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This paper assesses the performance of classical strategies to control for (pre-)trends in difference-in-differences designs.

This paper assesses the performance of classical strategies to control for (pre-)trends in difference-in-differences designs.

We focus on three main approaches: controlling for or matching on pre-trends, extrapolating linear trends, and controlling for group-by-time fixed effects. Through Monte Carlo simulations using real labor market data, we examine incidental trends that may emerge due to correlations between treatment and unobserved characteristics.

Drawing on these simulations and supporting analytical results, we provide intuitive insights into the performance of these methods and further formalize the conditions that justify their application.

This study analyses the relationship between informal on-the-job training and turnover of new hires.

We analyze the relationship between informal on-the-job training and turnover of new hires. To this end, we use unique survey data about different aspects of informal co-worker training and link it to both firm-level and individual-level administrative data.

We find that informal training is negatively associated with turnover of new hires six months after entering the firm. However, this relationship becomes smaller and statistically weaker after 12 months.

Further heterogeneity analysis reveals a trade-off after one year, as onboarding can, to some extent, contribute to increased retention in firms with a lower wage premium and thereby help to mitigate costly worker turnover in these firms.

Joint work with Didier Fouarge and Carolin Linckh.

This study investigates how mentoring programs can be successfully scaled to transform the education system in Germany.

The shortage of skilled workers is a central challenge for the German labor market – 18% of young adults (20-34 years) do not have any occupational degree, and this proportion is up to twice as high for those from disadvantaged backgrounds.

One promising approach to tackle this challenge is through individual mentoring programs. The project team investigates how mentoring programs can be successfully scaled to transform the education system in Germany and promote social equality. Whether, and to what extent, such programs have a positive impact is crucial to the successful design of societal transformation processes. The research team is cooperating with a leading mentoring provider and conducting a randomized controlled trial with 3,000 disadvantaged young people to analyze the causal effects of mentoring. We plan to examine four key areas of scale-up: recruitment of mentors, general equilibrium effects, replacement of high-cost matching methods with machine learning, and the horizontal expansion of mentoring to vocational schools and apprentices.

The results will provide both scientific and practical insights into optimal technologies for rolling out interventions that serve societal transformation and the promotion of equal opportunities.

This paper studies the real effects of monetary policy on firms' labor adjustment.

This paper studies the real effects of monetary policy on firms' labor adjustment. Using detailed bank data together with administrative firm and worker data for Germany, we find that firms reduce employment in response to contractionary monetary policy.

We show that this employment reduction results from a relative decline in inflows rather than outflows. Inflows fall in particular for low-wage workers, whereas firms retain high-wage workers. Outflows for transitions to unemployment increase, while employment-to-employment outflows falls.

We interpret this as evidence for labor hoarding. Using variation in the bank exposure to monetary policy, we show that these results are driven by the exposure of the firm to the bank-lending channel.

This study examines the relationship between local income inequality and the centre bias.

We examine the relationship between local income inequality / local income levels on the one hand, and the “centre bias” on the other. The latter refers to people’s misconception of being in the middle of the national income distribution, rather than at its more extreme ends.

Local income distributions shape perceptions of inequality because co-residents are a reference group that affects the availability of opportunities for upward and downward social comparison. Theoretically, we outline four mechanisms that could link higher and lower local income inequality and income levels to residents' perceptions of their own relative income position (exposure vs. segregation, contrast vs. assimilation). Empirically, we link geo-referenced survey data to external datasets containing information on income inequality and income levels in respondents' home municipalities. Results suggest that higher local inequality is associated with a lower “centre bias” for both poor and rich respondents, supporting an “exposure” mechanism.

With respect to poorer versus richer municipalities, we find that only by tendency, either group estimates their position in the national income distribution to be somewhat higher. However, this evidence in favor of the “assimilation” mechanism is weak.

This study is about prevalence, perceived costs and consequences of sexual harassment (SH) in German workplaces.

We study the prevalence, perceived costs and consequences of sexual harassment (SH) in German workplaces. We first use a discrete choice experiment to estimate workers' willingness to pay (WTP) for workplaces without a history of known SH cases and preventive firm measures. Women, particularly early in their careers, display the highest WTP. Preventive measures significantly increase the attractiveness of workplaces, even when there is a history of SH.

Motivated by these results, we then document SH experiences using new data from the Linked Personnel Panel (LPP) and the IAB-OPAL online panel. SH is widespread: 20 percent of employees have either experienced SH at work personally or in their close work environment. Women are affected significantly more often than men. Women are also less likely to trust that leadership will respond appropriately to reported cases, and this lack of trust correlates with higher experienced incidence rates. Firms with active complaint procedures and preventive measures report greater employee awareness and more open discussion of SH. Taken together, our findings provide a strong economic rationale for preventive policies.

This study shows how costly is inflation to workers.

How costly is inflation to workers? Answers to this question have focused on the path of real wages during inflationary periods. We argue that workers must take costly actions (“conflict”) to have nominal wages catch up with inflation, meaning there are welfare costs even if real wages do not fall as inflation rises. We study a menu-cost style model, where workers choose whether to engage in conflict with employers to secure a wage increase. We show that, following a rise in inflation, wage catch-up resulting from more frequent conflict does not raise welfare. Instead, the impact of inflation on worker welfare is determined by what we call “wage erosion”—how inflation would lower real wages if workers’ conflict decisions did not respond to inflation.

As a result, using observed wage growth to measure worker welfare understates the costs of inflation. We conduct a survey showing that workers are willing to sacrifice 1.75% of their wages to avoid conflict. Calibrating the model to survey data, incorporating conflict significantly raises the costs of inflation for workers.

Find here draft of the working paper.

This study evaluates the Education Maintenance Allowance in England.

We evaluate the Education Maintenance Allowance, a large conditional cash transfer that paid teenagers from lower-income backgrounds up to $3,200 per year to remain in full-time education beyond the compulsory school-leaving age.

Exploiting the program's staggered rollout in England, we find that it increased education participation and reduced crime. However, we find no improvements in test scores, no effect on qualifications beyond the lowest level, and a small negative effect on labour market outcomes up to age 30. A key channel appears to be delayed labour market entry without offsetting gains in human capital.

This study shows us that the city-size wage premium is larger for low-skilled than for high-skilled workers in Peru.

We use individual geocoded data from Peru and document that the city-size wage premium is larger for low-skilled than for high-skilled workers, in contrast with most developed countries. We interpret this evidence using a model of location choice with private amenity goods and non-homothetic preferences.

Skilled workers enjoy higher incomes and devote a higher expenditure share to amenity goods, such as private schools or upper-class neighborhoods. The supply of these amenities is subject to a fixed cost, and only sufficiently large cities have enough demand to offer them. Thus, skilled workers demand a higher wage premium to live in small cities, and the returns to working in a large city are smaller for them than for their unskilled counterparts. Our quantitative exercises indicate that the mechanism accounts for two-thirds of the gap in the city-size wage premium between high-skilled and low-skilled workers.

joint with Andrii Parkhomenko and Daniel Velásquez-Cabrera