@article{MunzertSelb, author = {Munzert, Simon and Selb, Peter}, title = {Can we directly survey adherence to non-pharmaceutical interventions? Evidence from a list experiment conducted in Germany during the early Corona pandemic.}, series = {Survey Research Methods}, volume = {14}, journal = {Survey Research Methods}, number = {2}, doi = {10.18148/srm/2020.v14i2.7759}, pages = {205 -- 209}, abstract = {Self-reports of adherence to non-pharmaceutical interventions in surveys may be subject to social desirability bias. Existing questioning techniques to reduce bias are rarely used to monitor adherence. We conducted a list experiment to elicit truthful answers to the question whether respondents met friends or acquaintances and thus disregarded the social distancing norm. Our empirical findings are mixed. Using the list experiment, we estimate the prevalence of non-compliant behavior at 28\%, whereas the estimate from a direct question is 22\%. However, a more permissively phrased direct question included later in the survey yields an estimate of 47\%. All three estimates vary consistently across social groups. Interestingly, only the list experiment reveals somewhat higher non-compliance rates among the highly educated compared to those with lower education, yet the variance of the list estimates is considerably higher. We conclude that the list experiment compared unfavorably to simpler direct measurements in our case.}, language = {en} } @article{MunzertSelbGohdesetal., author = {Munzert, Simon and Selb, Peter and Gohdes, Anita R. and Stoetzer, Lukas F. and Lowe, Will}, title = {Tracking and Promoting Usage of a COVID-19 Contact Tracing App.}, series = {Nature Human Behavior}, journal = {Nature Human Behavior}, number = {5}, doi = {10.1038/s41562-020-01044-x}, url = {http://nbn-resolving.de/2397-3374}, pages = {247 -- 255}, abstract = {Digital contact tracing apps have been introduced globally as an instrument to contain the COVID-19 pandemic. Yet, privacy by design impedes both the evaluation of these tools and the deployment of evidence-based interventions to stimulate uptake. We combine an online panel survey with mobile tracking data to measure the actual usage of Germany's official contact tracing app and reveal higher uptake rates among respondents with an increased risk of severe illness, but lower rates among those with a heightened risk of exposure to COVID-19. Using a randomized intervention, we show that informative and motivational video messages have very limited effect on uptake. However, findings from a second intervention suggest that even small monetary incentives can strongly increase uptake and help make digital contact tracing a more effective tool.}, language = {en} } @article{SelbMunzert, author = {Selb, Peter and Munzert, Simon}, title = {Estimating Constituency Preferences from Sparse Survey Data Using Auxiliary Geographic Information}, series = {Political Analysis}, volume = {19}, journal = {Political Analysis}, number = {4}, doi = {10.1093/pan/mpr034}, pages = {455 -- 470}, abstract = {Measures of constituency preferences are of vital importance for the study of political representation and other research areas. Yet, such measures are often difficult to obtain. Previous survey-based estimates frequently lack precision and coverage due to small samples, rely on questionable assumptions or require detailed auxiliary information about the constituencies' population characteristics. We propose an alternative Bayesian hierarchical approach that exploits minimal geographic information readily available from digitalized constituency maps. If at hand, social background data are easily integrated. To validate the method, we use national polls and district-level results from the 2009 German Bundestag election, an empirical case for which detailed structural information is missing.}, language = {en} } @incollection{ShikanoMunzertSchuebeletal., author = {Shikano, Susumu and Munzert, Simon and Sch{\"u}bel, Thomas and Herrmann, Michael and Selb, Peter}, title = {Eine empirische Sch{\"a}tzmethode f{\"u}r Valenz-Issues auf der Basis der Kandidatenbeurteilung am Beispiel der Konstanzer Oberb{\"u}rgermeisterwahl 2012}, series = {Jahrbuch f{\"u}r Handlungs- und Entscheidungstheorie}, booktitle = {Jahrbuch f{\"u}r Handlungs- und Entscheidungstheorie}, editor = {Linhart, Eric and Kittel, Bernhard and B{\"a}chtiger, Andr{\´e}}, publisher = {Springer}, address = {Wiesbaden}, isbn = {978-3-658-05007-8}, doi = {10.1007/978-3-658-05008-5_4}, publisher = {Hertie School}, pages = {113 -- 131}, abstract = {Bei der Entwicklung der r{\"a}umlichen Modelle des Parteienwettbewerbs spielt die Valenz eine wichtige Rolle. Trotz der theoretischen Relevanz bleibt die Mess- und Sch{\"a}tzmethode der Valenz unterentwickelt. Angesichts dieser Forschungsl{\"u}cke schl{\"a}gt dieser Beitrag ein statistisches Modell vor, das die gleichzeitige Sch{\"a}tzung der Kandidatenpositionen und der Valenz erm{\"o}glicht. Ein wichtiger Vorzug dieses Modells liegt darin, dass man nur die Kandidatenbeurteilungen per Skalometer ben{\"o}tigt, der in den meisten Umfragedaten verf{\"u}gbar ist. Dieses Modell wird auf Daten angewendet, die in Rahmen der Konstanzer Oberb{\"u}rgermeisterwahl 2012 erhoben wurden.}, language = {de} } @article{MunzertSelb, author = {Munzert, Simon and Selb, Peter}, title = {Measuring Political Knowledge in Web-Based Surveys: An Experimental Validation of Visual Versus Verbal Instruments}, series = {Social Science Computer Review}, volume = {25}, journal = {Social Science Computer Review}, number = {2}, doi = {10.1177/0894439315616325}, pages = {167 -- 183}, abstract = {Does the opportunity to deliver visual instead of verbal stimuli of political knowledge to respondents in web-based surveys make a difference in terms of data quality? For instance, does the presentation of visual knowledge items reduce cheating, that is, looking up the answer via the Web? And do visual and verbal stimuli capture the same underlying construct? To test whether the use of visuals to measure political knowledge effectively makes a difference, we administer a question form experiment in an online survey of the German Longitudinal Election Study. Respondents are randomly assigned to one of two question formats—visual or verbal—and are asked to solve a set of eight questions on political leaders and their offices. The instruments are validated based on nonparametric item response theory and analyses of response latency. While there is no clear evidence for cheating behavior under either of the conditions, both instruments form strong knowledge scales. Results from a regression analysis indicate that the scales provide measures of closely related but not identical concepts.}, language = {en} } @article{SelbMunzert, author = {Selb, Peter and Munzert, Simon}, title = {Forecasting the 2013 German Bundestag Election Using Many Polls and Historical Election Results}, series = {German Politics}, volume = {25}, journal = {German Politics}, number = {1}, doi = {10.1080/09644008.2015.1121454}, pages = {73 -- 83}, abstract = {This article reports on an attempt to forecast the outcome of the 2013 election to the German Bundestag. In contrast to the predominant academic approach to forecast incumbent vote shares from measures of government popularity, economic conditions and other fundamental variables, we entirely relied on data from published trial heat polls. Opposite to common practice in the news media, we did not take isolated polls as election forecasts in their own right. Instead, we used historical data to assess empirically the relationship between polls and election outcomes, and combined extrapolations from current polls in a Bayesian manner. The forecast was published one month ahead of the election. The retrospective evaluation of our method was added after the election. While our method is parsimonious and provides a large lead time, the performance at the 2013 election was underwhelming. We offer additional suggestions how the approach can be improved in future scenarios.}, language = {en} } @article{HerrmannMunzertSelb, author = {Herrmann, Michael and Munzert, Simon and Selb, Peter}, title = {Determining the effect of strategic voting on election results}, series = {Journal of the Royal Statistical Society (Series A)}, volume = {179}, journal = {Journal of the Royal Statistical Society (Series A)}, number = {2}, doi = {10.1111/rssa.12130}, pages = {583 -- 605}, abstract = {Speculations about whether strategic voting made a difference to the outcome of an election regularly whip up the passions of pundits, party strategists, electoral reformers and scholars alike. Yet, research on strategic voting's political effect has been hampered by the scarcity of data on district level party preferences. We propose the use of Bayesian small area estimation to predict district level preferences from just a handful of survey responses per district and comparing these predictions against election results to estimate how many voters switched sides in each district. We apply the approach to estimate how many seats changed hands as a result of strategic voting at the 1997 and 2001 UK general elections. Despite similar rates of strategic voting in both elections, the number of seats that were affected was markedly greater in 1997. Interestingly, the Liberal Democrats turn out to win the most seats because of strategic voting. We also estimate how many votes went in the 'wrong' direction—away from otherwise viable candidates. We validate our results by using journalistic sources and compare them with previous published estimates.}, language = {en} } @article{SelbHerrmannMunzertetal., author = {Selb, Peter and Herrmann, Michael and Munzert, Simon and Sch{\"u}bel, Thomas and Shikano, Susumu}, title = {Forecasting runoff elections using candidate evaluations from first round exit polls}, series = {International Journal of Forecasting}, volume = {29}, journal = {International Journal of Forecasting}, number = {4}, doi = {10.1016/j.ijforecast.2013.02.001}, pages = {541 -- 547}, abstract = {We draw attention to a simple yet underappreciated way of forecasting the outcomes of elections involving two rounds of voting: surveying the voters' candidate evaluations in first round exit polls, poststratifying the sample proportions of reported votes to official first round election returns, and redistributing the votes for eliminated competitors according to their supporters' lower-order preferences among the viable alternatives in round two. We argue that the approach is likely to outperform standard pre-election surveys, due to its better coverage and reduced measurement error, and the possibility of correcting for sample selection. We set out the practical details of the method and demonstrate its usefulness by employing a recent German mayoral election as an empirical case. Thirteen candidates were competing in the first round, while there were six candidates in the decisive second round. The runoff result was forecast two weeks in advance with an average absolute error of less than one percentage point.}, language = {en} } @article{SelbMunzert, author = {Selb, Peter and Munzert, Simon}, title = {Voter overrepresentation, vote misreporting, and turnout bias in postelection surveys}, series = {Electoral Studies}, volume = {32}, journal = {Electoral Studies}, number = {1}, doi = {10.1016/j.electstud.2012.11.004}, pages = {186 -- 196}, abstract = {Figures from postelection surveys often grossly overestimate election turnout. Two distinct phenomena are responsible for this gap: overrepresentation of actual voters and vote misreporting by actual nonvoters among survey respondents. Previous accounts of turnout bias are inconclusive in that they either focus on a single component, or fail to separate between the two. In this paper, we formally decompose turnout bias in election surveys into its constituent parts, assess their empirical prevalence and heterogeneity using an extensive collection of 49 vote validation studies from six countries, and employ Bayesian meta regression techniques to account for cross-study differences. Our results indicate that both election and survey characteristics such as actual voter turnout and survey response rates differentially affect the components of turnout bias. We conclude with a discussion of the threats and potentials of our findings for survey-based comparative electoral research.}, language = {en} } @article{SelbMunzert, author = {Selb, Peter and Munzert, Simon}, title = {Examining a Most Likely Case for Strong Campaign Effects: Hitler's Speeches and the Rise of the Nazi Party, 1927-1933}, series = {American Political Science Review}, volume = {112}, journal = {American Political Science Review}, number = {4}, doi = {10.1017/S0003055418000424}, pages = {1050 -- 1066}, abstract = {Hitler's rise to power amidst an unprecedented propaganda campaign initiated scholarly interest in campaign effects. To the surprise of many, empirical studies often found minimal effects. The predominant focus of early work was on U.S. elections, though. Nazi propaganda as the archetypal and, in many ways, most likely case for strong effects has rarely been studied. We collect extensive data about Hitler's speeches and gauge their impact on voter support at five national elections preceding the dictatorship. We use a semi-parametric difference-in-differences approach to estimate effects in the face of potential confounding due to the deliberate scheduling of events. Our findings suggest that Hitler's speeches, while rationally targeted, had a negligible impact on the Nazis' electoral fortunes. Only the 1932 presidential runoff, an election preceded by an extraordinarily short, intense, and one-sided campaign, yielded positive effects. This study questions the importance of charismatic leaders for the success of populist movements.}, language = {en} }