A high court has to decide whether a law is constitutional, un- constitutional, or interpretable. The voting system is runoff. Runoff voting systems can be interpreted both, as social choice functions or as mechanisms. It is known that, for universal domains of preferences, runoff voting systems...

We analyze the problem of choosing the w contestants who will win a competition within a group of n w competitors when all jurors commonly observe who the w best contestants are, but they may be biased. We study conditions on the configuration of the jury so that it is possible to induce the...

We analyze the problem of a jury choosing the winner from a set of agents when the identity of the deserving winner is common knowledge amongst the jurors but each juror is biased in favor of one di¤erent agent. We propose a simple and natural mechanism that implements the socially optimal rule...

In this paper, we study individual incentives to report preferences truthfully for the special case when individuals have dichotomous preferences on the set of alternatives and preferences are aggregated in form of scoring rules. In particular, we show that (a) the Borda Count coincides with...

The chosen tournament format has a fundamental impact on the popularity and success of a sport. Efficiency of a format describes how well it can reproduce the real but hidden power ranking of the participants. We compare the efficiency of the formats of two individual sports that share similar...

We study the problem of a society choosing a subset of new members from a finite set of candidates (as in Barber?Sonnenschein, and Zhou, 1991). However, we explicitly consider the possibility that initial members of the society (founders) may want to leave it if they do not like the resulting...

The chosen tournament format has a fundamental impact on the popularity and success of a sport. Efficiency of a format describes how well it can reproduce the real but hidden power ranking of the participants. We compare the efficiency of the formats of two individual sports that share similar...

Polish Abstract: 20 maja 2016 roku weszła w życie nowelizacja ustawy Prawo o stowarzyszeniach. Wprowadza ona istotne reformy w funkcjonowaniu stowarzyszeń w Polsce. Największe zmiany odnoszą się do stowarzyszeń zwykłych o niepełnej (ułomnej, ustawowej) osobowości prawnej. Zmiany są...