For any simple voting game (SVG), we consider the question posed in the title from two different points of view as to what voting power means. We also distinguish between blocs imposed by annexation and those formed voluntarily, and present some general theoretical results concerning these...

We explain the issue of the decision rule of the EU’s Council of Ministers. We outline, in as non-technical fashion as we can, the mathematical theory (due to L S Penrose) that addresses this sort of issue. We assess the decision rule prescribed in the Nice Treaty as well as that included in...

We analyse and evaluate three decision rules for the Council of Ministers of the EU, which are prescribed by the `definitive form' of the Treaty of Nice. The first will apply from 2005 to the present 15-member EU, if it will not have been enlarged by then. The second or third will apply to an...

We explain the issue of the decision rule of the EU's Council of Ministers. We outline, in as non-technical fashion as we can, the mathematical theory (due to L S Penrose) that addresses this sort of issue. We assess the decision rule prescribed in the Nice Treaty as well as that included in the...

These are comments on the Symposium `Power Indices and the European Union' in the July 1999 issue of this Journal. We point out several common inter-connected confusions and errors concerning the meaning of voting power. We stress the vital distinction between two different intuitive notions of...

This book is the first of its kind: a monograph devoted to a systematic critical examination and exposition of the theory of a priori voting power. This important branch of social-choice theory overlaps with game theory and is concerned with the ability of members in bodies that make yes or no...

We consider a singular event of the following form: in a simple voting game, a particular division of the voters resulted in a positive outcome. We propose a plausible measure that quantifies the causal contribution of any given voter to the outcome. This measure is based on a conceptual...

We discuss two inter-related puzzling features of the literature on a priori voting power. First, the mathematical model used in virtually all this literature does not recognize abstention as an option distinct from both a 'yes' and a 'no' vote. Second, reallife decision rules of voting bodies -...

We address simple voting games (SVGs) as mathematical objects in their own right, and study structures made up of these objects, rather than focusing on SVGs primarily as co-operative games. To this end it is convenient to employ the conceptual framework and language of category theory. This...