[EM] Voting Systems Study of the League of Women Voters of Minnesota

James Green-Armytage jarmyta at antioch-college.edu
Sun Oct 10 20:33:31 PDT 2004


>> Condorcet Voting System (Voters rank candidates; winner
>> is the one who can top each of others in a series of
>> head-to-head contests)
>> * Allows voters to express preferences among candidates
>> * Considered by some mathematicians to best identify
>>   winner in three-way race
>> * May result in a tie that requires pre-election decision
>>   on how to break tie

	I really wish that people wouldn't refer to a majority rule cycle as a
"tie". It's very misleading. And the way they use it here is especially
so. They regard Condorcet as a single method with a resolvability problem
rather than a family of voting methods (e.g. beatpath, ranked pairs, etc.)
which is much more accurate. 

>> * Is vulnerable to manipulation

	As you know, I think that there is some validity to this.

>> * May be difficult for voters to understand
>>
>> Instant Runoff Voting System (Voters rank candidates;
>> votes for candidate with fewest firstchoice votes are
>> redistributed according to their second choices until
>> one candidate achieves a majority)
>> * Ensures majority rule

	Only according to a definition of majority rule which I consider to be
inadequate.

>> * Allows voters to express preferences among candidates
>> * Eliminates problems of spoiler candidates knocking off
>>   major candidates
>> * Eliminates need for run-off elections
>> * Does not meet mathematical requirement for monotonicity
>
>In short: IRV violates monotonicity, but it ensures majority
>rule and eliminates the need for run-off elections and it is
>spoiler-proof and immune to manipulation.

	2 out of 5 are correct... not so good.
>
>
>Furthermore, in appendix 3 they argue that Condorcet requires
>a change of the constitution while IRV doesn't.
>
	Somehow I doubt that there is anything about the "later-no-harm"
criterion in any federal or state constitution. I think that this part of
Brown v. Smallwood reflects little else besides the personal opinions of a
few judges.

James




More information about the Election-Methods mailing list