Stefan Müller

Stefan Müller

Assistant Professor

University College Dublin

About Me

I am an Assistant Professor (Lecturer) and Ad Astra Fellow in the School of Politics and International Relations at University College Dublin. Previously, I was a Senior Researcher in the Department of Political Science at the University of Zurich. I hold a PhD in Political Science from Trinity College Dublin.

My research focuses on political representation, party competition, political communication, and public opinion. I apply a range of research methods, such as quantitative text analysis, machine learning, speech recognition, computer vision, and quasi-experimental designs. My work has been published or is forthcoming in journals such as The Journal of Politics, Political Communication, Political Science Research and Methods, and Legislative Studies Quarterly, among others.

I am a founding member of the Connected_Politics Lab at University College Dublin and a non-resident fellow at the Digital Democracy Lab (University of Zurich). I am also a co-author of the quanteda R package for quantitative text analysis, member of the Quanteda Initiative, and maintainer of the Irish Polling Indicator.

Curriculum Vitae


Google Scholar Page

Peer-Reviewed Publications

Stefan Müller. Accepted for Publication. “The Temporal Focus of Campaign Communication.” The Journal of Politics.

Experiences from the past and present influence decision-making. Voting behavior at elections also involves retrospective and prospective considerations. Yet, we do not know the degree to which parties react to these considerations by emphasizing the past, present, and future. I posit that parties do not only make promises but face incentives to discuss the past and present. I also expect that incumbency status conditions emotive rhetoric across these temporal dimensions. Using supervised machine learning, I uncover the temporal rhetorical focus in 621 party manifestos published in nine countries between 1949 and 2017. Parties devote, on average, half of a manifesto to future promises, while the other half describes the past and present. Besides, I show that statements on the past and present drive previously observed differences in sentiment between incumbents and opposition parties. The findings underscore how the temporal dimension of campaign communication enhances our understanding of party competition.

Stefan Müller. Forthcoming. “Media Coverage of Campaign Promises Throughout the Electoral Cycle.” Political Communication (online first)

Previous studies conclude that governments fulfill a large share of their campaign pledges. However, only a minority of voters believe that politicians try to keep their promises, and many voters struggle to recall the fulfillment or breaking of salient campaign pledges accurately. I argue that this disparity between the public perception and empirical evidence is influenced by the information voters receive throughout the electoral cycle. I expect that the media extensively inform readers about political promises. In addition, I posit that news outlets focus more on broken than on fulfilled promises and that the focus on broken promises has increased over time. I find strong support for these expectations based on a new text corpus of over 430,000 statements on political commitments published between 1979 and 2017 in 22 newspapers during 33 electoral cycles in Australia, Canada, Ireland, and the United Kingdom. Newspapers inform voters regularly about announced, broken, and fulfilled promises. Yet, across the four countries, newspapers report at least twice as much on broken than on fulfilled promises. Moreover, this negativity bias in reports on political promises has increased substantively. The results have implications for studying campaign promises, negative information in mass media, and the linkages between voters and parties.

Stefan Müller and Tom Louwerse. 2020. “The Electoral Cycle Effect in Parliamentary Democracies.” Political Science Research and Methods 8(4): 795–802.

Does government party support decline in a monotonic fashion throughout the legislative cycle or do we observe a u-shaped 'electoral cycle effect'? Moving beyond the study of midterm election results, this is the first study to assess the cyclical pulse of government party support in parliamentary democracies based on over 25,000 voting intention polls from 171 cycles in 22 countries. On average, government parties lose support during the first half of the electoral cycle, but at most partially recover from their initial losses. Under single-party government and when prime ministers control cabinet dissolution, support tends to follow the previously assumed u-shaped pattern more strongly. Finally, we find that government parties hardly recover from early losses since the 2000s.

Shaun Bowler, Gail McElroy, and Stefan Müller. 2020. “Campaigns and the Selection of Policy-Seeking Representatives.” Legislative Studies Quarterly 45(3): 397–431.

Can voters learn meaningful information about candidates from their electoral campaigns? As with job market hiring, voters, like employers, cannot know the productivity of candidates, especially challengers, when they elect them. The real productivity of representatives only reveals itself after the election. We explore if the information revealed during the "hiring process" is a good signal of the legislative effort of elected representatives. In the incomplete information environment of election campaigns, candidates should turn to credible signals to indicate their "type" to voters. Campaigns – and campaigning – are means by which candidates can, in principle, signal their motivations to voters. Is a candidate's behavior on the campaign trail informative about their behavior and effort as a legislator? Does it, for example, reveal whether a candidate will be more hard working and legislatively active? Using evidence from the European Parliament we show that campaign activity prior to the election is not related to policy-seeking behavior in the legislature post-election. The finding also holds in two national-level settings and across a variety of measures of legislative effort. Those who campaign harder do seem more likely to win the election, but campaign effort seems to provide a poor guide to what the winner does once elected.

Stefan Müller and Michael Jankowski. 2019. “Do Voters Really Prefer More Choice? Determinants of Support for Personalised Electoral Systems.” Journal of Elections, Public Opinion and Parties 29(2): 262–281.

Which voters prefer having more choice between parties and candidates in an election? To provide an answer to this question, we analyse the case of a radical change from a closed-list PR system to a highly complex open-list PR system with cumulative voting in the German states of Bremen and Hamburg. We argue that the approval of a personalised electoral system is structured in similar ways as support for direct democracy. Using representative surveys conducted prior to all four state elections under cumulative voting in 2011 and 2015, we analyse which individual factors determine the approval, disapproval or indifference towards the new electoral law. The results indicate that younger voters as well as supporters of left parties are much more likely to support a personalised electoral system. In contrast to previous studies, political interest only has an impact on the indifference towards the electoral system. More generally, our results show that a large proportion of voters does not appreciate personalised preferential electoral systems which seems to be a result of the complexity and magnitude of choice between parties and candidates.

Kenneth Benoit, Kohei Watanabe, Haiyan Wang, Paul Nulty, Adam Obeng, Stefan Müller, and Akitaka Matsuo. 2018. “quanteda: An R Package for the Quantitative Analysis of Textual Data.” Journal of Open Source Software 3(30): 774.

quanteda is an R package providing a comprehensive workflow and toolkit for natural language processing tasks such as corpus management, tokenization, analysis, and visualization. It has extensive functions for applying dictionary analysis, exploring texts using keywords-in-context, computing document and feature similarities, and discovering multi-word expressions through collocation scoring. Based entirely on sparse operations, it provides highly efficient methods for compiling document-feature matrices and for manipulating these or using them in further quantitative analysis. Using C++ and multi-threading extensively, quanteda is also considerably faster and more efficient than other R and Python packages in processing large textual data.

Shaun Bowler, Gail McElroy, and Stefan Müller. 2018. “Voter Preferences and Party Loyalty under Cumulative Voting: Political Behaviour after Electoral Reform in Bremen and Hamburg.” Electoral Studies 51: 93–102.

Many electoral systems constrain voters to one or two votes at election time. Reformers often see this as a failing because voters' preferences are both broader and more varied than the number of choices allowed. New electoral systems therefore often permit more preferences to be expressed. In this paper we examine what happens when cumulative voting is introduced in two German states. Even when we allow for tactical considerations, we find that the principle of unconstrained choice is not widely embraced by voters, although in practice, too, many seem to have preferences for more than just one party. This finding has implications for arguments relating to electoral reform as well as how to conceive of party affiliations in multi-party systems.

Liam Kneafsey and Stefan Müller. 2018. “Assessing the Influence of Neutral Grounds on Match Outcomes.” International Journal of Performance Analysis in Sport 18(6): 892–905.

The home advantage in various sports has been well documented. So far, we lack knowledge whether playing in neutral venues indeed removes many, if not all, theoretically assumed advantages of playing at home. Analysing over 3,500 senior men’s Gaelic football and hurling matches – field games with the highest participation rates in Ireland – between 2009 and 2018, we test the potential moderating influence of neutral venues. In hurling and Gaelic football, a considerable share of matches is played at neutral venues. We test the influence of neutral venues based on descriptive statistics, and multilevel logistic and multinomial regressions controlling for team strength, the importance of the match, the year, and the sport. With predicted probabilities ranging between 0.8 and 0.9, the favourite team is very likely to win home matches. The predicted probability drops below 0.6 for away matches. At neutral venues, the favourite team has a predicted probability of winning of 0.7. A Coarsened Exact Matching (CEM) approach also reveals very substantive and significant effects for the “treatment” of neutral venues. Overall, neutral venues appear to be an under-utilised option for creating fairer and less predictable competition, especially in single-game knockout matches.

Other Publications

Kohei Watanabe and Stefan Müller. 2020. Quanteda Tutorials.

Current Research

Papers Under Review

Voter Expectations of Government Formation in Coalition Systems: The Importance of the Information Context. European Journal of Political Research: revise & resubmit (with Shaun Bowler and Gail McElroy).

Can voters in multi-party systems predict which coalition will form the government with any degree of accuracy? To date, studies which explore voter expectations of coalition formation have emphasized individual level attributes, such as education, but the context of information that voters experience at the time the coalitions are forming should also be consequential in enabling (or handicapping) voters in forming expectations. We examine the relative effects of individual level attributes (e.g. education, cognitive mobilization) versus contextual factors (e.g. information availability) in 19 German state elections and 3 German general elections between 2009 and 2017. We find that the ease of identifiability of alternative future governments varies significantly across multi-party systems. We find that respondents are more likely to predict governments that they would like to see in office, that have a higher probability of receiving a majority of seats, and that consist of ideologically proximate parties. Combining survey data with a novel indicator of coalition signals, measured through a quantitative text analysis of newspaper coverage, we also find that voters consider positive pre-election coalition signals when predicting the government. Finally, we find that the information environment is much more relevant for correct coalition predictions than individual-level characteristics of respondents. While individual attributes do influence predictive ability, these factors are strongly dominated by the context in which the prediction is taking place. The information environment has by far the largest effect on predicting coalition outcomes. Our results have implications for the literature on strategic voting in multiparty settings, as well as the literature on accountability.

Social Media and Political Agenda Setting. Political Communication: revise & resubmit (with Fabrizio Gilardi, Theresa Gessler, and Maël Kubli).

What is the role of social media in political agenda setting? Digital platforms have reduced the gatekeeping power of traditional media and, potentially, they have increased the capacity of various kinds of actors to shape the agenda. We study this question in the Swiss context by examining the connections between three agendas: the traditional media agenda, the social media agenda of parties, and the social media agenda of politicians. Specifically, we validate and apply supervised machine-learning classifiers to categorize 2.78 million articles published in 84 newspapers, 6,500 tweets posted on official party accounts, and 210,000 tweets posted by politicians on their own accounts from January 2018 until December 2019. We first use the classifier to measure the salience of the four most relevant issues of the period: the environment, Europe, gender equality, and immigration. Then, using a VAR approach, we analyze the relationship between the three agendas. Results show that not only do the traditional media agenda, the social media agenda of parties, and the social media agenda of politicians influence one another but, on balance, they cancel each other out, such that no single agenda drives the debate. There is one important exception: for the environment issue, the social media agenda of parties is more predictive of the traditional media agenda than vice-versa, by a significant difference of two percentage points. These findings underscore how closely different agendas are tied together, but also show how exogenous events both constrain and enable parties to push their specific agendas.

Analyzing the Incumbency Advantage across Contexts: Evidence from 70 Years of Irish Local and General Elections. Electoral Studies: revise & resubmit (with Michael Jankowski).

Do candidates elected in a system using proportional representation profit from an incumbency advantage? Do we observe different incumbency effects in national and local elections? And do high-quality competitors affect the reelection of marginally elected candidates? Analyzing seven decades of Irish local (1942–2019) and general national elections (1937–2020), we reassess the mixed evidence on the incumbency advantage under proportional representation and in national and sub-national elections. Additionally, we exploit the ‘dual mandate’ characteristic of Irish local elections to test whether the presence of national-level politicians in local elections decreases the reelection probability of marginally elected local candidates. By applying the Regression Discontinuity Design, we find that the incumbency advantage is stronger in Irish local than in national elections, and that the bonus on the local level increased over time. Finally, the advantage decreases with the presence of a high-quality list competitor. Results suggest that future research on the incumbency advantage should pay more attention to the impact of contextual factors.

Evidence for the Irrelevance of Irrelevant Events (with Liam Kneafsey).

Do ‘irrelevant events’ affect voting behaviour? Moving beyond the case of the United States, we investigate whether sports results influence political opinions. We match constituency-level election data from Irish general elections between 1922 and 2020 and local elections between 1942 and 2019 with the results of matches in the Gaelic football and hurling championships, the most popular sports in Ireland. A difference-in-differences design does not suggest any relationship between match results of regional teams and support for incumbent candidates or government parties. These findings also hold when applying an ‘unexpected event during survey design’ approach to representative surveys conducted throughout two seasons. Our results have important implications for the literature on retrospective voting, opinion formation, and citizen competence.

Building Research Infrastructures to Study Digital Technology and Politics: Lessons from Switzerland (with Fabrizio Gilardi, Lucien Baumgartner, Clau Dermont, Karsten Donnay, Theresa Gessler, Maël Kubli, and Lucas Leemann).

The effects of digital technology on political processes is an important phenomenon that, due to several structural problems, remains poorly understood. A key problem is the lack of adequate research infrastructures to study digital technology and politics, or the lack of access. We first discuss the challenges many social scientists face and then present the infrastructure we built in Switzerland to overcome them, using COVID-19 as an example. We conclude by discussing seven lessons we learned: automatization is key; avoid data hoarding; outsource some parts of the infrastructure, but not others; focus on substantive questions; share data in the context of collaborations; engage in targeted public outreach; collaboration beats competition. We hope that our experience will be helpful to other researchers pursuing similar goals.

Working Papers

Efficient and Scalable Analysis of Political Text (with Kenneth Benoit, Patrick Chester, and Michael Laver).

Estimating policy positions from political text is a core element in many empirical analyses of political competition. This has traditionally been achieved using classical content analysis, which requires (costly) human experts to read and make judgements about all text in some corpus. Benoit et al. (2016) showed that crowd workers can label political texts as effectively as experts, but much faster and more cheaply. However, crowdsourced text analysis still requires judgements about every sentence in every text by multiple crowd workers, limiting its scalability to large text corpora. Unsupervised machine learning requires human “curation” of texts based on policy content, to allow ex-post human interpretation of results. Supervised machine learning methods, in contrast, leverage a relatively small training set of text labelled by humans, whether experts or crowd workers, to analyze a potentially huge volume of text out of sample, making this a much more scalable research tool. In this paper, we evaluate the effectiveness of different supervised machine learning algorithms using training sets labelled by humans, whether experts or crowd workers, to analyze both party manifestos and legislative speeches. We first replicate a widely used left-right scale derived from classical text analysis by human experts. We then exploit the flexibility crowd sourced labels to estimate "new" policy dimensions. Our results are encouraging, suggesting that supervised machine learning based on limited training data is a viable, fast, cheap and scalable method for analyzing large political text corpora out of sample.

Multimodal Determinants of Voter Impression Formation of Female Political Candidates During Televised Debates (with Constantine Boussalis, Travis G. Coan, and Mirya R. Holman).

Political debates often serve as the most important campaign events. Viewers evaluate politicians not just by what they say, but also via non-verbal cues, including facial displays of emotions and vocal pitch. But candidate characteristics can shape non-verbal cues and voter reactions. We draw on role congruity expectations and focus on how gender shapes the use of and reactions to non-verbal communication via the behavior of the most powerful woman in the world: Angela Merkel. Using four full-length debate videos from all German elections between 2005 and 2017, we employ computer vision, machine learning, and text analysis to extract facial displays of emotion, vocal pitch, and speech sentiment. While Merkel does display emotions generally, she expresses less anger and emotes less over time. We combine second-by-second emotions with continuous responses recorded by live audiences. Controlling for viewers’ political attitudes, we find that voters reward Merkel for happiness expressions, but only when she is the incumbent leader.

The Compass of Irish Politics is Moving to the Left (with Aidan Regan).

It has often been assumed that Ireland is an outlier in comparative politics. It never had a left-right divide in parliament, and for decades, the dominant centrist political parties competed around a centre-right policy agenda. The absence of an explicit left-right divide in party competition and parliament was assumed to mean that Irish voters, on average, occupy centre-right policy preferences. The dominant parties were simply responding to what the average voter wanted. Using the 2020 Irish electoral survey and data from all Irish election studies since 2002, we show that this is no longer the case. The average Irish voter now leans to the centre-left. This self-identification on the left is consistent with policy preferences on taxes, spending, and government interventions to reduce inequality. This left-leaning trend is consistent even when Sinn Féin voters are excluded from the data, or when using a different survey that explicitly explains to respondents the substantive meaning of the left-right dimension. We show who exactly these growing voters are, and whom they are voting for. The paper analyses different theoretical arguments to explain why this leftward shift has taken place, and concludes that it is related to economic conflict and the changing class-based structure of the Irish political economy, and the emergence of Sinn Féin as the main opposition party.

Ongoing Projects

Explaining (In)Congruence Between Politicians’ Campaign Promises and Subsequent Legislative Priorities (with Naofumi Fujimura).

Social Media and Policy Responses to the COVID-19 Pandemic in Switzerland (with Fabrizio Gilardi, Theresa Gessler, and Maël Kubli).

Causes and Electoral Effects of Nostalgic Rhetoric: A Cross-National Analysis of Party Communication (with Sven-Oliver Proksch).

If you would like to get access to the latest version of a paper, feel free to send me an e-mail.


Course Instructor at University College Dublin

Undergraduate Level

Postgraduate Level

Course Instructor at the University of Zurich

Undergraduate Level

Postgraduate Level

Workshop Instructor

Teaching Awards and Qualifications

Text Analysis

Quanteda Initiative

I work as the Documentation Manager and Training Advisor of the Quanteda Initiative (QI), a UK non-profit organisation devoted to the promotion of open-source text analysis software, and co-author of the following R packages:

Teaching Materials for Text Analysis

Below you can find tutorials, cheatsheets, and vignettes I have authored as a member of the Quanteda Initiative.

Introduction to Quantitative Text Analysis

  • Quanteda tutorials: a website with a step-by-step introduction to quantitative text analysis using quanteda designed for workshops on text analysis

Cheat Sheet and Vignettes


Irish Polling Indicator

The Irish Polling Indicator is a joint project with Tom Louwerse. We combine all Irish opinion polls for the Dáil Éireann by Behaviour & Attitudes, Ipsos MRBI, Ireland Thinks, Millward Brown, Panelbase, and Red C Research into daily estimates of public support for the parties. The website of the Polling Indicator provides various visualisations and detailed information on the underlying methods.

The figure below (updated automatically after the release of new polls) summarises the most recent estimates of party support:

Curriculum Vitae

Extensive CV (PDF)

Academic Positions

01.2020– Assistant Professor (Lecturer) and Ad Astra Fellow
University College Dublin
School of Politics and International Relations
Connected_Politics Lab (founding member)
01.2019–06.2020 Senior Researcher (Oberassistent)
University of Zurich, Department of Political Science


09.2015–12.2018 PhD in Political Science
Trinity College Dublin, Department of Political Science
09.2017–05.2018 Postgraduate Certificate in Statistics
Trinity College Dublin, School of Computer Science and Statistics
09.2014–08.2015 Master of Science in Politics and Public Policy
Trinity College Dublin, Department of Political Science
10.2011–06.2014 Bachelor of Arts in Political Science and Sociology
University of Bonn, Department of Political Science and Sociology

Visiting Positions

08.2019–09.2019 Visiting Research Fellow
Kobe University, Graduate School of Law
06.2019–07.2019 Visiting Researcher
Trinity College Dublin, Department of Political Science
05.2018–06.2018 Guest Researcher
EUROLAB at GESIS – Leibniz Institute for the Social Sciences, Cologne

Selected Fellowships and Grants

2016–2019 Government of Ireland Postgraduate Scholarship,
Irish Research Council
2015–2016 Postgraduate Ussher Fellowship,
Trinity College Dublin
2011–2015 Undergraduate and Graduate Fellowship,
German Academic Scholarship Foundation
(Studienstiftung des deutschen Volkes)