| This page enables you
calculate the Shapley-Shubik power indices for a large weighted voting body of any size, for
example the
analysis of power in a shareholder voting game for a public corporation
with many hundreds of shareholders, or a large international
organisation such as the IMF or World Bank. It uses Leech's
modification
of the approximation method of multilinear extensions of Guillermo
Owen. It can be applied to voting bodies of any size both in terms of
number
of players and in terms of votes. The voting weights do not have to be
integers. The method uses a combination of direct enumeration and approximation based on a probabilistic voting model. It is necessary to divide the players into "major" and "minor". The "major" players are a small number including the largest and the "minor" ones are the remainder. The algorithm trades off speed against accuracy: the larger is the number of "major" players assumed the slower and more accurate the algorithm. In practice, in most applications, the number of major players need not be greater than 10. The players must be arranged in decreasing order of the size of their respective weights. References: Shapley and Shubik (1954), Leech (2003), Owen (1972, 1995). |
Data Input for ssmmleEnter your data in the
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(The
numbers
are an example which can be overwritten.) |