Welcome to my website!
I am a Senior Researcher at BiB Berlin, a Research Fellow at WZB Berlin, a Member of the Berlin School of Economics and CRC TRR 190 "Rationality and Competition", a Research Affiliate at IZA, and a Member of the Evaluation Consortium of the Startchancen Program
My research interests lie in the area of applied microeconomics, with a focus on education and political economy. I use causal identification strategies as well as field and survey experiments to study topics including the effects of AI environments, mental health, information, and educational programs and reforms on decision-making behavior, academic performance, political preferences and inequality.
Contact
BiB Federal Institute for Population Research (Berlin Office)
Friedrichstrasse 50, 10117 Berlin, Germany
WZB Berlin Social Science Center
Reichpietschufer 50, 10785 Berlin, Germany
Email: firstname.lastname@wzb.eu
Working Papers
AI Tutoring Enhances Student Learning Without Crowding Out Reading Effort, with Holger Rau and Rainer M. Rilke (2025)
We study how AI tutoring affects learning in higher education through a randomized experiment with 334 university students preparing for an incentivized exam. Students either received only textbook material, restricted access to an AI tutor requiring initial independent reading, or unrestricted access throughout the study period. AI tutor access raises test performance by 0.23 standard deviations relative to control. Surprisingly, unrestricted access significantly outperforms restricted access by 0.21 standard deviations, contradicting concerns about premature AI reliance. Behavioral analysis reveals that unrestricted access fosters gradual integration of AI support, while restricted access induces intensive bursts of prompting that disrupt learning flow. Benefits are heterogeneous: AI tutors prove most effective for students with lower baseline knowledge and stronger self-regulation skills, suggesting that seamless AI integration enhances learning when students can strategically combine independent study with targeted support.
Behavioral policy, such as leveraging defaults, is increasingly employed by governments worldwide, but has sometimes faced public backlash, which limits political feasibility. We conducted a survey experiment with a large, representative sample to explore how the narrative describing the psychological mechanism by which a default rule impacts a socially significant outcome affects public approval. Respondents are presented with a vignette in which an unemployed person follows a default to participate in further training. We experimentally vary the narrative about his reasons for doing so. Compared to the baseline condition in which no information on the psychological mechanism is provided, voluntary ignorance, involuntary ignorance, perceived social expectations and perceived social pressure each reduce policy approval. These factors also lead to more negative perceptions of the default rule's impact on the decision maker’s welfare and autonomy. The benign mechanism of deliberate endorsement, however, does not significantly raise approval or perceptions. We show that these findings hold irrespective of assumed preferences and discuss their practical implications.
Mindfulness-based meditation practices are becoming increasingly popular in Western societies, including in the business world and in education. While the scientific literature has largely documented the benefits of mindfulness meditation for mental health, little is still known about potential spillovers of these practices on other important life outcomes, such as performance. We address this question through a field experiment in an educational setting. We study the causal impact of mindfulness meditation on academic performance through a randomized evaluation of a well-known 8-week mindfulness meditation training delivered to university students on campus. As expected, the intervention improves students' mental health and non-cognitive skills. However, it takes time before students' performance can benefit from mindfulness meditation: we find that, if anything, the intervention marginally decreases average grades in the short run, i.e., during the exam period right after the end of the intervention, whereas it significantly increases academic performance, by about 0.4 standard deviations, in the long run (ca. 6 months after the end of intervention). We investigate the underlying mechanisms and discuss the implications of our results.
This paper studies responses to high-stakes incentives arising from early ability tracking. We use three complementary research designs exploiting differences in school track admission rules at the end of primary school in Germany's early ability tracking system. Our results show that the need to perform well to qualify for a better track raises students' math, reading, listening, and orthography skills in grade 4, the final grade before students are sorted into tracks. Evidence from self-reported behavior suggests that these effects are driven by greater study effort but not parental responses. However, we also observe that stronger incentives decrease student well-being and intrinsic motivation to study.
Publications
Randomized experiments are often viewed as the “gold standard” of scientific evidence, but people's skepticism towards experiments has compromised their viability in the past. We study preferences for experimental policy evaluations in a representative survey in Germany (N > 1,900). We find that a majority of 75 % supports the idea of small-scale evaluations of policies before enacting them at a large scale. Experimentally varying whether the evaluations are explicitly described as “experiments” has a precisely estimated overall zero effect on public support. Our results indicate political leeway for experimental policy evaluation, a practice that is still uncommon in Germany.
We investigate the effect of team formation and task characteristics on performance in high-stakes team tasks. In two field experiments, randomly assigned teams performed significantly better than self-selected teams in a task that allowed for an unequal work distribution. The effect was reversed if the task required the two team members to contribute more equally. Investigating mechanisms, we observe that teams become more similar in ability and report to cooperate better when team members can choose each other. We show how different levels of skill complementarity across tasks may explain our results: If team performance largely depends on the abilities of one team member, random team assignment may be preferred because it leads to a more equal distribution of skills across teams. However, if both team members’ abilities play a significant role in team production, the advantage of random assignment is reduced, and the value of team cooperation increases.
"Confidence in Knowledge or Confidence in the Ability to Learn: An Experiment on the Causal Effects of Beliefs on Motivation" (with D. Sliwka), Games and Economic Behavior, 111, 2018: 122-142 (non-paywalled version here)
"Support for Free-market Policies and Reforms: Does the Field of Study Influence Students’ Political Attitudes?” (with B. Kauder, N. Potrafke, and H.W. Ursprung), European Journal of Political Economy, 48, 2017: 180-197 (non-paywalled version here)
“Effects of German Universities’ Excellence Initiative on Ability Sorting of Students and perceptions of Educational Quality” (with P. Kampkötter), Journal of Institutional and Theoretical Economics, 173(4), 2017: 662-687 (non-paywalled version here)
We investigate potential spillover effects from the German Excellence Initiative on university education. Using data from a representative student survey, we find that winning the competition allows universities to enroll significantly better high-school graduates in three subsequent admission terms. We then investigate a possible channel explaining the effect on admissions by studying whether the excellence label improves students' perception of educational quality. We find that the label significantly improves students' ratings of a university's educational quality and their job market expectations immediately following the award. However, ratings largely return to previous levels when students are surveyed three years later, although the status persists.
“Ist sanfter Paternalismus ethisch vertretbar? Eine differenzierende Betrachtung aus Sicht der Freiheit” (with S. Lotz), Sozialer Fortschritt/German Review of Social Policy, 63(3), 2014: 52-58
-- English version -- : Is Soft Paternalism Ethically Legitimate? - The Relevance of Psychological Processes for the Assessment of Nudge-Based Policies, Cologne Graduate School Working Paper, 5(2), 2014
In this article we develop a taxonomy of behavioral policy measures proposed by Thaler and Sunstein (2008). Based on this taxonomy, we discuss the ethical legitimacy of these measures. First, we explain two common reservations against nudges (choice architecture) rooted in utilitarian and Kantian ethics. In addition to wellbeing, we identify freedom of action and freedom of will (autonomy) as relevant ethical criteria. Then, using practical examples, we develop a taxonomy that classifies nudges according to the psychological mechanisms they use and separately discuss the legitimacy of several types of behavioral policy measures. We hope to thereby make a valuable contribution to the debate on the ethical legitimacy of behavioral policy making.
Selected Work in Progress
Explaining preferences for smartphone bans in schools (representative survey experiment), with Mathias Huebener, Sophia Schmitz, and Katharina Spiess
AI tutoring, student behavior, and academic performance (field experiment) with Holger Rau and Rainer M. Rilke
Effects of stress on political outgroup bias (field experiment), with Maja Adena and Lea Cassar
Evaluation of the Startchancen program (2025 - 2035), member of research consortium
Some of my Presentations to Watch and Listen to Online
Introduction to Ernst Fehr's WZB Distinguished Lecture in Social Sciences, October 2020
Policy Contributions
Fischer, M., Voigt, M. (2025) Black Box Bildung: Die Potenziale von Schuldaten für ein lernendes Schulsystem, Kurzstudie im Auftrag der Open Knowledge Foundation
Bach, M., Fischer, M. (2021) Mit verbindlichen Grundschulempfehlungen erreichen Grundschüler/innen bessere Leistungen, empfinden aber auch mehr Stress, ZEW Policy Brief Nr. 21-01
Fischer, M. (2020) Delayed policy responses to COVID-19: The role of the WHO’s structural problem, Coronavirus and its Societal Impact - Highlights from WZB Research, WZB Berlin Social Science Center