Elections with Few Voters: Candidate Control Can Be Easy
This addresses election manipulation problems for computational social choice, but it is incremental as it extends existing work to few-voter scenarios.
The paper investigates the computational complexity of candidate control in elections with few voters, focusing on parameterized complexity with the number of voters as a parameter, and finds that the complexity varies more than in many-voter settings.
We study the computational complexity of candidate control in elections with few voters, that is, we consider the parameterized complexity of candidate control in elections with respect to the number of voters as a parameter. We consider both the standard scenario of adding and deleting candidates, where one asks whether a given candidate can become a winner (or, in the destructive case, can be precluded from winning) by adding or deleting few candidates, as well as a combinatorial scenario where adding/deleting a candidate automatically means adding or deleting a whole group of candidates. Considering several fundamental voting rules, our results show that the parameterized complexity of candidate control, with the number of voters as the parameter, is much more varied than in the setting with many voters.