Endre Borbáth

Science aspires to be cumulative. Reproducibility efforts strengthen science by testing the reliability of published findings, promoting self-correction, and informing policy-making1. Computational reproductions, whereby independent researchers reproduce the results of published studies, are an essential diagnostic tool2–10. Such efforts should have greater visibility11–16. However, little social science reproduction and robustness has been conducted at scale10,13,17–23. Here we reproduced original analyses and conducted robustness checks of 110 articles that were published in leading economics and political science journals with mandatory data and code sharing policies17,18. We found that more than 85% of published claims were computationally reproducible. In robustness checks, our reanalyses showed that 72% of statistically significant estimates remain significant and in the same direction, and the median reproduced effect size is nearly the same as the originally published effect size (that is, 99% of the published effect size). Additionally, 6 independent research teams examined 12 pre-specified hypotheses about determinants of robustness. Research teams with more experience found lower levels of robustness, and robustness did not correlate with author characteristics or data availability.

Do people change climate-related opinions when they learn that thousands protested? Two survey field experiments tested how turnout at major climate demonstrations shaped politically interested individuals’ views in a German national election. Turnout significantly increased perceived movement efficacy, especially among more involved participants, and potentially increased internal political efficacy. Pro-environmental attitudes and vote intentions remained unchanged. Protest days appear to signal collective capacity rather than drive immediate attitude change.

While party system volatility remains high in Central and Eastern Europe (CEE), less is known about whether electoral competition has become programmatically structured. This paper examines the extent and evolution of programmatic differentiation across four CEE countries, Hungary, Latvia, Poland, and Romania, between the 1990s and 2023. Relying on quantitative content analysis of newspaper coverage during parliamentary election campaigns, it investigates system-level trends in programmatic competition, issue salience, and politicization, as well as party-level patterns of issue salience and entrepreneurship. The results show that programmatic competition is substantial and relatively stable over time, but varies across countries depending on historical legacies and regime trajectories. Cultural conflicts have gained importance, particularly under democratic backsliding. While established parties exhibit routinized and distinct programmatic profiles, new parties expand the issue agenda by politicizing less emphasized conflicts. The findings underscore the continued relevance of cleavage theory for understanding party competition in post-communist Europe.

This symposium examines how European parties mobilize electorally in an era of recurrent crises and rapid political transformation. Building on the updated PolDem dataset, which tracks media coverage of national election campaigns across fifteen European countries from 1972 to 2023, the symposium investigates how issue salience, party positioning, and voter behaviour interact under turbulent conditions. The introduction situates the contributions around three core themes: (1) measuring and comparing party communication across media and manifestos; (2) mapping cross-national and longitudinal variation in political conflict lines; and (3) identifying the drivers of politicization across economic, cultural, and political dimensions. Together, the articles offer an integrated, content-based perspective on campaign dynamics that links short-term issue emphasis to long-term party-system structuration. The collection advances our understanding of how crises reshape electoral competition and democratic representation in Europe.

Political parties in Europe are undergoing profound transformations, with many abandoning traditional brands. This study analyzes party names as indicators of ideological and organizational change, combining an original content analysis across 28 European countries (1945–2023) with two conjoint survey experiments. We find that “nonparty” names have become the majority, reflecting a shift away from ideology toward alternative forms of identification. While movement names appear in wavelike patterns linked to protest cycles, such as after the 2008 Great Recession, nonclassical names are especially prevalent among new, opposition, and right-wing parties. However, a paradox emerges: despite their growing adoption, nonclassical names do not easily yield the anticipated electoral benefits, as new parties seem to gain little from abandoning classical naming conventions. By tracing long-term naming trends and integrating survey-based experimental evidence, we advance debates on party transformation, political branding, and the evolving interplay between electoral and movement politics in contemporary democracies.