The Borda Count and Dominance Solvable Voting Games
نویسنده
چکیده
We analyse dominance solvability (by iterated elimination of weakly dominated strategies) of voting games with three candidates and provide sufficient and necessary conditions for the Borda Count to yield a unique winner. We find that Borda is the unique scoring rule that is dominance solvable both (i) under unanimous agreement on a best candidate and (ii) under unanimous agreement on a worst candidate and in the absence of a tie. Turning to generalized scoring rules, we find that Approval Voting violates a desirable monotonicity property: a candidate that is the unique dominance solvable winner for some preference profile, may lose the election once she gains further popularity. In contrast, a candidate that is the unique dominance solvable winner under Borda, will always remain so as her popularity increases.
منابع مشابه
Scoring rule voting games and dominance solvability
This paper studies the dominance-solvability (by iterated deletion of weakly dominated strategies) of general scoring rule voting games. The scoring rules we study include Plurality rule, Approval voting, Negative Plurality Rule, Borda rule and Relative Utilitarianism. We provide a classification of scoring rule voting games according to whether the sufficient conditions for dominance solvabili...
متن کاملVoting Systems and Strategic Manipulation: an Experimental Study
This paper presents experiments analyzing the strategic behavior of voters under three voting systems: plurality rule, approval voting, and the Borda count. Strategic behavior is significantly different under each treatment (voting system). Plurality rule leads voters to play in a more sophisticated manner, but not necessarily insincerely, displaying the lowest levels of manipulation. The oppos...
متن کاملWhen are plurality rule voting games dominance-solvable?
This paper studies the dominance-solvability (by iterated deletion of weakly dominated strategies) of plurality rule voting games. For any number of alternatives and at least four voters, we find sufficient conditions for the game to be dominance-solvable (DS) and not to be DS. These conditions can be stated in terms of only one aspect of the game, the largest proportion of voters who agree on ...
متن کاملOn the Complexity of Borda Control in Single-Peaked Elections
Recent research reveals that many NP-hard voting problems in general become polynomial-time solvable in single-peaked elections. In contrast to these results, we prove for the first time that constructive control by adding/deleting votes for Borda are NP-hard even in single-peaked elections. On the other side, we prove that constructive control by adding/deleting votes/candidates for Borda are ...
متن کاملRank Ordering Engineering Designs: Pairwise Comparison Charts and Borda Counts
Designers routinely rank alternatives in a variety of settings using a staple of comparison, the pairwise comparison. In recent years questions have been raised about the use of such comparisons as a means of calculating and aggregating meaningful preference or choice data. Results on voting have been used to argue that the positional procedure known as the Borda count is the best pairwise voti...
متن کامل