The Comparative Study of Electoral Systems (CSES) is a collaborative research project among national election studies around the world. Participating countries and polities include a common module of survey questions in their national post-election studies. The resulting data are collated together along with voting, demographic, district and macro variables into one dataset allowing comparative analysis of voting behavior from a multilevel perspective.
The CSES is published as a free, public dataset. The project is administered by the CSES Secretariat, a joint effort between the Institute for Social Research at the University of Michigan and the GESIS – Leibniz Institute for the Social Sciences in Germany.
Aims and content of the study
The CSES project was founded in 1994 with two major aims. The first was to promote international collaboration between national election studies. The second was to allow researchers to study variations in political institutions, especially electoral systems, and their effects on individual attitudes and behaviors, especially turnout and vote choice.
CSES datasets contain variables at three levels. The first is micro-level variables which are answered by respondents during post-election surveys in each included country. The second is district-level variables that contain election results from the electoral districts that survey respondents are situated in. The third is macro-level variables containing information about the country context and electoral system, as well as aggregate data such as economic indicators and democracy indices. This nested data structure, as depicted in Figure 1, allows for multilevel analysis.
A new thematic module is devised by the CSES Planning Committee every five years. Between the final releases of the complete modules, CSES also disseminates advance releases of datasets periodically, which include partial data for modules that have not been fully released yet. Survey data collection for module 1 was conducted between 1996 and 2001 and focuses on system performance. The module allows investigation of the impact of electoral institutions on citizens’ political cognition and behavior as well as of the nature of political and social cleavages and alignment. Furthermore, it enables research about citizens’ evaluation of democratic institutions and processes. Module 1 includes 39 election studies conducted in 33 countries. Survey data collection for module 2 was conducted between 2001 and 2006 and focuses on accountability and representation. It addresses the contrast between the view that elections are a mechanism to hold government accountable and the view that they are a means to ensure that citizens’ views and interests are properly represented in the democratic process. Module 2 includes 41 election studies conducted in 38 countries. Survey data collection for module 3 was conducted between 2006 and 2011. The module allows investigating the meaningfulness of electoral choices and, accordingly, focuses on a major aspect of electoral research: the contingency in choice of available options. Module 3 includes 50 election studies conducted in 41 countries. Survey data collection for module 4 was conducted between 2011 and 2016 and focuses on distributional politics and social protection. The main topics investigated are voters’ preferences for public policy and the mediating factors of political institutions and voting behavior. Module 4 includes 45 election studies conducted in 39 countries. Survey data collection for module 5 was conducted between 2016 and 2021 and focuses on the electorate's attitudes towards political elites, on the one hand, and towards "out groups", on the other hand. It thus enables research on attitudes and voting behavior in the context of a rise of parties campaigning on anti-establishment messages and in opposition to "out groups". Module 5 includes 56 election studies conducted in 45 countries.
A complete table of all variables available across modules can be found on the CSES website.
CSES also has an Integrated Module Dataset (IMD) which brings together the existing Standalone CSES Modules (CSES Modules 1–4 inclusive) into one longitudinal and harmonized dataset. Variables that appear in at least three Standalone CSES Modules, up to and including CSES Module 5, are eligible for inclusion in IMD with all polities participating in CSES included in the dataset.