<div dir="ltr">PSC is <a href="https://en.wikipedia.org/wiki/Proportionality_for_solid_coalitions">proportionality for solid coalitions</a>.</div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Jul 16, 2024 at 11:07 AM Richard, the VoteFair guy <<a href="mailto:electionmethods@votefair.org">electionmethods@votefair.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">On 7/15/2024 3:20 PM, Closed Limelike Curves wrote:<br>
 > Richard, I'd suggest taking a look at the newest<br>
 > version of Wikipedia's PSC article (and the<br>
 > citations in there); ...<br>
<br>
I don't recognize the PSC acronym.<br>
<br>
And I can't find it in Wikipedia's PSC list:<br>
<br>
<a href="https://en.wikipedia.org/wiki/PSC" rel="noreferrer" target="_blank">https://en.wikipedia.org/wiki/PSC</a><br>
<br>
Also, I suggest changing the email "subject" to the full name of <br>
whatever PSC is.<br>
<br>
Richard Fobes<br>
<br>
<br>
On 7/15/2024 3:20 PM, Closed Limelike Curves wrote:<br>
> Richard, I'd suggest taking a look at the newest version of Wikipedia's <br>
> PSC article (and the citations in there); nonpartisan PR algorithms <br>
> other than STV are a very new field of research, and we're just barely <br>
> starting to study what algorithms satisfy what proportionality axioms.<br>
> <br>
> STV does try to put together a coalition, but this involves a very basic <br>
> greedy search for cohesive/solid coalitions that support a single group <br>
> of candidates. e.g. say a Hispanic Republican's preferences are <br>
> something like "vote for a Hispanic Republican, then non-Hispanic <br>
> Republicans, then a Hispanic Democrat"; whereas others Hispanic <br>
> Republicans care more about ethnicity than about party. In this <br>
> situation, there's no solid coalition for Hispanics /or/ Republicans, so <br>
> it's very prone to underrepresent one of these groups. IIRC the EVC's <br>
> proposal for a proportional STAR algorithm works on basically the same <br>
> principle, as does anything that assigns seats sequentially/greedily, <br>
> which is why I tend to dislike them; whereas PAV is optimization-based, <br>
> so it tends to find better apportionments across cross-cutting <br>
> coalitions. I think Schulze STV also satisfies similar properties (but <br>
> only locally, because global optimization across committees requires <br>
> voters to give candidates ratings).<br>
> <br>
> On Sun, Jul 14, 2024 at 10:22 AM Richard, the VoteFair guy <br>
> <<a href="mailto:electionmethods@votefair.org" target="_blank">electionmethods@votefair.org</a> <mailto:<a href="mailto:electionmethods@votefair.org" target="_blank">electionmethods@votefair.org</a>>> wrote:<br>
> <br>
>     On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:<br>
>       > ...  my guess is the effect of STV is probably going to be limited<br>
>       > compared to other methods, because STV is only proportional for<br>
>     solid<br>
>       > coalitions, i.e. voting blocs moving in perfect lockstep with each<br>
>       > other, and only if they exceed a full quota. ...<br>
> <br>
>     When using STV, coalitions don't need to be "solid."<br>
> <br>
>     STV calculations automatically identify de-facto "coalitions."  Each<br>
>     candidate can be thought of as a de-facto coalition.<br>
> <br>
>     One way to think of this concept is that STV gives any coalition a<br>
>     "second try" when filling the second seat, and a "third try" when<br>
>     filling the third seat.<br>
> <br>
>     In contrast, IRV provides only "one try" for a coalition to elect their<br>
>     candidate.  So for IRV, a "solid" coalition voting with the same tactic<br>
>     does have an advantage compared to a loose (non-solid) coalition.<br>
> <br>
>     I'm not saying STV is better than PAV.  I'm saying this specific<br>
>     criticism of STV -- thinking that a coalition must be "solid" -- is not<br>
>     a valid reason to dismiss STV.<br>
> <br>
>     Richard Fobes<br>
> <br>
> <br>
> <br>
>     On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:<br>
>      > Ahh, yeah, any PR method will outperform winner-take-all on this<br>
>     metric.<br>
>      > If cities are using STV for their city councils, that might imply<br>
>      > single-winner IRV actively reduces minority representation.<br>
>      ><br>
>      > That said, my guess is the effect of STV is probably going to be<br>
>     limited<br>
>      > compared to other methods, because STV is only proportional for<br>
>     solid<br>
>      > coalitions, i.e. voting blocs moving in perfect lockstep with each<br>
>      > other, and only if they exceed a full quota. So, for example, if<br>
>     ethnic<br>
>      > minorities tend to vote for a mix of white and minority<br>
>     candidates, or<br>
>      > if they're split across party lines (e.g. Hispanics only go about<br>
>     60-40<br>
>      > for Democrats), this will tend to break up and dilute their<br>
>     interests.<br>
>      > It's not enough to have a quota of Hispanics who rate Hispanic<br>
>      > Republicans and Hispanic Democrats highly; you need to have a<br>
>     full quota<br>
>      > rank /either/ a Hispanic Republican or a Hispanic Democrat at the<br>
>     top of<br>
>      > their ballots. The effect is the same as center-squeeze, where<br>
>     your vote<br>
>      > gets "stuck" with a weak candidate who nevertheless has enough first<br>
>      > preferences to stay in the race for several rounds. By the time this<br>
>      > candidate is eliminated, the more-electable candidates with fewer<br>
>     first<br>
>      > preferences have been defeated.<br>
>      ><br>
>      > But from what I can tell, this is much trickier to resolve than<br>
>      > center-squeeze; proportional Condorcet methods don't seem to have<br>
>     any<br>
>      > guarantees on how out-of-whack a coalition can get, although I think<br>
>      > Schulze STV has a nice local stability property.<br>
>      ><br>
>      > Most ethnic minorities aren’t solid coalitions, although<br>
>      > African-Americans happen to be so overwhelmingly Democratic they<br>
>     might<br>
>      > act like one. Something like PAV that approximately satisfies the<br>
>     core<br>
>      > property should do better at giving minority voters more<br>
>     representation.<br>
>      ><br>
>      > On Thu, Jul 11, 2024 at 8:40 PM Richard, the VoteFair guy<br>
>      > <<a href="mailto:electionmethods@votefair.org" target="_blank">electionmethods@votefair.org</a><br>
>     <mailto:<a href="mailto:electionmethods@votefair.org" target="_blank">electionmethods@votefair.org</a>><br>
>     <mailto:<a href="mailto:electionmethods@votefair.org" target="_blank">electionmethods@votefair.org</a><br>
>     <mailto:<a href="mailto:electionmethods@votefair.org" target="_blank">electionmethods@votefair.org</a>>>> wrote:<br>
>      ><br>
>      >     On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:<br>
>      >       > ... given there's no theoretical basis to think IRV would<br>
>     affect<br>
>      >       > city council and mayoral seats differently. ...<br>
>      ><br>
>      >     In the new Portland elections, "ranked choice voting" for<br>
>     city-council<br>
>      >     seats is STV (the Single Transferable Vote) with three seats per<br>
>      >     district, whereas "ranked choice voting" for Portland mayor is<br>
>      >     single-winner IRV (instant-runoff voting).<br>
>      ><br>
>      >     Of course Portland's three-seats-per-district STV city-council<br>
>      >     elections<br>
>      >     are going to yield more gender and racial diversity compared to<br>
>      >     single-winner IRV for electing Portland's mayor.<br>
>      ><br>
>      >     Richard Fobes<br>
>      ><br>
>      ><br>
>      >     On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:<br>
>      >      > I'm going to go ahead and say I'm skeptical either of these<br>
>      >     results will<br>
>      >      > replicate, given there's no theoretical basis to think IRV<br>
>      >     would affect<br>
>      >      > city council and mayoral seats differently. My guess is<br>
>     both results<br>
>      >      > would disappear if you used a hierarchical/partial pooling<br>
>     model to<br>
>      >      > reduce the noise in the estimates.<br>
>      >      ><br>
>      >      > On Thu, Jul 11, 2024 at 10:45 AM Michael Garman<br>
>      >      > <<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a><br>
>     <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a>><br>
>      >     <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a><br>
>     <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a>>><br>
>      >     <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a><br>
>     <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a>><br>
>      >     <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a><br>
>     <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a>>>>><br>
>      >      > wrote:<br>
>      >      ><br>
>      >      >     And that’s bad! But it doesn’t negate the point I made. In<br>
>      >     council<br>
>      >      >     races it helps. And that’s good!<br>
>      >      >     On Thu, Jul 11, 2024 at 1:44 PM Closed Limelike Curves<br>
>      >      >     <<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a><br>
>     <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a>><br>
>      >     <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a><br>
>     <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a>>><br>
>      >      >     <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a><br>
>     <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a>><br>
>      >     <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a><br>
>     <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a>>>>> wrote:<br>
>      >      ><br>
>      >      >          > In mayoral elections, RCV seems to *decrease*<br>
>     gender and<br>
>      >      >         racial/ethnic diversity.<br>
>      >      >         Sounds substantial!<br>
>      >      ><br>
>      >      >         On Thu, Jul 11, 2024 at 10:28 AM Michael Garman<br>
>      >      >         <<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a><br>
>     <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a>><br>
>      >     <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a><br>
>     <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a>>><br>
>      >      >         <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a><br>
>     <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a>><br>
>      >     <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a><br>
>     <mailto:<a href="mailto:michael.garman@rankthevote.us" target="_blank">michael.garman@rankthevote.us</a>>>>> wrote:<br>
>      >      ><br>
>      >      >              > In city council elections, RCV has a small but<br>
>      >     positive<br>
>      >      >             effect on racial/ethnic diversity<br>
>      >      >             Sounds substantial!<br>
>      >      ><br>
>      >      >             On Thu, Jul 11, 2024 at 1:26 PM Closed<br>
>     Limelike Curves<br>
>      >      >             <<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a><br>
>     <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a>><br>
>      >     <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a><br>
>     <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a>>><br>
>      >      >             <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a><br>
>     <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a>><br>
>      >     <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a><br>
>     <mailto:<a href="mailto:closed.limelike.curves@gmail.com" target="_blank">closed.limelike.curves@gmail.com</a>>>>> wrote:<br>
>      >      ><br>
>      >      >                 Empirically, IRV adoption has no substantial<br>
>      >     effects on<br>
>      >      >                 diversity<br>
>      >      ><br>
>      >     <br>
>       <<a href="https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/" rel="noreferrer" target="_blank">https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/</a> <<a href="https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/" rel="noreferrer" target="_blank">https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/</a>> <<a href="https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/" rel="noreferrer" target="_blank">https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/</a> <<a href="https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/" rel="noreferrer" target="_blank">https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/</a>>>>. In theory, I'd expect a small decrease in representation for minorities, because people of color tend to have higher rates of spoiled ballots, so IRV should hit them the hardest.<br>
>      >      ><br>
>      >      >                 In general, the theoretical advantages of IRV<br>
>      >     over FPP<br>
>      >      >                 are outweighed by its practical costs (spoiled<br>
>      >     ballots,<br>
>      >      >                 lower trust in elections, cost, etc.).<br>
>      >      >                 ----<br>
>      >      >                 Election-Methods mailing list - see<br>
>      >      > <a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a> <<a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a>><br>
>     <<a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a> <<a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a>>><br>
>      >     <<a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a> <<a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a>><br>
>     <<a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a> <<a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a>>>><br>
>      >      >                 for list info<br>
>      >      ><br>
>      >     ----<br>
>      >     Election-Methods mailing list - see <a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a><br>
>     <<a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a>><br>
>      >     <<a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a> <<a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a>>> for<br>
>     list info<br>
>      ><br>
>     ----<br>
>     Election-Methods mailing list - see <a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a><br>
>     <<a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a>> for list info<br>
> <br>
----<br>
Election-Methods mailing list - see <a href="https://electorama.com/em" rel="noreferrer" target="_blank">https://electorama.com/em</a> for list info<br>
</blockquote></div>