We study a voting model with partial information in which the evaluation of social welfare must be based on information about agents' top choices plus qualitative background conditions on preferences. The former is elicited individually, while the latter is not. The social evaluator is modeled...

We critically discuss the Jefferson/D'Hondt and Webster/Sainte-Laguë methods, which are used to allocate parliament seats to parties in the mixed-member proportional representation systems in Germany, New Zealand, Bolivia, South Africa, South Korea, Scotland and Wales, as well as in the...

Five German leading parties and their coalitions are evaluated from the viewpoint of direct democracy. For this purpose, the positions of the parties on over 30 topical issues are compared with the results of polls of public opinion. The outcomes are summarized in the indices of popularity and...

We consider the problem of how societies should be partitioned into classes if individuals express their views about who should be put with whom in the same class. A non-bossy social aggregator depends only on those cells of the individual partitions the society members classify themselves in....

The outcomes of the 2013 German Bundestag (federal parliament) election are analyzed from the viewpoint of direct democracy. For this purpose, the party positions on 36 topical issues are compared with the results of public opinion polls, and the party and coalition indices of popularity (the...

We conduct an experiment to uncover the reasons behind the typically large behavioral variation and low explanatory power of Nash equilibrium observed in Tullock contests. In our standard contest treatment, only 7% of choices are consistent with Nash equilibrium which is in line with the...

It is proved that, among all restricted preference domains that guarantee consistency (i.e. transitivity) of pairwise majority voting, the single-peaked domain is the only minimally rich and connected domain that contains two completely reversed strict preference orders. It is argued that this...

During the 2016 election to the Student Parliament of the Karlsruhe Institute of Technology (KIT), an experiment on 'The Third Vote' was conducted. The goal was to test an alternative election method based on the idea of internet voting advice applications (VAAs). Under the election method...

In a laboratory experiment, we investigate if groups consisting of two heterogeneous player types (with different marginal contribution costs) can increase their total contributions and payoffs in a threshold public goods game if transfer payments are possible among the players. We find that...

Under the "Third Vote" method, the voters cast no votes but are asked about their preferences on policy issues as declared in the party manifestos (like in voting advice applications, e.g. German Wahl-O-Mat). Then the policy profile of the electorate with the balance of public opinion on every...