(Go straight to data
input screen.)

This page enables you to
calculate Shapley-Shubik indices exactly and efficiently by the method
of generating functions using the program ssgenf. This method was originally
proposed by
Mann and Shapley (1962, after a suggestion of Cantor). The program
ssgenf is an adaptation of that published by Lambert (1988). References: Shapley and Shubik (1954), Mann and Shapley (1962), Lambert (1988), Lucas (1983), Leech (2002e). This algorithm is very fast and gives exact values for the power indices. It can be used for any number of members (although this particular implementation has a limit of 100). It is therefore very useful for many applications where the Shapley-Shubik index is desired. Its two major disadvantages are: (1) that it has exponential storage complexity which places a limitation on the total number of votes, and the weight for each member, that it can handle: it does not work for the IMF Board of Governors for example where the total number of votes exceeds 2million; and (2) the quota and all the weights must be integers. |

## Data Input for ssgenfEnter your data in the
boxes below.
All numbers must be integers. (The
numbers
are an example and can be overwritten.) |