What are the effects of reason-giving on political attitudes? Both political philosophers and political scientists have speculated that defending proposals with reasons may change voters’ preferences. However, while models of attitude formation predict that the explicit justification of one’s political views may result in attitudes that are more ideologically consistent, less polarized, and more stable, empirical work has not assessed the connection between reason-giving and attitudes. Implementing a survey experiment in which some respondents provide reasons before stating their opinions on six issues in UK politics, I find that reason-giving has very limited effects on the constraint, stability, or polarization of the public’s political attitudes. These findings have important implications for our understanding of deliberative conceptions of democracy – in which reason-giving is a central component – as well as for our understanding of the quality of voters’ political opinions.

Intergroup attitudes and identity ties can shape foreign policy preferences. Anti-Muslim bias is particularly salient in the USA and the UK, but little work assesses whether this bias generalizes to other countries. We evaluate the extent of anti-Muslim bias in foreign policy attitudes through harmonized survey experiments in thirteen European countries (N=19,673). Experimental vignettes present factual reports of religious persecution by China, counter-stereotypically depicting Muslims as victims. We find evidence of anti-Muslim bias. Participants are less opposed to persecution and less likely to support intervention when Muslims, as opposed to other religious groups, are persecuted. However, this bias is not present in all countries. Exploratory analyses underscore that pre-existing intergroup attitudes and shared group identity moderate how group-based evaluations shape foreign policy attitudes. We provide extensive cross-national evidence that anti-Muslim bias is country-specific and that social identity ties and intergroup attitudes influence foreign policy preferences.

All regimes require supporters to govern and survive. We discuss the concept of a ‘regime support group’ and present and validate measures from an extensive dataset recording different features of such groups. This Regime Support and Opposition Groups (ReSOG) dataset covers approximately 2,000 political regimes from almost 200 countries, across 1789–2020. Drawing on the knowledge of about 1,000 country experts, we estimate the size and main geographical location of regime support coalitions and key opposition actors. We also map the social basis of regime support coalitions and opponents, using a 14-category scheme covering various social groups. These data provide a unique quantitative history of the social underpinnings of regimes in the modern era. Using them, we show and discuss the broadening of support coalitions over time, especially in autocracies, the rise of major urban groups, and the relative decline of rural elites in politics, globally.

A perennial issue of survey research is that some participants do not answer all questions. Interactive follow-up requests are a novel approach to this problem. However, research on their effectiveness is scarce. I present the most comprehensive study yet on the effects of interactive requests on item non-responses. Theoretically, I outline different pathways whereby follow-up requests may effectively increase response rates and improve data quality: reminding, motivating, instructing, monitoring, and sanctioning. To test my hypothesis that interactive requests increase item response rates, I conducted an online survey experiment in 2021 on diverse samples of around 3,100 respondents in ten countries worldwide. I find that follow-up requests generally increase response rates, although effects vary by country. Depending on the question and survey design, interactive requests reduce item non-responses by up to 47 per cent across countries, while not adversely affecting data quality. I thus recommend response requests to increase survey data efficiency.

Most political systems consist of multiple layers. Yet datasets are predominantly situated at a single territorial tier, encouraging methodological nationalism, regionalism, and localism. We present three new integrated datasets that include electoral, institutional, ideological, and government composition data on the country and regional level (RD|CED, RED and RPSD). With this data, we cover 337 country elections on the regional level, 2,226 regional elections, and 2,825 regional cabinets in 365 regions of 21 countries from 1941 to 2019, accounting for 800 political parties and their ideological positions. Combined, these data complement and extend existing datasets and facilitate the study of political interaction across levels. Data are available at http://multi-level-cross-level-politics.eu/ or can be accessed through the Havard Dataverse repository. We conclude with an agenda for future cross-level studies.