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holds, taking special attention when coalitions ap-
pears. In this vein, we have implemented the exten-
sion of Shapley-Shubik and Banzhaf power indices
with coalitions. We have also studied more real vot-
ing systems in deep.
For our future work we are also planning on ex-
tending the considered definitions and algorithms. It
could express multiple alternatives (as abstention) be-
tween input options, voting likeness (two parties with
opposed ideologies are less likely to vote the same),
and try to put both concepts together.
We also plan to improve the complexity of our
algorithm (by the way, all of them are NP-Hard) us-
ing approximation methods for computing power in-
dices (Fatima et al., 2012; Bachrach et al., 2010) and
another methods (Alonso-Meijide and Bowles, 2005).
ACKNOWLEDGEMENTS
X. Molinero has been partially supported by funds
from the Spanish Ministry of Economy and Com-
petitiveness (MINECO) and the European Union
(FEDER funds) under grants MTM2015-66818-P
(VOTA-COOP) and MDM-2014-044 (BGSMath).
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