Moritz Marbach
moritz-marbach.com
Moritz Marbach
@moritz-marbach.com
I do research on the role of migration in politics. Associate Professor at UCL. Previously Texas A&M, Immigration Policy Lab and University of Mannheim. moritz-marbach.com
We demonstrate that there is a compositional effect: using survey data, we show that leavers were 18 pp less likely to support the incumbent than stayers. Thus, in constituencies with more out-migration, the incumbent vote share increased.
November 13, 2025 at 1:13 PM
Using constituency-level electoral data, we show that in East German constituencies with more out-migration between 1990–1994, the incumbent vote share increased. What explains this? Do voters reward the incumbent for high out-migration (sparked by increasing unemployment)? Unlikely.
November 13, 2025 at 1:13 PM
To illustrate the formal results, we study the case of East Germany after reunification, when more than 9% of East Germans moved to former West Germany. How did this exodus affect electoral support for the incumbent coalition government in the 1994 federal election across East Germany?
November 13, 2025 at 1:13 PM
These two types of effects are conceptually similar but different to natural (in)direct effects in mediation analysis. We discuss how to identify, estimate, and bound the compositional effect from in- and out-migration.
November 13, 2025 at 1:13 PM
When studying how internal migration affects changes in district-level electoral outcomes, it is important to separate the compositional effect (heterogeneity in political behavior between movers and stayers) from the exposure effect (change in political behavior due to exposure to migration).
November 13, 2025 at 1:13 PM
🚨New working paper: Compositional Effects, Internal Migration and Electoral Outcomes

osf.io/preprints/so...

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November 13, 2025 at 1:13 PM
5/ The limited number of classroom hours (320 vs. 600 hours), a non-standardized curriculum, and a lack of certification might explain the differences between the two programs.
January 13, 2025 at 10:00 PM
4/ But the pre-existing program did help refugees to secure jobs! Using a staggered difference-in-differences design, we find that participants were 4.4 percentage points more likely to be employed after just 1 year of starting the course, rising to 12 p.p. after 18 months.
January 13, 2025 at 10:00 PM
3/ Using a regression discontinuity design, we compare refugees who arrived in Germany before and after the eligibility cutoff for the ad hoc program, observing refugee employment outcomes over nearly 2 years. We find that the ad hoc program had no impact on employment.
January 13, 2025 at 10:00 PM
1/ Over 1 million refugees arrived in Germany in 2015. When established language training programs ("Integrationskurse") reached capacity, the Federal Employment Agency swiftly launched a new ad hoc program ("Einstiegskurse zur Deutschförderung") to enroll more.
January 13, 2025 at 10:00 PM
🚨New paper: Does ad hoc language training improve the economic integration of refugees? Evidence from Germany’s response to the Syrian refugee crisis 🚨

w/ Ehsan Vallizadeh, @niklas-harder.bsky.social, Dominik Hangartner, Jens Hainmueller

doi.org/10.1093/jrss...
January 13, 2025 at 10:00 PM
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October 29, 2024 at 3:06 PM
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August 30, 2024 at 1:11 PM
4/ Comparing refugees who were matched with similar refugees who registered but were not matched with a host due to host unavailability, we find that refugees who receive and accept the offer for accommodation are much better integrated.
April 23, 2024 at 6:13 PM
🚨New paper: The Impact of Private Hosting on the Integration of Ukrainian Refugees 🚨

w/ Mathis Herpell, Niklas Harder, Alexandra Orlova, Dominik Hangartner, Jens Hainmueller

osf.io/preprints/so...

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April 23, 2024 at 6:12 PM