This page enables you to run the program called ipgenf to find power indices exactly by the method of generating functions. The indices computed are those that measure what Felsenthal and Machover (1998) called I-power (power as influence) based on counting all possble voting outcomes or coalitions equally.
The program computes the following for each member:
References: Penrose (1946), Banzhaf (1965), Coleman (1971). The method of generating functions for computing these indices is described in Brams and Affuso (1986); see also Leech (2002e).
This algorithm is very fast and gives exact values for the power indices. It can be used for voting bodies with any number of members and is therefore very powerful. (This particular implementation has a limit of 200 members for convenience.) It has two limitations which make it unsuitable for some situations. (1) It has exponential storage complexity which places limitations on the total voting weight that it can handle: for example it cannot be applied to the IMF Board of Governors where the total weight exceeds 2 million votes. (2) The quota and all the weights must be integers; in some voting bodies where these are percentages or fractions this is a real limitation.
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All numbers must be integers.
are an example and can be overwritten.)