: The paper presents the probabilistic interpretation of ShapleyShubik index and Banzhaf value and the concept of partial homogeneity structure. Probabilities of being critical can be calculated based on this structure. These probabilities constitute the basis for calculating hybrid power indices, ShapleyShubik index and Banzhaf index being the extreme cases. The paper presents the idea of reconstruction of partial homogeneity structure based on maximum likelihood estimation. This method is based on the same assumptions as hybrid power indices. The method is illustrated by simple heuristic examples and results of analysis of clubs’ voting in 7th term of Sejm – the lower house of the Polish parliament.

This paper aims to present a theoretical concept that allows to investigate decision-making in large and ideologically differentiated bodies. Former models of oceanic games were based on the assumption of equal disposition to cooperate with other players among all voters. It is impossible to hold this assumption in a political reality. The paper develops the concept of "hybrid power indices" for oceanic games. Oceanic games with a partial homogeneity structure are analysed in the paper. The paper is the result of my previous studies of decision-making processes in large assemblies and my efforts in modelling ideological differentiation in political bodies. The paper also shows that presented formal models have solid foundations in classical sociological theories.
The last part presents several convenient and reliable sociological interpretations of the models as well as my plans for future studies using the models described.

The paper presents the concept of reconstructing the ideological space in parliament on the basis of the MPs' voting. Problems arising during the study of ideology in political science were discussed. A concept of "ideology in action" was presented on the basis of the texts of the classics of modern theories of democracy. The concept was presented as contrasted with a traditional concept of ideology as the project of reality. The theoretical andempirical arguments justifying ex-post modeling of the ideological space were presented. The properties and interpretation of the ideological distances defined in accordance with the proposed approach were described. The results of the ideological space in the Sejm of sixth and seventh term were presented. Further analytical capabilities offered by the proposed approach were discussed as well.

The paper presents issues concerning oceanic games. The theorems, which have been discussed, make it possible to apply Shapley-Shubik index to games with infinite number of players. Social interpretations of the presentedmodel have also been shown. Determinants of bandwagon effect observed in social reality have been described in detail. Results of applying oceanic gamesmodel to the analysis of last pre-election competition between Barack Obamaand Hillary Clinton have been presented.