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
Ipower (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.

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