<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif;font-size:13px"><div>From: Vidar Wahlberg <canidae@exent.net><br>To: "election-methods@lists.electorama.com" <election-methods@lists.electorama.com> <br>Sent: Friday, 7 November 2014, 16:09<br>Subject: Re: [EM] Preferential Party-List Proportional Representation (PPLPR)<br> </div><div><br>>Whether PPLPR should be considered a PR method is actually an<br>>interesting thought. I would say it is a PR method, because if it isn't,<br>>then I would find it hard to argue that the voting system used in Zürich<br>>(two votes per voter) could be considered a PR system as well. There<br>>they have a (very limited) oppertunity to score the parties. They can<br>>give both votes to one party, or they could give one vote to two<br>>different parties. PPLPR extends this feature (and
removes the direct<br>>harm done to your first preference).<br>>As far as I can tell, all voting systems that allows you to rank or give<br>>score to candidates/parties in a multiwinner election will encroach into<br>>opposing candidates/parties allocation, some more than others. If they<br>>didn't, then they would give the same result as a plurality based<br>>system. STV will not encroach as much as for example Approval or<br>>(reweighted) Range voting, but as a left supporter in a multiwinner STV<br>>election you could still cause a centrist candidate to win a seat over a<br>>right candidate by ranking the centrist candidate above the right<br>>candidate (instead of ranking them equally).</div><div style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif; font-size: 13px; font-style: normal; background-color: transparent;"><br></div><div style="color: rgb(0, 0,
0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif; font-size: 13px; font-style: normal; background-color: transparent;">So why is it that you've developed this particular borderline proportional method, when there are others out there that would be less borderline? In your previous example, you had:</div><div style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif; font-size: 13px; font-style: normal; background-color: transparent;"><br></div><div style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif; font-size: 13px; font-style: normal; background-color: transparent;">50%: L>C</div><div style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif; font-size: 13px; font-style: normal; background-color: transparent;">50%: R</div><div
style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif; font-size: 13px; font-style: normal; background-color: transparent;"><br></div><div style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif; font-size: 13px; font-style: normal; background-color: transparent;">Then the seat allocation would be:</div><div style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif; font-size: 13px; font-style: normal; background-color: transparent;"><br></div><div style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif; font-size: 13px; font-style: normal; background-color: transparent;">L; 50%</div><div style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif; font-size:
13px; font-style: normal; background-color: transparent;">C: 12.5%</div><div style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif; font-size: 13px; font-style: normal; background-color: transparent;">R: 37.5%</div><div style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif; font-size: 13px; font-style: normal; background-color: transparent;"><br></div><div style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif; font-size: 13px; font-style: normal; background-color: transparent;">The second preference of C causes too much of an encroachment into the R allocation. All STV methods would give R 50% of the seats and I would say your method gives disproportional results. What advantages would you say your method has?</div></div></body></html>