Bribery and Control in Judgment Aggregation1
نویسندگان
چکیده
In computational social choice, the complexity of changing the outcome of elections via manipulation, bribery, and various control actions, such as adding or deleting candidates or voters, has been studied intensely. Endriss et al. [13, 14] initiated the complexity-theoretic study of problems related to judgment aggregation. We extend their results on manipulation to a whole class of judgment aggregation procedures, and we obtain stronger results by considering not only the classical complexity (NP-hardness) but the parameterized complexity (W[2]-hardness) of these problems with respect to natural parameters. Furthermore, we introduce and study the closely related concepts of bribery and control in judgment aggregation. In particular, we study the complexity of changing the outcome of such procedures via control by adding, deleting, or replacing judges.
منابع مشابه
How Hard Is it to Bribe the Judges? A Study of the Complexity of Bribery in Judgment Aggregation
Endriss et al. [1,2] initiated the complexity-theoretic study of problems related to judgment aggregation. We extend their results for manipulating two specific judgment aggregation procedures to a whole class of such procedures, and we obtain stronger results by considering not only the classical complexity (NP-hardness) but the parameterized complexity (W[2]-hardness) of these problems with r...
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