[EM] Preliminary Range PAV results

Jameson Quinn jameson.quinn at gmail.com
Tue Jun 8 16:10:48 PDT 2010


OK, I think there's a bug in this formula. Can you try
max(0,(R/M-D(rN/R))/N)? M is the maximum Range vote (1, 99, 100, whatever);
the minimum is 0.

2010/6/6 Kristofer Munsterhjelm <km-elmet at broadpark.no>

> Jameson Quinn wrote:
>
>> Can you add a range-STV method? This would reweight ballots for elected
>> candidate X by:
>>
>> max(0,(N-D(rN/R))/N)
>>
>> where N is num voters, D is droop quota, r is ballot's range score for X,
>> and R is electorate's range total for X. This should be simple to code, a
>> small variant on greedy PAV with a different reweighting formula.
>>
>> This is a more STV-like method, in that it elects candidates in order of
>> some pseudo-"strong to weak", not in a proportional order as does greedy
>> PAV.
>>
>
> If N = total number of voters, then (unless there's a bug somewhere) we
> get:
>
> PA_Linear_Range_STV                                 0.29813 0.00031
>
> If N = the number of voters voting according to the ballot being
> reweighted, then the result is:
>

You mean, the number of identical ballots? Or the number of ballots with
identical orderings? or what?


>
> PA_Linear_Range_STV                                 0.20928 0.01991
>
> As a comparison:
>
> PA_Maj[Cardinal-20]                                 0.31348 0
> PA_STV                                              0.11902 0.10007
> PA_DHwL(L-R_offense/1/(wv),_0.925)                  0.20924 0.02172
>
> The first is Range, and the second is ordinary STV. The third is the
> closest ranked ballot method at this level of proportionality.
>
> If you suspect a bug, I could give examples where "N = size of entire
> electorate" gives a disproportional result (according to my program). "N =
> number voting this way" seems more well behaved, but if you're interested, I
> could also give an example where it differs from STV and/or Birational.
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.electorama.com/pipermail/election-methods-electorama.com/attachments/20100608/2436edaf/attachment-0004.htm>


More information about the Election-Methods mailing list