Thomas J. Leeper's research while affiliated with The London School of Economics and Political Science and other places

Publications (34)

Article
Full-text available
How do votes in direct democratic ballots translate into policy preferences about future outcomes and affect the perceived legitimacy of those outcomes? This article examines these questions in the context of sovereignty referendums: specifically, the 2016 referendum on British membership of the European Union (EU). While the referendum result gave...
Article
Mass media are frequently cited as having the potential to inform the public, raising knowledge levels and reducing political knowledge gaps between citizens. But media are also seen as a force for segmentation, disengagement, and widening differences between citizens. If media have no effect on political knowledge, gaps between the engaged and dis...
Article
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The nature of democratic governance is intimately connected with how citizens respond to candidate position taking. But when will a generally uninformed public base its vote choices on candidate positions? Since Converse scholars have argued that citizens should place greater weight on candidate positions on issues they consider personally importan...
Article
Studying Identities with Experiments: Weighing the Risk of Posttreatment Bias Against Priming Effects – Corrigendum - Samara Klar, Thomas Leeper, Joshua Robison
Article
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A well-functioning democracy requires a degree of mutual respect and a willingness to talk across political divides. Yet numerous studies have shown that many electorates are polarized along partisan lines, with animosity towards the partisan out-group. In this article, we further develop the idea of affective polarization, not by partisanship, but...
Chapter
This chapter begins by reviewing the strengths and weaknesses of various approaches for obtaining samples of intersectional identity groups, and then provides some empirical evidence for the viability of general population samples for providing large numbers of respondents from intersectional identity groups. Purposive sampling can be thought of as...
Article
Political scientists rely heavily on survey research to gain insights into public attitudes and behaviors. Over the past decade, survey data collection has moved away from personal face-to-face and telephone interviewing towards a model of computer-assisted self-interviewing. A hallmark of many online surveys is the prominent display of the survey’...
Article
Scholars from across the social sciences argue that identities – such as race, ethnicity, and gender – are highly influential over individuals’ attitudes, actions, and evaluations. Experiments are becoming particularly integral for allowing identity scholars to explain how these social attachments shape our political behavior. In this letter, we dr...
Article
Conjoint analysis is a common tool for studying political preferences. The method disentangles patterns in respondents’ favorability toward complex, multidimensional objects, such as candidates or policies. Most conjoints rely upon a fully randomized design to generate average marginal component effects (AMCEs). They measure the degree to which a g...
Article
Rising rates of nonresponse are one of the most-debated issues in contemporary survey research. While early survey research regularly achieved response rates close to 100 percent, contemporary telephone interviewing methods in the United States regularly obtain response rates below 10 percent, due to a mix of noncontact and refusals. Existing resea...
Article
Full-text available
Conjoint analysis is a common tool for studying political preferences. The method disentangles patterns in respondents' favorability toward complex, multidimensional objects, such as candidates or policies. Most conjoints rely upon a fully randomized design to generate average marginal component effects (AMCEs). These measure the degree to which a...
Article
Full-text available
Immigration is highly salient for voters in Europe and the United States and has generated considerable academic debate about the causes of preferences over immigration. This debate centers around the relative influences of sociotropic or personal economic considerations, as well as non-economic threats. We provide a test of the competing egocentri...
Article
The extent to which survey experiments conducted with nonrepresentative convenience samples are generalizable to target populations depends critically on the degree of treatment effect heterogeneity. Recent inquiries have found a strong correspondence between sample average treatment effects estimated in nationally representative experiments and in...
Article
The early part of an academic career frequently entails processes of social identification: am I an Americanist, a comparativist, a theorist, or an international relations-ist (is that a word?); a positivist, a constructivist, or something else; a “quant” or a “qual”; a pluralist, a Perestroikan, an experimentalist; a teacher, researcher, pundit, “...
Article
How attitudes change and affect behavior depends, in large part, on their strength. Strong attitudes are more resistant to persuasion and are more likely to produce attitude-consistent behavior. But what influences attitude strength? In this article, we explore a widely discussed, but rarely investigated, factor: an individual's political discussio...
Article
This article introduces the use of the Amazon Mechanical Turk (MTurk) crowdsourcing platform as a resource for R users to leverage crowdsourced human intelligence for preprocessing “messy” data into a form easily analyzed within R. The article first describes MTurk and the MTurkR package, then outlines how to use MTurkR to gather and manage crowdso...
Article
Ecological validity is vital to experimental research because designs that are too artificial may not speak to any real-world political phenomenon. One such concern is treatment self-selection: if individuals in the real world self-select treatments, such as political communications, how well does the sample average treatment effect estimate the ef...
Article
Survey experiments have become a central methodology across the social sciences. Researchers can combine experiments’ causal power with the generalizability of population-based samples. Yet, due to the expense of population-based samples, much research relies on convenience samples (e.g. students, online opt-in samples). The emergence of affordable...
Article
According to democratic theory, citizens should have a set of well-defined, valenced opinions. Yet evidence suggests that individuals vary in chronic evaluative tendencies, with some processing information in an online fashion, spontaneously becoming opinionated about whatever they encounter and recalling summary evaluations easily. Individuals low...
Article
Reproducible research and data archiving are increasingly important issues in research involving statistical analyses of quantitative data. This article introduces the dvn package, which allows R users to publicly archive datasets, analysis files, codebooks, and associated metadata in Dataverse Network online repositories, an open-source data archi...
Article
If nothing else, democratic politics requires compromise. Mass polarization, where citizens disagree strongly and those disagreements magnify over time, presents obvious threats to democratic well-being. The overwhelming presumption is that if polarization is occurring, a substantial portion of it is attributable to the fragmentation attendant an i...
Article
A key characteristic of democratic politics is competition between groups, first of all political parties. Yet, the unavoidably partisan nature of political conflict has had too little influence on scholarship on political psychology. Despite more than 50 years of research on political parties and citizens, we continue to lack a systematic understa...
Article
Full-text available
Does rhetoric highlighting social norms or mentioning science in a communication affect individuals’ beliefs about global warming and / or willingness to take action? We draw from framing theory and collective-interest models of action to motivate hypotheses that are tested in two large web-based survey-experiments using convenience samples. Our re...
Article
To what extent are groups selectively exposed to news that affects their self-interest? We theorize that having an interest at stake in an issue increases the importance of related information, promoting selective exposure to politics. The framework we develop generates hypotheses we test with data from 29 U.S. public opinion surveys conducted betw...
Article
Full-text available
Public opinion matters, both as a central element of democratic theory and as a substantive foundation for political representation. The origins and nature of public opinion have long attracted the attention of social scientists. Yet a number of questions remain; among the more perplexing is whether–and under what conditions–public opinion is stabl...
Article
Full-text available
A long acknowledged but seldom addressed problem with political communication experiments concerns the use of captive participants. Study participants rarely have the opportunity to choose information themselves, instead receiving whatever information the experimenter provides. We relax this assumption in the context of an over-time framing experim...
Article
Research on political communication effects has enjoyed great progress over the past 25 years. A key ingredient underlying these advances is the increased usage of experiments that demonstrate how communications influence opinions and behaviors. Virtually all of these studies pay scant attention to events that occur prior to the experiment—that is,...
Article
Full-text available
A long acknowledged by seldom addressed problem with political communication experiments concerns the use of captive participants. Study participants rarely have the opportunity to choose information themselves, instead receiving whatever information the experimenter provides. We relax this assumption in the context of an over-time framing experime...

Citations

... A second limitation is that the 10% response rate for the online brochure is slightly lower than the range of response rates from mail surveys of expected responses to hurricanes-24.6% from the Texas coastal evacuation expectations survey (Lindell et al. 2001) and 23.3% from the Valley Study Area coastal evacuation expectations mail survey ). However, this response rate is consistent with the response rates from mail surveys (Leeper 2019) and some other hazards surveys (e.g., 8% in Jiang et al. 2021), but higher than the response rates for web-based hurricane surveys-2% for Martín et al. (2020) and 1% for Lindell et al. (2020). The similarly low response rates for the Internet surveys suggest that people may be reluctant to log in to unfamiliar websites for fear of having malware surreptitiously downloaded onto their devices. ...
... Therefore, a tight referendum result can appear illegitimate to those on the losing side in a way that a close election defeat (supposing that the relevant rules were known and adhered to) is not viewed as illegitimate by the losers. Hobolt et al., (2022) and Matsusaka (2020, Chap. 12) study the issue of the Brexit referendum and political legitimacy. ...
... While such designs have certain advantages such as straightforward causal identification, they ignore a crucial aspect of our media environment: people's discretion over their individual media diet and the information they decide to access. There are notable examples of research in related areas that directly address selective exposure as part of their experimental designs-such as recent work on media hostility (Arceneaux et al., 2012), persuasion (De Benedictis-Kessner et al., 2019), and political knowledge (Leeper, 2020). To our knowledge, however, no experimental study on misinformation corrections to date takes similar steps to account for endogenous media choice. ...
... 4.2. Dependent variable: Affective polarization at the regional level Affective polarization has been measured in various ways, using feeling thermometer ratings (Iyengar et al., 2019;Wagner, 2020), traits ratings (Iyengar et al., 2012;Levendusky, 2018), trust (Westwood et al., 2018), opinion-based groups (Hobolt et al., 2021) or social distance measures; albeit the latter has been characterized as less consistent (Druckman & Levendusky, 2019). Thermometer ratings, using survey data asking respondents to evaluate parties or partisans on a 0-100 scale, are the most common tools used in the literature. ...
... Future research, however, should examine a broader range of issues that bring different ideologies to the fore and appeal to different populations. Fourth, since we presented respondents with multiple cases, we did not ask credibility questions about each post to avoid priming respondents about the intentional misleading/false character of the message (Klar et al., 2020). However, we acknowledge that belief in misinformation is a valid factor for researching the willingness behind the dissemination of misinformation online. ...
... In the purposive sampling technique, the experts were selected deliberately and not randomly. Furthermore, in the purposive sampling technique, only the experts who are readily approachable and interested to participate in the study were selected (Klar and Leeper, 2019). These experts were selected based on the following qualifications: 1) must have at least 5 years of working experience in the industry; 2) must have a minimum bachelor's degree; 3) must be at the supervisor position level. ...
... The current study adopted a populationbased discrete choice experiment with a randomized conjoint design, that is, conjoint experiment. Conjoint analysis was initially developed in marketing research (Cattin and Wittink, 1982;Green et al., 2001;Green and Rao, 1971;Green and Srinivasan, 1990), but later expanded as a causal inference method with randomized designs in political science (Clayton et al., 2021;Cuesta et al., 2021;Leeper et al., 2020). Among the conjoint analysis studies, an experiment on public preferences to admit immigration to the US (Hainmueller and Hopkins, 2015) inspired this study to analyze public attitudes about inbound travelers' entry into the host country. ...
... This also implies that we do not follow the standard approach in conjoint experiments and do not estimate Average Marginal Component Effects (AMCE; Hainmueller et al., 2014) or Marginal Means (MMs; Leeper et al., 2020). Instead, we estimate logistic regressions in which the dependent variable is 1 if a respondent selected the illiberal politician and 0 otherwise. ...
... [107], and the interaction between the small number of items may reduce the capitalization of chance. However, the optimal results need to be evaluated for safe generalization [108,109]. ...
... And, while there is some correspondence between their choices and what they explicitly mention using, it is by no means perfect. These results largely mirror findings in other literatures regarding the introspective power of individual voters, notably those finding an extremely limited role of subjective "issue importance" in the impact of particular issue positions on vote choice (Leeper & Robison, 2020). Content courtesy of Springer Nature, terms of use apply. ...