Computing Power Indices in Weighted Majority Games with Formal Power Series
摘要
In this paper, we propose fast pseudo-polynomial-time algorithms for computing power indices in weighted majority games. We show that we can compute the Banzhaf index for all players in \(\textrm{O}(n+q\log (q))\) time, where n is the number of players and q is a given quota. Moreover, we prove that the Shapley–Shubik index for all players can be computed in \(\textrm{O}(nq\log (q))\) time. Our algorithms are faster than existing algorithms when \(q=2^{o(n)}\) . Our algorithms exploit efficient computation techniques for formal power series.