The cost-benefi t analysis has a long history, especially in the United States. Its widespread use in Europe is connected with the requirements of the European Commission, the European Union, that preceded the selection of projects fi nanced from EU funds or was the basis for the evaluation of projects. The aim of this article is to draw attention to the social aspects of this analysis, as they conducted limited analysis to the economic and financial aspects.

The article proposes a new type of statistical dependence. Statistical independence of this type means the identity of the frequency order of category choices in all groups. The compatibility between choices will be assessed by means of a diversity measure. A new measure of statistical dependence, its properties and interpretation will be specifi ed.

Decision making in international organizations is a multistage and complex process. This paper is confi ned however only to one but the most important stage, either the voting on a one proposal, which may be accepted or rejected, or the choice between two alternative proposals. This seemingly simple, dichotomous decision can be made by many different methods of voting, i.e. simple majority; absolute majority; qualifi ed majority; voting with quorum; weighted voting; voting with a possibility of veto etc. These methods differ in their properties: equal vs. unequal treatment of the participants of decision-making assembly; the manner of respecting of minority rights; equal vs. unequal treatment of possible decisions; sensitiveness to changes of decisions of particular participants; effectiveness and other. These properties express postulates: anonymity; semi-duality; citizen sovereignty; monotonicity and strong monotonicity; unanimity, unrestricted domain etc. Some of these properties exclude the other. The choice of the particular method of voting means an acceptation of some postulates and a resignation from the other postulates.

Point system is a method of goods division which belongs to so called local justice. It has an application to deterministic allocation of indivisible units of a homogeneous good among a set of agents demanding one unit of the good each. Desirable, normative criteria of this method are presented, especially monotonicity and its consequences. The way of formation of a point system has a basic importance for the properties of goods division. Some examples of applications of a point system are presented.

Social choice theory is essentially about the constraints upon effective mechanisms for implementing desirable states of a society or a group, given the preferences and utilities of its members. Social choice theory is also, and much more generally, a conceptual examination of normative theories of society – theories that characterize what it is for state of affairs to be better from the social point of view. Social choice methods have different aims, for example democratic decision-making, epistemic decision-making, respecting individual rights of persons and groups, just distribution of goods. They are justified by the sets of postulates, which represent different basic social values.

An indispensable feature of a federation is autonomy of the parts of the federation. Federation systems differ in a degree of autonomy. Respecting group rights in social decision-making in federations can be in conflict with the Pareto optimality principle. It is the essence of the so-called federal paradox. The paradox of federalism, unlike the liberal paradox, i.e., a similar potential inconsistency between respecting individual rights and the efficiency of social decisions, has not yet been fully analyzed. In this paper, after presentation of the liberal paradox, well described in the literature, we present a formal characterization of the federal paradox. Moreover, some other problems connected to decision-making in federations are discussed.