Behavioral Anti-Bias Interventions in Context
My professorship is funded by a Lichtenberg Fellowship of the Volkswagen Foundation. The core question of my research program is: how can we design effective psychological (or behavioral) anti-bias interventions in contexts of systemic group-based injustice? I answer these questions by making three types of contributions to the literature on intergroup relations:
Primary Contribution
My research primarily focuses on anti-bias interventions that are structural rather than "light-touch" (i.e., inexpensive, brief, and easy to implement—see Annual Review of Psychology). Specifically, I study two key types of interventions: intergroup contact and behavioral memory interventions.
Intergroup Contact: I explore how sustained, programmatic, or institutionalized intergroup contact can reshape the social structures of participants' lives, distinguishing it from more transient forms of contact (e.g., laboratory or online interactions). My focus is on randomized studies testing the effects of structural intergroup contact interventions in contexts marked by high levels of intergroup conflict.
Remembrance Interventions: These interventions engage citizens in constructing collective memory, often embedding structural components. For example, the Stolpersteine counter-memorial (commemorative "stumbling stones") alters the physical architecture of local neighborhoods (see The Proceedings of the National Academy of Sciences). I investigate how participating in or contributing to such projects shapes individuals' engagement with past and present intergroup injustices.
Meta-Level Inquiry
At a broader level, my research examines systemic barriers that can undermine the impact of psychological intergroup interventions in contexts of entrenched group-based injustice. Examples of such barriers include non-supportive authorities or ongoing intergroup violence. I aim to identify strategies to proactively address and overcome these obstacles to maximize the effectiveness of interventions.
Methodological Contributions
Because assessing structural interventions outside laboratory settings is relatively novel in psychology, I frequently employ underutilized methods, such as field experiments, and critically examine their potential and limitations for advancing our understanding of human psychology.
Creating Ambassadors of Peace in Ethiopia
With: Tenaw G. Abate (Aarhus University), Dereje Abegaz (Policy Studies Institute Ethiopia), Lingerh Akalu (University of Gondar), Yohanes Ayele (Overseas Development Institute), Habtamu Edjigu (Policy Studies Institute Ethiopia), Cecilia Hyunjung Mo (University of California Berkley) and Solomon Z. Walelign (University of Gondar)
Intergroup contact is the most studied social psychological intervention for improving intergroup relations. However, its effectiveness in reducing prejudice amid ongoing ethnic violence in the Global South remains underexplored. This research investigates the impact of intergroup contact in Ethiopia, a nation grappling with deep ethnic tensions exacerbated by conflicts in regions such as Tigray, Amhara, and Oromia. These conflicts have fostered fear and resentment among ethnic groups.
The University of Gondar's Host Family Program aims to address these divides by pairing non-Amharan students with local Amharan families to encourage cross-ethnic dialogue. In this study, 720 students are randomly assigned to either 360 host families or a control group that does not participate in the program. At the academic year's end, questionnaires and behavioral games will measure whether sustained, meaningful contact reduces ethnic prejudice and increases trust and cooperation.
This field experiment offers a rare opportunity to examine intergroup contact in a setting marked by active ethnic conflict. It is funded by a grant from IDF to the University of Gondar and conducted by a large team of local and international researchers. You can read more about the project here: https://www.hertie-school.org/en/news/detail/content/ruth-ditlmann-joins-research-team-for-ethiopias-host-family-programme-to-combat-ethnic-prejudice
Combating Housing Discrimination against Roma people in Hungary
With: Luca Varadi (Central European University) and Ilka Gleibs (London School of Economics)
This project seeks to improve our understanding of how to combat housing discrimination against a highly marginalised group, Roma people, in a context where democracy is under threat: Hungary. A survey experiment with landlords and a field experiment on Budapest’s largest online housing platform, will be carried out to test the effectiveness of different strategies for reducing discriminatory behaviour. The project is expected to identify the most effective strategy, and then implement it at scale in collaboration with the municipality of Budapest. The project is funded by CIVICA.