Abstract
We investigate the computational aspects of safe manipulation, a new model of coalitional manipulation that was recently put forward by Slinko and White [10]. In this model, a potential manipulator v announces how he intends to vote, and some of the other voters whose preferences coincide with those of v may follow suit. Depending on the number of followers, the outcome could be better or worse for v than the outcome of truthful voting. A manipulative vote is called safe if for some number of followers it improves the outcome from v’s perspective, and can never lead to a worse outcome. In this paper, we study the complexity of finding a safe manipulative vote for a number of common voting rules, including Plurality, Borda, k-approval, and Bucklin, providing algorithms and hardness results for both weighted and unweighted voters. We also propose two ways to extend the notion of safe manipulation to the setting where the followers’ preferences may differ from those of the leader, and study the computational properties of the resulting extensions.
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References
Bartholdi III, J.J., Tovey, C.A., Trick, M.: The computational difficulty of manipulating an election. Social Choice and Welfare 6, 227–241 (1989)
Bartholdi III, J.J., Orlin, J.B.: Single transferable vote resists strategic voting. Social Choice and Welfare 8(4), 341–354 (1991)
Conitzer, V., Sandholm, T., Lang, J.: When ere elections with few candidates hard to manipulate? J. ACM 54, 1–33
Faliszewski, P., Hemaspaandra, E., Schnoor, H.: Copeland voting: ties matter. In: AAMAS 2008 (2008)
Garey, M.R., Johnson, D.S.: Computers and Intractability: A Guide to the Theory of NP-Completeness. W.H. Freeman, New York (1979)
Gibbard, A.F.: Manipulation of voting schemes: a general result. Econometrica 41, 597–601 (1973)
Moulin, H.: Choice functions over a finite set: a summary. Social Choice and Welfare 2, 147–160 (1985)
Papadimitriou, C.: Computational Complexity. Addison-Wesley, Reading (1994)
Satterthwaite, M.A.: Strategy-proofness and Arrow’s conditions: existence and correspondence theorems for voting procedures and social welfare functions. Journal of Economic Theory 10, 187–217 (1975)
Slinko, A., White, S.: Non-dictatorial social choice rules are safely manipulable. In: COMSOC 2008 (2008)
Xia, L., Zuckerman, M., Procaccia, A.D., Conitzer, V., Rosenschein, J.S.: Complexity of unweighted coalitional manipulation under some common voting rules. In: IJCAI 2009 (2009)
Zuckerman, M., Procaccia, A.D., Rosenschein, J.S.: Algorithms for the coalitional manipulation problem. Artificial Intelligence 173(2), 392–412 (2009)
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Hazon, N., Elkind, E. (2010). Complexity of Safe Strategic Voting. In: Kontogiannis, S., Koutsoupias, E., Spirakis, P.G. (eds) Algorithmic Game Theory. SAGT 2010. Lecture Notes in Computer Science, vol 6386. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-16170-4_19
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DOI: https://doi.org/10.1007/978-3-642-16170-4_19
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