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Unsägliche Industriepolitik und ein übergriffiger StaatReint GroppThe Pioneer, 1. März 2025
We study the importance of teacher subject knowledge for student performance in Sub-Saharan Africa using unique international assessment data for sixth-grade students and their teachers. To circumvent bias due to unobserved student heterogeneity, we exploit variation within students across math and reading. Teacher subject knowledge has a modest impact on student performance. Exploiting vast cross-country differences in economic development, we find that teacher knowledge is effective only in more developed African countries. Results are robust to adding teacher fixed effects and accounting for potential sorting based on subject-specific factors.
Ample evidence indicates that a person’s human capital is important for success on the labor market in terms of both wages and employment prospects. However, unlike the efforts to identify the impact of school attainment on labor-market outcomes, the literature on returns to cognitive skills has not yet provided convincing evidence that the estimated returns can be causally interpreted. Using the PIAAC Survey of Adult Skills, this paper explores several approaches that aim to address potential threats to causal identification of returns to skills, in terms of both higher wages and better employment chances. We address measurement error by exploiting the fact that PIAAC measures skills in several domains. Furthermore, we estimate instrumental-variable models that use skill variation stemming from school attainment and parental education to circumvent reverse causation. Results show a strikingly similar pattern across the diverse set of countries in our sample. In fact, the instrumental-variable estimates are consistently larger than those found in standard least-squares estimations. The same is true in two “natural experiments,” one of which exploits variation in skills from changes in compulsory-schooling laws across U.S. states. The other one identifies technologically induced variation in broadband Internet availability that gives rise to variation in ICT skills across German municipalities. Together, the results suggest that least-squares estimates may provide a lower bound of the true returns to skills in the labor market.
International data from the PIAAC survey allow estimation of comparable labor-market returns to skills for 32 countries. Returns to skills are larger in faster growing economies, consistent with the hypothesis that skills are particularly important for adaptation to economic change.
In a laboratory experiment, we investigate the interaction of two prominent firm strategies to increase worker effort: team building and control. We compare a team-building treatment where subjects initially play a coordination game to gain common experience (CE) with an autarky treatment where subjects individually perform a task (NCE). In both treatments, subjects then play two-player control games where agents provide costly effort and principals can control to secure a minimum effort. CE agents always outperform NCE agents. Conditional on control, however, CE agents’ effort is crowded out more strongly, with the effect being most pronounced for agents who successfully coordinated in the team-building exercise. Differential reactions to control perceived as excessive is one explanation for our findings.
Existing estimates of the labor-market returns to human capital give a distorted picture of the role of skills across different economies. International comparisons of earnings analyses rely almost exclusively on school attainment measures of human capital, and evidence incorporating direct measures of cognitive skills is mostly restricted to early-career workers in the United States. Analysis of the new PIAAC survey of adult skills over the full lifecycle in 23 countries shows that the focus on early-career earnings leads to underestimating the lifetime returns to skills by about one quarter. On average, a one-standard-deviation increase in numeracy skills is associated with an 18 percent wage increase among prime-age workers. But this masks considerable heterogeneity across countries. Eight countries, including all Nordic countries, have returns between 12 and 15 percent, while six are above 21 percent with the largest return being 28 percent in the United States. Estimates are remarkably robust to different earnings and skill measures, additional controls, and various subgroups. Instrumental-variable models that use skill variation stemming from school attainment, parental education, or compulsory-schooling laws provide even higher estimates. Intriguingly, returns to skills are systematically lower in countries with higher union density, stricter employment protection, and larger public-sector shares.
Measuring skill mismatch is problematic, because objective data on an individual skill level are often not available. Recently published data from the Program for the International Assessment of Adult Competencies (PIAAC) provide a unique opportunity for gauging the importance of skill mismatch in modern labor markets. This paper systematically compares existing measures of skill mismatch in terms of their implications for labor market outcomes. We also provide a new measure that addresses an important limitation of existing measures, namely, assigning a single competency score to individuals. We find that the importance of skill mismatch for individual earnings differs greatly, depending on the measure of mismatch used.
We show in a laboratory experiment that the same method of group induction carries different behavioral consequences. These heterogeneous treatment effects can be directly related to the quality of the relationship established between the subjects. Our results indicate the importance of manipulation checks in group-formation tasks in economic experiments.
