The paper considers a voting model where each voter's type is her preference. The type graph for a voter is a graph whose vertices are the possible types of the voter. Two vertices are connected by an edge in the graph if the associated types are "neighbors." A social choice function is locally...

In a voting model where the set of feasible alternatives is a subset of a product set $A = A_1\times\cdots\ldots{}A_m$ of $m$ finite categories, we characterize the set of all strategy-proof social choice functions for three different types of preference domains over $A$, namely for the domains...

This is the first of four articles on the 2025 German federal elections, continuing our analysis of the 2009, 2013, 2017 and 2021 elections. We begin with the 2023/24 electoral reform, which aimed to curb the uncontrolled growth of the Bundestag caused by political developments not envisaged in...

This is the second out of four papers on the 2025 German federal elections continuing our analysis of the 2009, 2013, 2017 and 2021 Bundestag elections. We estimate the policy representation ability of the 29 parties that participated in the 2025 elections and of the 2025 Bundestag. For this...

This is the third out four papers on the 2025 German Bundestag elections continuing our analysis of the 2009, 2013, 2017 and 2021 elections. In particular, this paper contributes to the discussion of the imperfection of the German 2023/24 Electoral reform in [Tangian 2025a]. We show that policy...

This is the last out of four papers on the 2025 German federal elections continuing our analysis of the 2009, 2013, 2017 and 2021 Bundestag elections. First, we apply the model from [Tangian 2022b] to construct the 2025 German political spectrum understood as a contiguous party ordering, i.e.,...

We examine whether anti-establishment outsider movements can leverage education and youth mobilization to build long-run political power. We study the expansion of state-run religious secondary schools in 1970s Türkiye and show that access to these schools catalyzed the emergence of Islamist...

We propose a new single-winner voting system using ranked ballots: Stable Voting. The motivating principle of Stable Voting is that if a candidate A would win without another candidate B in the election, and A beats B in a head-to-head majority comparison, then A should still win in the election...

We consider social decision-making situations where some voters may have a conflict of interest in some social alternatives/applicants to be ranked. Then the accountability of the collective decision process is essential. We extend the standard social welfare function to include the interest...

We propose six axioms concerning when one candidate should defeat another in a democratic election involving two or more candidates. Five of the axioms are widely satisfied by known voting procedures. The sixth axiom is a weakening of Kenneth Arrow’s famous condition of the Independence of...