It is widely believed that female students perform better when taught by female professors. However, little is known about the mechanisms explaining these gender match effects. Using administrative records from a German public university, which cover all programs and courses between 2006 and 2018, we show that gender match effects are sizable in smaller classes, but are absent in larger classes. These results suggest that direct and frequent interactions between students and professors are crucial for gender match effects to emerge. In contrast, the mere fact that one’s professor is female is not sufficient to increase performance of female students.

We revisit the employer size wage effect (ESWE) – arguably the most basic and influential departure from the law of one price for labor. Our main result is that this canonical fact disappears completely across establishments within the same firm, even though they operate in different local labor markets. We uncover and dissect this fact by including a firm fixed effect in otherwise standard cross-sectional regressions of wages on establishment size. We implement this demanding specification in population-wide triple-linked firm-establishment-employee data in Germany. This result is new in the ESWE literature (for which our paper also provides the first systematic meta-analysis). This wage-size decoupling is hard to square with the view that employment is determined along a finitely elastic employerspecific labor supply curve – i.e., employers pay exactly the minimum needed for the quantity of labor, but no more – the foundation of the monopsony view. By contrast, large multi-establishment firms (MEF) appear to hire off their labor supply curves (or those curves are very elastic), pay wage premia above the monopsonistic minimum, and leave excess labor supply. We find some evidence for a reemergence of the ESWE within low-premium MEFs. Overall, at least for the 25% of German employment in large firms for which the ESWE disappears, wage setting and employment determination may be better accounted for by alternative models, namely accommodating above-market-clearing wage premia and rationing of labor supply, such as efficiency wage theories.

I estimate management opposition to unions in terms of hiring discrimination in the German labor market. By sending 13,000 fictitious job applications, revealing union membership in the CV and pro-union sentiment via social media accounts, I provide evidence for hiring discrimination against union supporters. Callback rates are on average 15% lower for union members. Discrimination is strongest in the presence of a high sectoral share of union members and large firm size. I further explore variation in regional and sectoral strike intensity over time and find suggestive evidence that discrimination increases if a sector is exposed to an intense strike. Discrimination is positively associated with the sectoral share of firms that voluntarily orientate wages to collective agreements. These results indicate that hiring discrimination can be explained by union threat effects.