[EM] Approval vs. IRV

[Dave Ketchum]

On Mon, 18 Oct 2004 19:32:22 -0400 James Green-Armytage wrote:

> 
>>That's why we want an election method that can find 
>>the compromise choice that serves 60% of the people when we might 
>>otherwise get some faction's 40% or 41% choice.
>>
> 
> 	Of course, majoritarian methods like Condorcet can't guarantee 60%, or
> anything over 50.00001%. But anyway, I agree with you that the
> probabilistic "timeshare" approach is not a good one for serious public
> offices (mayor, president, etc.) or decisions.
> 

Actually, you cannot guarantee to please any particular percentage of the 
voters.

Condorcet is an attempt to do the best that can be done with 
whatever ballots get cast.

IRV talks loudly of a majority, but they are happy with a majority of 
whatever ballots are left after discarding some of those that do not help 
make a majority.

Try for size an election in which truncation is permitted (should be 
permitted to avoid demanding that voters vote beyond their understanding 
of the candidates), and that the issues cause each voter to reject most 
candidates:

30 A
29 B,D
27 C
13 D
1 E

We can get here with strong disagreements on two issues such as abortion.

IRV will discard C, D, and E, and declare A winner with a majority (just 
over half) of the remaining 59%.

Condorcet will see that B, C, and E are least liked, and declare D winner 
with 42% of total votes.
-- 
  davek at clarityconnect.com    people.clarityconnect.com/webpages3/davek
  Dave Ketchum   108 Halstead Ave, Owego, NY  13827-1708   607-687-5026
            Do to no one what you would not want done to you.
                  If you want peace, work for justice.