Publications

Better Together? Heterogeneous Effects of Tracking on Student Achievement. (2021). The Economic Journal, Volume 131, Issue 635, pp. 1269–1307. [Ungated version here.] [Replication package here.]


Abstract: I study the effects of early between-school ability tracking on student achievement. For identification I exploit institutional differences between German federal states: in all states, about 40% of students transition to separate academic-track schools after comprehensive primary school. Depending on the state, the remaining student body is either directly tracked between two additional school types or taught comprehensively for another two years. Comparing these students before and after tracking in a triple-differences framework, I find evidence for positive effects of prolonged comprehensive schooling on mathematics and reading scores. These are almost entirely driven by large effects for low-achievers, whereas for high-achievers effects are null. Early and rigid forms of tracking can thus impair both equity and efficiency of school systems.
TLDR: I summarize my main findings in this Twitter thread.
For this paper I was awarded the NEPS Publication Award 2021.

No Evidence that Strict Educational Tracking Improves Student Performance through Classroom Homogeneity. A Critical Reanalysis of Esser and Seuring (2020). (2021). (joint with Jan Paul Heisig, WZB Berlin & FU Berlin). Zeitschrift für Soziologie, Volume 51, Issue 1, pp. 99–111. [Replication package here.]


Abstract: In a recent contribution to this journal, Esser and Seuring (2020) draw on data from the National Educational Panel Study to attack the widespread view that tracking in lower secondary education exacerbates inequalities in student outcomes without improving average student performance. Exploiting variation in the strictness of tracking across 13 of the 16 German federal states (e.g., whether teacher recommendations are binding), Esser and Seuring claim to demonstrate that stricter tracking after grade 4 results in better performance in grade 7 and that this can be attributed to the greater homogeneity of classrooms under strict tracking. We show these conclusions to be untenable: Esser and Seuring’s measures of classroom composition are highly dubious because the number of observed students is very small for many classrooms. Even when we adopt their classroom composition measures, simple corrections and extensions of their analysis reveal that there is no meaningful evidence for a positive relationship between classroom homogeneity and student achievement—the channel supposed to mediate the alleged positive effect of strict tracking. We go on to show that students from more strictly tracking states perform better already at the start of tracking (grade 5), which casts further doubt on the alleged positive effect of strict tracking on learning progress and leaves selection or anticipation effects as more plausible explanations. On a conceptual level, we emphasize that Esser and Seuring’s analysis is limited to states that implement different forms of early tracking and cannot inform us about the relative performance of comprehensive and tracked systems that is the focus of most prior research.

Working Papers

On Track to Success? Returns to Vocational Education against different Alternatives. (2022). (joint with Gugliemo Ventura, LSE, UCL & CVER). CVER Discussion Paper No. 38, London School of Economics and Political Science. Submitted.


Abstract: Many countries consider expanding vocational curricula in secondary education to boost skills and labour market outcomes among non-university-bound students. However, critics fear this could divert other students from more profitable academic education. We study labour market returns to vocational education in England, where until recently students chose between a vocational track, an academic track and quitting education at age 16. Identification is challenging because self-selection is strong and because students' next-best alternatives are unknown. Against this backdrop, we leverage multiple instrumental variables to estimate margin-specific treatment effects, i.e., causal returns to vocational education for students at the margin with academic education and, separately, for students at the margin with quitting education. Identification comes from variation in distance to the nearest vocational provider conditional on distance to the nearest academic provider (and vice-versa), while controlling for granular student, school and neighbourhood characteristics. The analysis is based on population-wide administrative education data linked to tax records. We find that the vast majority of marginal vocational students are indifferent between vocational and academic education. For them, vocational enrolment substantially decreases earnings at age 30. This earnings penalty grows with age and is due to wages, not employment. However, consistent with comparative advantage, the penalty is smaller for students with higher revealed preferences for the vocational track. For the few students at the margin with no further education, we find merely tentative evidence of increased employment and earnings from vocational enrolment.
TLDR: I summarize our main findings in this Twitter thread.
For this paper I was awarded the BeNA Innovative Research Award 2020 and it won the ifo Munich's Big Data research competition. 

De-Tracking at the Margin: How alternative Secondary Education Pathways affect Student Attainment. (2023). (joint with Camilla Borgna, University of Turin & Collegio Carlo Alberto). Revision requested.


Abstract: Since the 1960s, several countries have adopted major reforms towards comprehensive schooling, but even in countries that eschewed such structural de-tracking reforms, tracked school systems have become more flexible over time. The effects of such marginal processes of de-tracking are understudied compared to structural reforms. To fill this gap we estimate how the addition of non-selective `comprehensive schools' (integrierte Gesamtschule) and hybrid `vocational high schools' (berufliches Gymnasium/Fachgymnasium) to the traditional schools of Germany's three-tiered tracked school system have affected student attainment. Both offer an alternative pathway towards the university-entrance certificate (Abitur), which traditionally could only be obtained on academic-track schools (Gymnasium). However, their logic of de-tracking is quite different because comprehensive schools cover the entire secondary phase, hence offering an alternative to all of tracked schooling, while vocational high schools only cover the upper-secondary grades, hence only offering an upgrading option for non-academic-track students. Our empirical strategy exploits regional and temporal differences in the availability of these schools. We draw on yearly administrative records that cover the universe of German students, schools, and graduates to compile a county-level panel of local school supply and upper-secondary attainment for 13 cohorts between 1995 and 2007.  Cross-sectionally, we find that the supplies of all three school types that award the university-entrance certificate correlate positively with its attainment, but for comprehensive and academic-track schools this association is largely spurious, i.e., due to regional differences in educational demand. For vocational high schools, in contrast, we find robust evidence for a positive supply-side effect on attainment, confirmed in two-way fixed-effects, difference-in-differences, and event-study models. We argue that the reasons for their success lies in vocational high schools' hybrid nature and in that they complement the institutional logic of the tracking system, whereas comprehensive schools contradict it.

Work in Progress

Rank Effects in a Tracked School System. (joint with Michael Becker, TU Dortmund & DIPF, and Felix Weinhardt, EU Viadrina & DIW Berlin).

Heterogeneity in the Returns to Vocational Education by the Business Cycle and Automation Risk. (joint with Guglielmo Ventura, LSE, UCL & CVER).

The Effects of Separate Preparatory Language Classes on Socio-Emotional Outcomes of Refugee Children. (joint with Pia Schilling, U Konstanz).


Policy Publications

Längeres gemeinsames Lernen macht einen Unterschied. WZBrief Bildung 40. WZB Berlin Social Science Center.


For this policy brief I was awarded the Friends of the WZB Award 2020.
Für besseren Datenzugang im Bereich Bildung. Stellungnahme aus dem Verein für Socialpolitik. (2023). (joint with Hertweck, F., Isphording, I. E., Schneider, K. & Spieß, C. K.) RatSWD Working Paper 282/2023. Rat für Sozial- und Wirtschaftsdaten (RatSWD).
Abstract: Die Stellungnahme der Arbeitsgruppe „Bildungsdaten“ zeigt die gravierenden Datenmängel im Bereich der Verfügbarkeit und Verknüpfbarkeit von Bildungsdaten in Deutschland auf. Sie fordert die Umsetzung eines Bildungsverlaufsregisters über alle Stufen formaler Bildung sowie den regelhaften Zugang der Forschung zu diesen Daten. International würde Deutschland mit einem derartig verknüpfbaren Bildungsverlaufsregister an die Standards anderer europäischer Staaten aufschließen.
Bildungsdaten: Datenlücken durch ein Bildungsverlaufsregister schließen. (2023). (joint with Hertweck, F., Isphording, I. E., Schneider, K. & Spieß, C. K.) Wirtschaftsdienst, 103(11), 733-736.
Abstract: Evidence-based education policy needs comprehensive data. Education economists of the Verein für Socialpolitik call for the implementation of a longitudinal education register in Germany to understand the complex interrelationships of education systems. The education register should cover all levels of formal education and include data on student performance in order to close a serious data gap in Germany. The statement also calls for regular access to this data for independent research. Once implemented, the education register should enable linking with other data sources, for example from the labour market, tax and health records, in order to be able to analyse the long-term effects of education. By establishing a longitudinal education register, Germany would finally catch up with established standards of other European countries, creating a resource where education register data not only exists, but are available for researchers and can be linked with other data.