![](bg7.png)
hope these results can lead to further generalizations
and possible developments of systems that better re-
sist such attacks.
It is important to realize that NP-completeness
only addresses the worst-case complexity of a given
problem, and does not take into consideration the dis-
tribution of problems that might be given. Some sim-
ple distributions were considered in (Walsh, 2009;
Friedgut et al., 2008), and it may be of interest to char-
acterize the complexity of more interesting and real-
istic distributions, depending upon the application..
This model also makes the assumption that in a k-
approval election, each voter may vote for any com-
bination of the k candidates independently. We know
that in practice, most elections do not follow this
principle. It may thus be of interest to character-
ize these properties in a more realistic distribution of
voter preferences.
ACKNOWLEDGEMENTS
We wish to offer our special thanks to Dr. E. Hemas-
paandra for pointing out the connection between b-
Edge Cover and elections as well as proofreading.
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