Regression discontinuity designs (RDD) are widely used in the social sciences to estimate causal effects from observational data. Following recent methodological advances, scholars can choose from various RDD estimators for point estimation and inference. This decision is mainly guided by theoretical results on optimality and Monte Carlo simulations because of a paucity of research on the performance of the different estimators in recovering real-world experimental benchmarks. Leveraging exact ties in personal votes in local elections in Colombia and Finland, which are resolved by a random lottery, we assess the performance of various estimators featuring different polynomial degrees, bias-correction methods, optimal bandwidths, and approaches to statistical inference. Using re-running and re-election as outcomes, we document only minor differences in the performance of the various implementation approaches when the conditional expectation function (CEF) of the outcomes in the vicinity of the discontinuity is close to linear. When approximating the curvature of the CEF is more challenging, bias-corrected and robust inference with coverage-error-rate-optimal bandwidths comes closer to the experimental benchmark than more widely used alternative implementations.

Results from cultural evolutionary theory often suggest that social learning can lead cultural groups to differ markedly in the same environment. Put differently, cultural evolutionary processes can in principle stabilise behavioural differences between groups, which in turn could lead selection pressures to vary across cultural groups. Separating the effects of culture from other confounds, however, is often a daunting and sometimes intractable challenge for the working empiricist. To meet this challenge, we exploit a cultural border dividing Switzerland in ways that are independent of institutional, environmental and genetic variation. Using a regression discontinuity design, we estimate discontinuities at the border in terms of preferences related to fertility and mortality, the two basic components of genetic fitness. We specifically select six referenda related to health and fertility and analyse differences in the proportion of yes votes across municipalities on the two sides of the border. Our results show multiple discontinuities and thus indicate a potential role of culture in shaping stable differences between groups in preferences and choices related to individual health and fertility. These findings further suggest that at least one of the two groups, in order to uphold its cultural values, has supported policies that could impose fitness costs on individuals relative to the alternative policy under consideration.

Exploiting the fact that hypertension is diagnosed when a person’s blood pressure reading exceeds a medically specified threshold (90 mmHg for diastolic blood pressure or 140 mmHg for systolic blood pressure), this study estimates the effect of a first-ever hypertension diagnosis on Chinese adults’ alcohol consumption using a two-dimensional regression discontinuity design. Analyzing data on 10,787 adults from the China Health and Nutrition Survey, our estimation reveals that hypertension diagnoses based on diastolic blood pressure readings exert a number of desirable effects. Hypertensive adults’ drinking frequency and the incidence of excessive drinking among them were reduced by 1.2 times/week and 17.9 percentage points, respectively, about three years after the diagnosis. Meanwhile, their beer and Chinese spirits (Baijiu) intakes were reduced by 518.6 ml/week and 194.8 ml/week, respectively. Interestingly, we also found modest evidence that hypertension diagnoses based on diastolic blood pressure readings increase Chinese adults’ wine intake, suggesting a substitution pattern upon hypertension diagnoses. In contrast, based on systolic blood pressure readings, no significant effects of hypertension diagnoses on alcohol consumption were found.

Faced with rising levels of cross-border migration, many countries have extended local voting rights to non-citizen residents. However, empirical evidence indicates that voter turnout among non-naturalized immigrants is lower when compared to citizens. This raises the question of how to explain this difference. A common answer is that the low turnout rates of non-citizen residents are primarily due to the socio-economic composition of this group and the challenges involved in adapting to a new political system. An alternative but less discussed possibility is that the low turnout concerns the nature of the elections. Hence, we examine whether the turnout of non-citizens is hampered because they are only allowed to partake in local elections. Based on a regression discontinuity design (RDD) using Swedish administrative data, we find that turnout could increase by 10–20 percentage points if the voting rights of non-citizens were extended to the national level.

We provide closed-form solutions for measuring electoral closeness of candidates in proportional representation (PR) systems. In contrast to plurality systems, closeness in PR systems cannot be directly inferred from votes. Our measure captures electoral closeness for both open- and closed-list systems and for both main families of seat allocation mechanisms. This unified measure quantifies the vote surplus (shortfall) for elected (nonelected) candidates. It can serve as an assignment variable in regression discontinuity designs or as a measure of electoral competitiveness. For illustration, we estimate the incumbency advantage for the parliaments in Switzerland, Honduras, and Norway.

Many studies exploit close elections in a regression discontinuity framework to identify partisan effects, that is, the effect of having a given party in office on some outcome. We argue that, when conducted on single-member districts, such design may identify a compound effect: the partisan effect, plus the majority status effect, that is, the effect of being represented by a member of the legislative majority. We provide a simple strategy to disentangle the two, and test it with simulations. Finally, we show the empirical relevance of this issue using real data.

A close reading of the literature on radical right parties (RRPs) suggests that these parties erode trust and solidarity in European democracies when they pit ‘the pure people’ against political and legal institutions, elites, and immigrants. I propose the conjecture that RRPs with seats in the national parliament have better conditions for spreading nativist and populist messages that may erode trust and solidarity between a society’s residents, between ethnic groups, and towards its political and legal institutions. To test this research question, I combine nine waves of European Social Survey data from 17 countries and data on national elections spanning the years 1999 to 2020. Two-way fixed effects models estimate that RRPs representation in the national parliament is associated with a reduction in public support for redistribution of ca. 18% of a standard deviation. Additionally, I demonstrate that this inverse relationship runs parallel to growing welfare chauvinistic beliefs and that it is stronger in countries with weak integration policies. Contra theoretical expectations, the radical rights’ political representation has not produced any change in societal levels of anti-immigration attitudes, institutional trust, or social trust. While the findings persist across a wide range of robustness checks and other model specifications, threats to identification in the form of non-parallel pre-trends and unobserved sources of confounding, means that one should be cautious in interpreting the findings in a causal manner.

We study the impact of compulsory voting in Brazil, where voting is mandatory from age 18 to 70 and voluntary for those aged 16, 17 and 70+. Using a survey sample of 8008 respondents, we document voter confusion about how the age criterion applies. Some people falsely believe that what matters is one's age in an election year rather than on Election Day. Next, we perform a regression discontinuity (RD) analysis of compulsory voting among young voters with register-based data from six Brazilian elections (2008–2018). We find that the effect of compulsory voting is seriously underestimated if we focus solely on the discontinuities prescribed by the law. Our findings carry important implications for studies adopting the RD design where knowledge of the cutoff is expected of the units of interest (like those about compulsory voting) and confirm that compulsory voting is a strong institutional arrangement that promotes greater electoral participation.

Regression discontinuity (RD) designs are increasingly common in political science. They have many advantages, including a known and observable treatment assignment mechanism. The literature has emphasized the need for “falsification tests” and ways to assess the validity of the design. When implementing RD designs, researchers typically rely on two falsification tests, based on empirically testable implications of the identifying assumptions, to argue the design is credible. These tests, one for continuity in the regression function for a pretreatment covariate, and one for continuity in the density of the forcing variable, use a null of no difference in the parameter of interest at the discontinuity. Common practice can, incorrectly, conflate a failure to reject evidence of a flawed design with evidence that the design is credible. The well-known equivalence testing approach addresses these problems, but how to implement equivalence tests in the RD framework is not straightforward. This paper develops two equivalence tests tailored for RD designs that allow researchers to provide statistical evidence that the design is credible. Simulation studies show the superior performance of equivalence-based tests over tests-of-difference, as used in current practice. The tests are applied to the close elections RD data presented in Eggers et al. (2015b).

While youth suffrage is widely debated, the causal effects of being eligible to vote on adolescents' political attitudes are less well known. To gain insights into this question, we leverage data from a real-life quasi-experiment of voting at 16 in the city of Ghent (Belgium). We compare the attitudes of adolescents that were entitled to vote with their peers that just fell below the age cut-off. We also examine the effects of the enfranchisement at 18-years-old. While we find an effect of youth enfranchisement on attention to politics, there is no evidence for an effect of enfranchisement on political engagement overall.

Most of the distributive politics literature focuses on how incumbent politicians allocate development resources in the absence of spending rules, and on the politicization of rules when they do determine distribution. What is less clear is whether politically neutral spending rules lead to neutral spending. Using new data on a long-running federal development fund and elections from Pakistan in a regression discontinuity design, the author presents strong evidence that the ruling party manipulated fund distribution to disproportionately benefit its co-partisans and punish the weakest opposition. Considering various factors, partisan bias is the most plausible explanation. These findings are important not only because the purpose of rules-based funds is to prevent politicized distribution but also because they have implications for development patterns and for using such funds to address questions about legislator effort and patronage patterns within constituencies, which requires assuming that legislators do receive their share of funds in the first place.