Mandated by the Federal Chancellery, the research project VOTO analyses after each federal ballot the voting decisions of Swiss citizens. For this purpose, VOTO surveys about 1500 eligible voters all over Switzerland. VOTO is a joint project of the Swiss Centre of Competence in the Social Sciences FORS, the Centre for Democracy Studies Aarau (ZDA) and the Survey Institute LINK.
The standardized post-vote surveys are the result of the harmonization of the VOTO surveys. A standardization work has been necessary to make a comparison between two items possible. Since the surveys have renamed as “VOTO” instead of “VOX” with the vote of autumn 2016, the standardized surveys start with the VOTO survey no. 1 on the vote of 25.09.2016 and include between 2 and 4 surveys per year, depending on the number of ballots.
The VOTO data combines information from several sources into one file. First, the data integrates and harmonises the most significant variables in the post-vote surveys VOTO. A second type of variable includes specific characteristics of votes and items (i.e. popular initiatives or referendums) such as the date of the vote, the results of each item, participation rates, and the slogans of the federal government. The slogans of the main political parties are also integrated, according to information provided by the database Swissvotes, which is a project from the Année Politique Suisse of the Institute of Political Science of the University of Bern. Finally, the standardized surveys include a third type of variable, created specifically to synthesize certain data and/or to allow comparisons from across the whole range of the available surveys.
In the context of standardized surveys, all data related to a federal vote (that is, a federal voting weekend) is called a "scrutin". The term "projet", meanwhile, refers to a subset of these data, organized in relation to a to one of the specific items of this vote (initiative, referendum, etc.). As a general rule, a “scrutin” will therefore include as many “projects” as there were proposals in the vote data. More specifically, the VOTO surveys offer, for each vote, data in two forms: a “scrutin” file dedicated to the vote as a whole and an individual “project” file for each item submitted for a vote. The cumulative scrutin and project files are also available. The choice of file type is dependent on the analyses which the user would like to carry out.
A whole series of additional information about the VOTO Studies are available on the website https://www.voto.swiss.
