Publications
Abraham, D., Glejtková, K., & Krčál, O. (2025). The hidden costs of imposing minimum contributions to a global public good. Ecological Economics, 227, 108346. https://doi.org/10.1016/j.ecolecon.2024.108346
Abraham, D., Greiner, B., & Stephanides, M. (2023). On the Internet you can be anyone: An experiment on strategic avatar choice in online marketplaces. Journal of Economic Behavior & Organization, 206, 251-261. https://doi.org/10.1016/j.jebo.2022.11.033
Abraham, D., Corazzini, L., Fišar, M., & Reggiani, T. (2023). Coordinating donations via an intermediary: The destructive effect of a sunk overhead cost. Journal of Economic Behavior & Organization, 211, 287-304. https://doi.org/10.1016/j.jebo.2023.05.006
Working Papers
"Managing Excess Demand for Primary Care: Evidence from Online Experiments" (with Ondřej Krčál and Jonathan Stäbler) link.
Primary healthcare systems in many developed countries are under strain, partly due to unrestricted patient demand. In response, policymakers have introduced measures to curb unnecessary GP visits, including (i) instituting a small upfront fee for GP visits, (ii) implementing a self-report based triage system, and (iii) providing more information to patients about their condition before they make an appointment with their GP. We evaluate the effectiveness of these approaches using two online experiments with a representative sample of UK adults. The first experiment involves induced monetary incentives in a laboratory-style study while the second is a health-framed vignette study. We find that while all three interventions are effective in the laboratory study, only the intervention that provides patients with more information about their condition reduces low-priority demand in the vignette study. We discuss implications for policy and for the study of health-related decision-making.
"(De)otivational Effects of Feeling (Dis)trusted" (with Ondřej Krčál) link. Under Review.
We investigate how workers’ motivation is influenced by whether they feel trusted or not by managers. In a laboratory experiment, responsibility for a manager’s earnings is divided unequally between two workers. We vary whether this decision is made by the manager or a random device on the manager’s behalf. Importantly, having more/less responsibility does not affect the workers’ wages. Despite this, we find that workers provide less effort when they are deliberately, vs. randomly, assigned lower responsibility. We find a smaller, less robust positive effect of learning one is more trusted. We examine two inter-related mechanisms and show that both beliefs about expected effort as well as emotions triggered when learning about the manager’s decision help explain our results.
"Dictator giving when recipients can opt out" (with Ondřej Krčál) link
Participants' willingness to give in the dictator game has been found to be very sensitive to extending their choice set so that they can also take from recipients. To reduce this choice-set effect, we make the game less abstract by permitting potential recipients to opt out of it. Across four treatments, we vary whether taking is permitted and whether recipients can opt out of the game. Results suggest that while the choice-set effect is replicated when recipients cannot opt out, it plays less of a role when recipients enter the game voluntarily. We rule out a competing reciprocity-based explanation for this result, and conclude that the modified opt-in dictator game may provide a less sensitive measure of other-regarding preferences.
"Does Discrimination Beget Discrimination? The Effect of Exclusion on Ingroup Bias" (with Astrid Hopfensitz) link
We examine whether being included in or excluded from a group based on a given dimension of one's identity increases the salience of this identity dimension in two unrelated interactions. Using a laboratory experiment, we induce two ex-ante equally relevant dimensions of identity and have one member of a three-member team excluded, ostensibly because they do not share a given dimension of their identity with the other two (included) members of the team. We subsequently measure ingroup bias of all participants on both identity dimensions using a disinterested dictator game. We find that while there is no effect of exclusion, being included increases ingroup bias on the identity dimension that was the basis for inclusion. Included individuals are also more likely to want to interact with those who share their identity on the included dimension relative to participants in a separate baseline condition. These results suggest that being included calls more attention to the aspect of one's identity that was the basis for inclusion resulting in stronger ingroup bias on this dimension.
Selected Work-in-Progress
"Upstream Corrections and Team Performance" (with Maria Polipciuc and Oliver Kirchkamp)
Other
Fišar, M., Greiner, B., Huber, C., Katok, E., Ozkes, A. I., & Management Science Reproducibility Collaboration. (2024). Reproducibility in Management Science. Management Science, 70(3), 1343-1356. https://doi.org/10.1287/mnsc.2023.03556
Note: Member of the Management Science Reproducibility Collaboration