Research Interests

Electoral Systems

I am particularly interested in the question of which preferences voters have in electoral system design. Moreover, I focus on the case of open-list PR systems and analyze how voters select candidates.

Party Competition

I study which positions parties take and which issues they emphasize. I put special emphasis on party competition in multi-level settings. As on of the leaders of the Local Manifesto Project I published several articles on party position taking at the local level.

Research Methods

I specialize in using quantitative research methods with an emphasis on causal identification strategies as well as text-as-data approaches. This includes approaches such as: conjoint experiments, regression discontinuity designs, topic models and text scaling.


New Publication in Electoral Studies on the Incumbency Advantage in PR Systems at the Local and National Level

Do candidates in local elections in a system using proportional representation benefit from an incumbency advantage? And which factors moderate the strength of this incumbency bonus? Analyzing seven decades of Irish local elections (1942--2019) conducted under proportional representation through the single transferable vote, we reassess and extend the mixed evidence on the incumbency advantage under proportional representation and in lower-order elections. By applying the Regression Discontinuity Design, we find that the incumbency advantage is at least as strong in Irish local as in general elections, which are conducted under the identical electoral system. In addition, we show that marginally elected candidates in local elections have much higher reelection probabilities when they do not face a high-quality candidate in their local electoral area after getting elected. The results point the importance of name recognition as a major driver of the incumbency advantage.

New Publication in Acta Politica on Ballot Position Effects and Postal Voting [open access]

Various studies demonstrate that candidates at the top of the party list have a strong advantage in preferential voting systems, particularly under open-list PR. Such ballot position effects can be explained by voters’ tendency to rely on easily available information shortcuts when selecting a candidate. In this paper, we argue that the strength of ballot position effects depends on the context of how voters cast their vote. Specifically, we argue that postal voters are less likely to rely on the ballot position cue compared to voters who vote on election day for two reasons. First, postal voters might be more politically interested. Second, postal voters have more time to assess additional information about the candidates. The hypothesis is tested by analyzing newly collected data from two open-list PR elections in the German federal state of Hamburg. The results confirm the theoretical expectations: Ballot position effects are substantively weaker among postal voters. Additional analyses suggest that differences in the political interest between postal voters and election day voters are unlikely to fully explain these results. These findings advance our understanding of ballot position effects and voters’ use of information shortcuts more generally.