A comparison of the Dodgson method and the Copeland rule
نویسنده
چکیده
This paper compares binary versions of two well−known preference aggregation methods designed to overcome problems occurring from voting cycles, Copeland’s (1951) and Dodgson’s (1876) method. In particular it will first be shown that the Copeland winner can occur at any position in the Dodgson ranking. Second, it will be proved that for some list of individual preferences over the set of alternatives, the Dodgson ranking and the Copeland ranking will be exactly the opposite, i.e. maximally different. I am grateful to Nick Baigent for his very helpful comments. Citation: Klamler, Christian, (2003) "A comparison of the Dodgson method and the Copeland rule." Economics Bulletin, Vol. 4, No. 8 pp. 1−7 Submitted: October 21, 2002. Accepted: February 7, 2003. URL: http://www.economicsbulletin.com/2003/volume4/EB−02D70014A.pdf
منابع مشابه
Generalization of Dodgson's "Virtual Center" Method; an Efficient Method for Determinant Calculation
Charles Dodgson (1866) introduced a method to calculate matrices determinant, in asimple way. The method was highly attractive, however, if the sub-matrix or the mainmatrix determination is divided by zero, it would not provide the correct answer. Thispaper explains the Dodgson method's structure and provides a solution for the problemof "dividing by zero" called "virtua...
متن کاملDodgson's Rule Approximations and Absurdity
With the Dodgson rule, cloning the electorate can change the winner, which Young (1977) considers an “absurdity”. Removing this absurdity results in a new rule (Fishburn, 1977) for which we can compute the winner in polynomial time (Rothe et al., 2003), unlike the traditional Dodgson rule. We call this rule DC and introduce two new related rules (DR and D&). Dodgson did not explicitly propose t...
متن کاملComparison of fine needle aspiration and direct skin smear in the diagnosis of acute cutaneous leishmaniasis: polymerase chain reaction as a reference method
Background: Accurate diagnosis of cutaneous leishmaniasis wouldavoid unnecessary treatment and scar formation. Direct smear isthe most common method for the diagnosis of this disease but itsnegative result could not rule out the infection; so, the need formore sensitive methods is obvious. We conducted this study tocompare the efficiency of direct skin smear with smears preparedby fine needle a...
متن کاملApproximability of Dodgson's rule
It is known that Dodgson’s rule is computationally very demanding. Tideman (1987) suggested an approximation to it but did not investigate how often his approximation selects the Dodgson winner. We show that under the Impartial Culture assumption the probability that the Tideman winner is the Dodgson winner tend to 1. However we show that the convergence of this probability to 1 is slow. We sug...
متن کاملComparison of the Effects of Self-Determination Skills Training and Parent Management Training on Externalizing Behavior Problems of Students
This study was carried out to compare the effects of self-determination skills training and parent management training on the externalizing behavior problems of students. This quasi-experimental research had a pretest-posttest, control group design. To achieve research goals, 45 students with externalizing behavior problems who were identified through Child Behavior Checklist (CBCL) and via ran...
متن کامل