Dear all,<div><br></div><div>A mathematically more sound notation of the importance of the functions of the council members would be the following:</div><div>M1>M2=M3>M4=M5=M6=M7, where Mn is a member of the set of all council members.</div>
<div>instead of P>[VPa, VPb]>[Ma, Mb, Mc, Md].</div><div><br></div><div>The "unified method" is called Schulze generalized proportional ranking.</div><div>This method would repeatedly apply the fill the not yet elected (vacant) seats of councils, that are</div>
<div>elected by STV method (FVSSTV).</div><div>Schulze describes his method in chapter 7 of <a href="http://m-schulze.webhop.net/schulze2.pdf">http://m-schulze.webhop.net/schulze2.pdf</a></div><div><br><a href="http://m-schulze.webhop.net/schulze2.pdf"></a></div>
<div>Best regards</div><div>Peter Zborník</div><div><br></div><div><br></div><div><br><div class="gmail_quote">On Fri, May 7, 2010 at 10:11 PM, Raph Frank <span dir="ltr"><<a href="mailto:raphfrk@gmail.com">raphfrk@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div class="im">On Fri, May 7, 2010 at 4:27 PM, Peter Zbornik <<a href="mailto:pzbornik@gmail.com">pzbornik@gmail.com</a>> wrote:<br>
</div><div class="im">> The proportional ranking needed is not P>VPa>VPb>Ma>Mb>Mc>Md,<br>
> but P>[VPa, VPb]>[Ma, Mb, Mc, Md].<br>
> Let us call this required ranking for "boundary conditions".<br>
<br>
</div>Schulze's method can do that too.<br>
<br>
Step 1: Elect the Schulze single seat method winner as President<br>
Step 2: Elect a 3 person council using Schulze-STV, but the President<br>
must be a member<br>
Step 3: Elect a 7 person council using Schulze-STV, but the President<br>
+ VPs must be members.<br>
<br>
I think this is what you meant by your unified method?<br>
<br>
Schulze rankings is just Schulze-STV, except you elect councils that<br>
increase in size by one each iteration, and members elected in<br>
previous iterations must be members of subsequent councils.<br>
<div class="im"><br>
> Example (from an email by Schulze):<br>
> "40 ABC<br>
> 25 BAC<br>
> 35 CBA<br>
> The Schulze proportional ranking is BAC.<br>
> However, for two seats, Droop proportionality, requires that A and C are<br>
> elected."<br>
><br>
> The "unified" method for two seats without boundary conditions would select<br>
> BA (i.e.Schulze STV)<br>
<br>
</div>Schulze-STV meets the Droop criterion, so would elect A and C in a 2 seat race.<br>
<br>
Schulze-rankings elects B and then A as you say.<br>
<br>
There are 2 steps:<br>
<br>
*** Work out A's score vs C: ***<br>
<br>
We split the voters in 2 groups<br>
<br>
Voters who prefer B to A: 60<br>
Voters who prefer C to A: 35<br>
<br>
There are no options in which group each voter can be placed, as no<br>
voter is eligible for both groups.<br>
<br>
The smallest group has 35 voters so, A better than than C gets 35 votes<br>
<br>
*** Work out C's score vs A ***<br>
<br>
Again we split into 2 groups<br>
<br>
Voters who prefer only B to C: 0<br>
Voters who prefer only A to C: 0<br>
Voters who prefer both to C: 65<br>
<br>
Thus we split the third group into 2 parts, as they can be placed in<br>
either group.<br>
<br>
Voters who prefer B to C: 32.5<br>
Voters who prefer A to C: 32.5<br>
<br>
The smallest group has 32.5 voters so, C better than A gets 32.5 votes<br>
<br>
Thus the result is<br>
<br>
A gets 35 votes and C get 32.5 votes, so A wins the 2nd seat.<br>
<br>
Anyway, I think the rankings method can be generalised to allow groups<br>
of candidates to be elected at once, rather than electing them one at<br>
a time.<br>
</blockquote></div><br></div>