 relevant separate analyses, we conclude that entrepreneurs have a very important—but specific—function in the economy. They engender relatively much employment creation, productivity growth and produce and commercialize high-quality innovations. They are more satisfied than employees. More importantly, recent studies show that entrepreneurial firms produce important spillovers that affect regional employment growth rates of all companies in the region in the long run. However, the counterparts cannot be missed either as they account for a relatively high value of GDP, a less volatile and more secure labor market, higher paid jobs and a greater number of innovations and they have a more active role in the adoption of innovations.

We look for evidence of habituation in twenty waves of German panel data: do individuals tend to return to some baseline level of well‐being after life and labour market events? Although the strongest life satisfaction effect is often at the time of the event, we find significant lag and lead effects. We cannot reject the hypothesis of complete adaptation to marriage, divorce, widowhood, birth of child and layoff. However, there is little evidence of adaptation to unemployment for men. Men are somewhat more affected by labour market events (unemployment and layoffs) than are women but in general the patterns of anticipation and adaptation are remarkably similar by sex.

We analyze the consequences of control on motivation in an experimental principal-agent game, where the principal can control the agent by implementing a minimum performance requirement before the agent chooses a productive activity. Our results show that control entails hidden costs since most agents reduce their performance as a response to the principal's controlling decision. Overall, the effect of control on the principal's payoff is nonmonotonic. When asked for their emotional perception of control, most agents who react negatively say that they perceive the controlling decision as a signal of distrust and a limitation of their choice autonomy.

Recent theories endogenize the attitude endowments of individuals, assuming that they are shaped by the attitudes of parents and other role models. This paper tests empirically for the relevance of three aspects of the attitude transmission process highlighted in this theoretical literature: (1) transmission of attitudes from parents to children; (2) an impact of prevailing attitudes in the local environment on child attitudes; and (3) positive assortative mating of parents, which enhances the ability of a parent to pass on his or her attitudes to the child. We focus on two fundamentally important attitudes, willingness to take risks and willingness to trust others. We find empirical support for all three aspects, providing an empirical underpinning for the literature. An investigation of underlying mechanisms shows that socialization is important in the transmission process. Various parental characteristics and aspects of family structure are found to strengthen the socialization process, with implications for modeling the socialization production function and for policies focused on affecting children's non-cognitive skills. The paper also provides evidence that the transmission of risk and trust attitudes affects a wide variety of child outcomes, implying a potentially large total effect on children's economic situation.

Laboratory experiments are a widely used methodology for advancing causal knowledge in the physical and life sciences. With the exception of psychology, the adoption of laboratory experiments has been much slower in the social sciences, although during the past two decades the use of lab experiments has accelerated. Nonetheless, there remains considerable resistance among social scientists who argue that lab experiments lack "realism" and generalizability. In this article, we discuss the advantages and limitations of laboratory social science experiments by comparing them to research based on nonexperimental data and to field experiments. We argue that many recent objections against lab experiments are misguided and that even more lab experiments should be conducted.

Orley Ashenfelter, David Card, Using the Longitudinal Structure of Earnings to Estimate the Effect of Training Programs, The Review of Economics and Statistics, Vol. 67, No. 4 (Nov., 1985), pp. 648-660

Increasing wealth provides key motivation for students to forgo earnings and struggle through exams. But, as we argue in this paper, schooling generates many experiences and affects many dimensions of skill that, in turn, affect central aspects of individuals' lives. Schooling not only affects income, but also the degree to which one enjoys work, as well as one's likelihood of being unemployed. It leads individuals to make better decisions about health, marriage, and parenting. It also improves patience, making individuals more goal-oriented and less likely to engage in risky behavior. Schooling improves trust and social interaction, and may offer substantial consumption value to some students. We discuss various mechanisms to explain how these relationships may occur independent of wealth effects and present evidence that nonpecuniary returns to schooling are at least as large as pecuniary ones. Ironically, one explanation why some early school leavers miss out on these high returns is that they lack the very same decision-making skills that more schooling would help improve.

This paper examines the temperature-mortality relationship over the course of the twentieth-century United States both for its own interest and to identify potentially useful adaptations for coming decades. There are three primary findings. First, the mortality impact of days with mean temperature exceeding 807F declined by 75 percent. Almost the entire decline occurred after 1960. Second, the diffusion of residential air conditioning explains essentially the entire decline in hot day–related fatalities. Third, using Dubin and McFadden’s discrete continuous model, the present value of US consumer surplus from the introduction of residential air conditioning is estimated to be $85– $185 billion (2012 dollars).

A reduction in trade barriers generally will affect the environment by expanding the scale of economic activity, by altering the composition of economic activity, and by bringing about a change in the techniques of production. We present empirical evidence to assess the relative magnitudes of these three effects as they apply to further trade liberalization in Mexico.

We study subjects who were asked to fill letters into envelopes with a remuneration independent of output. In the "pair" treatment, two subjects worked at the same time in the same room, and peer effects were possible. In the "single" treatment, subjects worked alone, and peer effects were ruled out. We find evidence of peer effects in the pair treatment because the standard deviations of output are smaller within pairs than between pairs. Moreover, average output is higher in the pair treatment: thus, peer effects raise productivity. Finally, low-productivity workers are the most sensitive to the behavior of peers.

By 1989 the Michigan Panel Study on Income Dynamics (PSID) had experienced approximately 50 percent sample loss from cumulative attrition from its initial 1968 membership. We study the effect of this attrition on the unconditional distributions of several socioeconomic variables and on the estimates of several sets of regression coefficients. We provide a statistical framework for conducting tests for attrition bias that draws a sharp distinction between selection on unobservables and on observables and that shows that weighted least squares can generate consistent parameter estimates when selection is based on observables, even when they are endogenous. Our empirical analysis shows that attrition is highly selective and is concentrated among lower socioeconomic status individuals. We also show that attrition is concentrated among those with more unstable earnings, marriage, and migration histories. Nevertheless, we find that these variables explain very little of the attrition in the sample, and that the selection that occurs is moderated by regression-to-the-mean effects from selection on transitory components that fade over time. Consequently, despite the large amount of attrition, we find no strong evidence that attrition has seriously distorted the representativeness of the PSID through 1989, and considerable evidence that its cross-sectional representativeness has remained roughly intact.

Why the Apple Doesn't Fall Far: Understanding Intergenerational Transmission of Human Capital by Sandra E. Black, Paul J. Devereux and Kjell G. Salvanes. Published in volume 95, issue 1, pages 437-449 of American Economic Review, March 2005

This paper examines the history of internal migration in the United States since the 1980s. By most measures, internal migration in the United States is at a 30-year low. The widespread decline in migration rates across a large number of subpopulations suggests that broad-based economic forces are likely responsible for the decrease. An obvious question is the extent to which the recent housing market contraction and the recession may have caused this downward trend in migration: after all, relocation activity often involves both housing market activity and changes in employment. However, we find relatively small roles for both of these cyclical factors. While we will suggest a few other possible explanations for the recent decrease in migration, the puzzle remains. Finally, we compare U.S. migration to other developed countries. Despite the steady decline in U.S. migration, the commonly held belief that Americans are more mobile than their European counterparts still appears to hold true.