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Dgamble997@aol.com a écrit :
<blockquote TYPE=CITE><font face="Arial"><font size=-1>I wrote:</font></font>
<p><font face="Arial"><font size=-1>>>What I'm interested in at the moment
is going beyond IRV, Condorcet and</font></font>
<br><font face="Arial"><font size=-1>>>Approval towards a single winner
system that gives high utility,</font></font>
<br><font face="Arial"><font size=-1>>>generally preferred winners.</font></font>
<p><font face="Arial"><font size=-1>James Armytage-Green replied:</font></font>
<p><font face="Arial"><font size=-1>>Sounds interesting. What do you have
in mind specifically?</font></font>
<br>
<p><b><u><font face="Arial"><font size=-1>Ranked Approval</font></font></u></b>
<p><u><font face="Arial"><font size=-1>How you vote</font></font></u>
<p><font face="Arial"><font size=-1>Voters may approve as few or as many
candidates as they wish.</font></font>
<p><font face="Arial"><font size=-1>Voters then rank the candidates they
have approved (equal ranking allowed). You can only rank candidates who
you approve.</font></font></blockquote>
I like that. This is the same input I use for SPPA to produce a proportional
multiple-winners result...
<blockquote TYPE=CITE><u><font face="Arial"><font size=-1>How you decide
the winner:</font></font></u>
<p><font face="Arial"><font size=-1>If no candidate is approved on a majority
of ballots the most approved candidate wins.</font></font>
<p><font face="Arial"><font size=-1>If one candidate is approved on a majority
of ballots then that candidate wins.</font></font>
<p><font face="Arial"><font size=-1>If two or more candidates are approved
by a majority of voters pairwise comparisons are conducted between these
candidates to determine the winner. In the case of a Condorcet cycle the
most approved candidate wins.</font></font>
<p><u><font face="Arial"><font size=-1>Several examples</font></font></u>
<p><u><font face="Arial"><font size=-1>Example 1</font></font></u>
<p><font face="Arial"><font size=-1>45 A 100> B 70 > C 0</font></font>
<br><font face="Arial"><font size=-1>10 B 100> A 70 > C 0</font></font>
<br><font face="Arial"><font size=-1>5 B 100> C 70 > A 0</font></font>
<br><font face="Arial"><font size=-1>40 C 100> B 70 > A 0</font></font>
<p><font face="Arial"><font size=-1>Translates using zero-info approval
strategy to:</font></font>
<p><font face="Arial"><font size=-1>45 A>B</font></font>
<br><font face="Arial"><font size=-1>10 B>A</font></font>
<br><font face="Arial"><font size=-1>5 B>C</font></font>
<br><font face="Arial"><font size=-1>40 C>B</font></font>
<p><font face="Arial"><font size=-1>Approval scores:</font></font>
<p><font face="Arial"><font size=-1>A 55</font></font>
<br><font face="Arial"><font size=-1>B 100</font></font>
<br><font face="Arial"><font size=-1>C 45</font></font>
<p><font face="Arial"><font size=-1>A pairwise comparison is conducted
between A and B:</font></font>
<p><font face="Arial"><font size=-1>A v B 45 v 55</font></font>
<p><font face="Arial"><font size=-1>B wins.</font></font>
<p><u><font face="Arial"><font size=-1>Example 2</font></font></u>
<p><font face="Arial"><font size=-1>45 A 100> B 10 > C 0</font></font>
<br><font face="Arial"><font size=-1>10 B 100> A 90 > C 0</font></font>
<br><font face="Arial"><font size=-1>5 B 100> C 90 > A 0</font></font>
<br><font face="Arial"><font size=-1>40 C 100> B 10 > A 0</font></font>
<p><font face="Arial"><font size=-1>Translates using zero info approval
strategy into:</font></font>
<p><font face="Arial"><font size=-1>45 A</font></font>
<br><font face="Arial"><font size=-1>10 B>A</font></font>
<br><font face="Arial"><font size=-1>5 B>C</font></font>
<br><font face="Arial"><font size=-1>40 C</font></font>
<p><font face="Arial"><font size=-1>Approval scores:</font></font>
<p><font face="Arial"><font size=-1>A 55</font></font>
<br><font face="Arial"><font size=-1>B 15</font></font>
<br><font face="Arial"><font size=-1>C 45</font></font>
<p><font face="Arial"><font size=-1>A is the only candidate approved by
a majority and therefore A wins.</font></font>
<p><u><font face="Arial"><font size=-1>Example 3</font></font></u>
<p><font face="Arial"><font size=-1>55 A 100> B 70> C 0</font></font>
<br><font face="Arial"><font size=-1>10 B 100> A 70 > C 0</font></font>
<br><font face="Arial"><font size=-1>35 C100 > B70 > A 0</font></font>
<p><font face="Arial"><font size=-1>Translates using zero-info approval
strategy to:</font></font>
<p><font face="Arial"><font size=-1>55 A>B</font></font>
<br><font face="Arial"><font size=-1>10 B>A</font></font>
<br><font face="Arial"><font size=-1>35 C>B</font></font>
<p><font face="Arial"><font size=-1>Approval scores:</font></font>
<p><font face="Arial"><font size=-1>A 65</font></font>
<br><font face="Arial"><font size=-1>B 100</font></font>
<br><font face="Arial"><font size=-1>C 35</font></font>
<p><font face="Arial"><font size=-1>A pairwise comparison is conducted
between A and B:</font></font>
<p><font face="Arial"><font size=-1>A v B 55 v 45</font></font>
<p><font face="Arial"><font size=-1>A wins.</font></font>
<p><u><font face="Arial"><font size=-1>Example 4</font></font></u>
<p><font face="Arial"><font size=-1>26: Bush 100 > Dean 10 > Kerry 0</font></font>
<br><font face="Arial"><font size=-1>22: Bush 100 > Kerry 10 > Dean 0</font></font>
<br><font face="Arial"><font size=-1>26: Dean 100 > Kerry 90 > Bush 0</font></font>
<br><font face="Arial"><font size=-1>1: Dean 100 > Bush 50 > Kerry 0</font></font>
<br><font face="Arial"><font size=-1>21: Kerry 100 > Dean 90 > Bush 0</font></font>
<br><font face="Arial"><font size=-1>4: Kerry 100 > Bush 50 > Dean 0</font></font>
<p><font face="Arial"><font size=-1>In this example the mean rating for
the Dean>Bush>Kerry voter and the Kerry>Bush>Dean voters is 50 which is
Bush's rating so I'll work the method with Bush approved by these voters
and Bush not approved.</font></font>
<p><font face="Arial"><font size=-1>Bush not approved translates into the
ballots:</font></font>
<p><font face="Arial"><font size=-1>26: Bush</font></font>
<br><font face="Arial"><font size=-1>22: Bush</font></font>
<br><font face="Arial"><font size=-1>26: Dean > Kerry</font></font>
<br><font face="Arial"><font size=-1>1: Dean</font></font>
<br><font face="Arial"><font size=-1>21: Kerry> Dean</font></font>
<br><font face="Arial"><font size=-1>4: Kerry</font></font>
<p><font face="Arial"><font size=-1>Approval scores:</font></font>
<p><font face="Arial"><font size=-1>Bush 48</font></font>
<br><font face="Arial"><font size=-1>Dean 48</font></font>
<br><font face="Arial"><font size=-1>Kerry 51</font></font>
<p><font face="Arial"><font size=-1>Kerry is the only candidate approved
by a majority of voters therefore Kerry wins.</font></font>
<p><font face="Arial"><font size=-1>With Bush approved translates into
the ballots:</font></font>
<p><font face="Arial"><font size=-1>26: Bush</font></font>
<br><font face="Arial"><font size=-1>22: Bush</font></font>
<br><font face="Arial"><font size=-1>26: Dean > Kerry</font></font>
<br><font face="Arial"><font size=-1>1: Dean > Bush</font></font>
<br><font face="Arial"><font size=-1>21: Kerry> Dean</font></font>
<br><font face="Arial"><font size=-1>4: Kerry > Bush</font></font>
<br>
<p><font face="Arial"><font size=-1>Approval scores:</font></font>
<p><font face="Arial"><font size=-1>Bush 53</font></font>
<br><font face="Arial"><font size=-1>Dean 48</font></font>
<br><font face="Arial"><font size=-1>Kerry 51</font></font>
<p><font face="Arial"><font size=-1>Pairwise comparison between Bush and
Kerry.</font></font>
<p><font face="Arial"><font size=-1>Kerry versus Bush
51 v 49</font></font>
<p><font face="Arial"><font size=-1>Kerry wins.</font></font>
<p><font face="Arial"><font size=-1>The idea is that when voters cast sincere
ballots the method will elect a high utility generally preferred winner
if there is one. I have only partially explored voting strategies as regards
this method.</font></font>
<p><font face="Arial"><font size=-1>One final point I am fairly certain
on is that a very similar or identical method has been proposed on this
list by somebody else ( possibly Kevin Venzke ) but I'm sure who or when.</font></font></blockquote>
I do not think it is equivalent to IRV or Condocet methods with residual
approval weights (methods I presented some time ago),
<br>but I will look at your method....
<blockquote TYPE=CITE><font face="Arial"><font size=-1></font></font>
<p><font face="Arial"><font size=-1>Comments, criticisms ?</font></font>
<p><font face="Arial"><font size=-1>David Gamble</font></font></blockquote>
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