[EM] Better Than Expectation Approval Voting

2011-12-23 Thread fsimmons
Mike's exposition of basic Approval and Range strategy as variations on the 
theme of Better Than Expectation strategy was very interesting and valuable, 
including the recommendation of introducintg Approval after score or grade 
voting, which are much more familiar to most people.

That was probably the most important part of his message, but I want to make a 
few more remarks about Approval strategy.

1.  When there are candidates between the two front runners and you are not 
sure where to draw the approval line, put it adjacent to the candidate with the 
greatest likelihood of winning.  In other words put your approval cutoff 
adjacent to the candidate most likely to win on the side of the candidate next 
most likely to win.  This is what Rob LeGrand calls strategy A.

2.  Suppose that order is easier than ratings for you.  Joe Weinstein's idea is 
to approve candidate X if and only if it is more likely that the winner will be 
someone that you rank behind candidate X than someone that you rank ahead of 
candidate X.  Note that when there are two obvious frontrunners Joe's strategy 
reduces to Rob's strategy A.

3.  Suppose that on principle someone would never use approval strategy on a 
score/grade/range ballot, but is forced to use an approval ballot anyway.  How 
could they vote as close as possible to their scruples?  For example suppose 
that you would give candidate X a score of 37 percent on a high resolution 
score ballot, but are forced to vote approval style.  In this case you can have 
a random number generator pick a number between zero and 100.  If the random 
number is less than 37, then approve the candidate, otherwise do not.  If all 
like minded voters used this same strategy, 37 percent of them would approve 
candidate X, and the result would be the same as if all of them had voted 37 on 
a scale from zero to one hundred.

Now for the interesting part:  if you use this strategy on your approval 
ballot, the expected number of candidates that you would approve is simply the 
sum of the probabilities of your approving the individual candiates, i.e. the 
total score of all the candidates on your score ballot divided by the maximum 
possible score (100 in the example).  Suppose that there are n candidates, and 
that the expected number that you will approve is k.  Then instead of going 
through the random number rigamarole, just approve your top k candidates.

Forest

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[EM] Better Than Expectation Approval Voting (2nd try readable format)

2011-12-23 Thread fsimmons
 
Mike's exposition of basic Approval and Range strategy as variations on the 
theme of Better Than 
Expectation strategy was very interesting and valuable, including the 
recommendation of introducintg 
Approval after score or grade voting, which are much more familiar to most 
people.
 
That was probably the most important part of his message, but I want to make a 
few more remarks about 
Approval strategy.
 
1.  When there are candidates between the two front runners and you are not 
sure where to draw the 
approval line, put it adjacent to the candidate with the greatest likelihood of 
winning.  In other words put your 
approval cutoff adjacent to the candidate most likely to win on the side of the 
candidate next most likely to 
win.  This is what Rob LeGrand calls strategy A.
 
2.  Suppose that order is easier than ratings for you.  Joe Weinstein's idea is 
to approve candidate X if and 
only if it is more likely that the winner will be someone that you rank behind 
candidate X than someone that 
you rank ahead of candidate X.  Note that when there are two obvious 
frontrunners Joe's strategy reduces to 
Rob's strategy A.
 
3.  Suppose that on principle someone would never use approval strategy on a 
score/grade/range ballot, but 
is forced to use an approval ballot anyway.  How could they vote as close as 
possible to their scruples?  
For example suppose that you would give candidate X a score of 37 percent on a 
high resolution score 
ballot, but are forced to vote approval style.  In this case you can have a 
random number generator pick a 
number between zero and 100.  If the random number is less than 37, then 
approve the candidate, 
otherwise do not.  If all like minded voters used this same strategy, 37 
percent of them would approve 
candidate X, and the result would be the same as if all of them had voted 37 on 
a scale from zero to one 
hundred.
 
Now for the interesting part:  if you use this strategy on your approval 
ballot, the expected number of 
candidates that you would approve is simply the sum of the probabilities of 
your approving the individual 
candiates, i.e. the total score of all the candidates on your score ballot 
divided by the maximum possible 
score (100 in the example).  Suppose that there are n candidates, and that the 
expected number that you 
will approve is k.  Then instead of going through the random number rigamarole, 
just approve your top k 
candidates.
 
Forest

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Re: [EM] Better Than Expectation Approval Voting (2nd try readable format)

2011-12-23 Thread Jobst Heitzig
Forest wrote:
 Now for the interesting part:  if you use this strategy on your approval 
 ballot, the expected number of 
 candidates that you would approve is simply the sum of the probabilities of 
 your approving the individual 
 candiates, i.e. the total score of all the candidates on your score ballot 
 divided by the maximum possible 
 score (100 in the example).  Suppose that there are n candidates, and that 
 the expected number that you 
 will approve is k.  Then instead of going through the random number 
 rigamarole, just approve your top k 
 candidates.

So we could justifiably call this strategy the honest approval
strategy, since if preferences are sufficiently mixed and all voters use
this strategy, the outcome is the same as the one with sincere Range
ballots, i.e., the option with the highest total rating!

Happy Holidays from Jobst to all of you!

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