Internet-based scenarios, like co-working, e-freelancing, or crowdsourcing, usually need supporting collaboration among several actors that compete to service tasks. Moreover, the distribution of service requests, i.e., the arrival rate, varies over time, as well as the service workload required by each customer. In these scenarios, coalitions can be used to help agents to manage tasks they can...

The Banzhaf index and the Shapley-Shubik index are the best-known and the most used tools to measure political power of voters in a voting system. Most methods to calculate these power indices are based on counting winning coalitions, in particular those coalitions a voter is decisive for. We present a new combinatorial formula to calculate both indices solely using the set of minimal winning c...

The Penrose-Banzhaf index and the Shapley-Shubik index are the best-known and the most used tools to measure political power of voters in simple voting games. Most methods to calculate these power indices are based on counting winning coalitions, in particular those coalitions a voter is decisive for. We present a new combinatorial formula how to calculate both indices solely using the set of m...

Policy-making is a dynamic process in which policies can be changed in each period but continue in the absence of new legislation. We study a dynamic legislative bargaining game with an endogenous status quo where in each period a dollar is allocated with a proposal voted against the allocation in the previous period. We characterize for any initial status quo a class of simple Markov perfect e...

Tarsal coalitions (TC) are congenital abnormal connections of the rearfoot bones. They occur in 1 to 13 % all population. The article deals with features clinical and instrumental diagnosis TC according literature. main manifestations pain syndrome subtalar area, rigid flat foot; peroneal spastic foot is possible. Radiographic imaging includes direct indirect signs. To verify bone coalition, co...

I study the existence of Nash-stable and individually stable coalition structures in hedonic coalition formation games, where a coalition structure is a partition of the players, and players strictly rank the coalitions to which they belong. The hedonic coalition formation game in which all coalitions are feasible is viewed as a general model, and more specific models, such as the marriage and ...