Double Defeat Hare
On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:
... my guess is the effect of STV is probably going to be limited
compared to other methods, because STV is only proportional for solid
coalitions, i.e. voting blocs moving in perfect lockstep with each
other, and only if they exceed a full quota. ...
When using STV, coalitions don't need to be "solid."
STV calculations automatically identify de-facto "coalitions." Each
candidate can be thought of as a de-facto coalition.
One way to think of this concept is that STV gives any coalition a
"second try" when filling the second seat, and a "third try" when
filling the third seat.
In contrast, IRV provides only "one try" for a coalition to elect their
candidate. So for IRV, a "solid" coalition voting with the same tactic
does have an advantage compared to a loose (non-solid) coalition.
I'm not saying STV is better than PAV. I'm saying this specific
criticism of STV -- thinking that a coalition must be "solid" -- is not
a valid reason to dismiss STV.
Richard Fobes
On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:
Ahh, yeah, any PR method will outperform winner-take-all on this metric.
If cities are using STV for their city councils, that might imply
single-winner IRV actively reduces minority representation.
That said, my guess is the effect of STV is probably going to be limited
compared to other methods, because STV is only proportional for solid
coalitions, i.e. voting blocs moving in perfect lockstep with each
other, and only if they exceed a full quota. So, for example, if ethnic
minorities tend to vote for a mix of white and minority candidates, or
if they're split across party lines (e.g. Hispanics only go about 60-40
for Democrats), this will tend to break up and dilute their interests.
It's not enough to have a quota of Hispanics who rate Hispanic
Republicans and Hispanic Democrats highly; you need to have a full quota
rank /either/ a Hispanic Republican or a Hispanic Democrat at the top of
their ballots. The effect is the same as center-squeeze, where your vote
gets "stuck" with a weak candidate who nevertheless has enough first
preferences to stay in the race for several rounds. By the time this
candidate is eliminated, the more-electable candidates with fewer first
preferences have been defeated.
But from what I can tell, this is much trickier to resolve than
center-squeeze; proportional Condorcet methods don't seem to have any
guarantees on how out-of-whack a coalition can get, although I think
Schulze STV has a nice local stability property.
Most ethnic minorities aren’t solid coalitions, although
African-Americans happen to be so overwhelmingly Democratic they might
act like one. Something like PAV that approximately satisfies the core
property should do better at giving minority voters more representation.
On Thu, Jul 11, 2024 at 8:40 PM Richard, the VoteFair guy
<electionmethods@votefair.org mailto:electionmethods@votefair.org> wrote:
On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:
> ... given there's no theoretical basis to think IRV would affect
> city council and mayoral seats differently. ...
In the new Portland elections, "ranked choice voting" for city-council
seats is STV (the Single Transferable Vote) with three seats per
district, whereas "ranked choice voting" for Portland mayor is
single-winner IRV (instant-runoff voting).
Of course Portland's three-seats-per-district STV city-council
elections
are going to yield more gender and racial diversity compared to
single-winner IRV for electing Portland's mayor.
Richard Fobes
On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:
I'm going to go ahead and say I'm skeptical either of these
results will
replicate, given there's no theoretical basis to think IRV
would affect
city council and mayoral seats differently. My guess is both results
would disappear if you used a hierarchical/partial pooling model to
reduce the noise in the estimates.
On Thu, Jul 11, 2024 at 10:45 AM Michael Garman
<michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>>>
wrote:
And that’s bad! But it doesn’t negate the point I made. In
council
races it helps. And that’s good!
On Thu, Jul 11, 2024 at 1:44 PM Closed Limelike Curves
<closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>>> wrote:
> In mayoral elections, RCV seems to decrease gender and
racial/ethnic diversity.
Sounds substantial!
On Thu, Jul 11, 2024 at 10:28 AM Michael Garman
<michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>>> wrote:
> In city council elections, RCV has a small but
positive
effect on racial/ethnic diversity
Sounds substantial!
On Thu, Jul 11, 2024 at 1:26 PM Closed Limelike Curves
<closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>>> wrote:
Empirically, IRV adoption has no substantial
effects on
diversity
<https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/ <https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/>>. 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.
In general, the theoretical advantages of IRV
over FPP
are outweighed by its practical costs (spoiled
ballots,
lower trust in elections, cost, etc.).
----
Election-Methods mailing list - see
https://electorama.com/em https://electorama.com/em
<https://electorama.com/em <https://electorama.com/em>>
for list info
----
Election-Methods mailing list - see https://electorama.com/em
<https://electorama.com/em> for list info
Richard, I'd suggest taking a look at the newest version of Wikipedia's PSC
article (and the citations in there); nonpartisan PR algorithms other than
STV are a very new field of research, and we're just barely starting to
study what algorithms satisfy what proportionality axioms.
STV does try to put together a coalition, but this involves a very basic
greedy search for cohesive/solid coalitions that support a single group of
candidates. e.g. say a Hispanic Republican's preferences are something like
"vote for a Hispanic Republican, then non-Hispanic Republicans, then a
Hispanic Democrat"; whereas others Hispanic Republicans care more about
ethnicity than about party. In this situation, there's no solid coalition
for Hispanics or Republicans, so it's very prone to underrepresent one of
these groups. IIRC the EVC's proposal for a proportional STAR algorithm
works on basically the same principle, as does anything that assigns seats
sequentially/greedily, which is why I tend to dislike them; whereas PAV is
optimization-based, so it tends to find better apportionments across
cross-cutting coalitions. I think Schulze STV also satisfies similar
properties (but only locally, because global optimization across committees
requires voters to give candidates ratings).
On Sun, Jul 14, 2024 at 10:22 AM Richard, the VoteFair guy <
electionmethods@votefair.org> wrote:
On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:
... my guess is the effect of STV is probably going to be limited
compared to other methods, because STV is only proportional for solid
coalitions, i.e. voting blocs moving in perfect lockstep with each
other, and only if they exceed a full quota. ...
When using STV, coalitions don't need to be "solid."
STV calculations automatically identify de-facto "coalitions." Each
candidate can be thought of as a de-facto coalition.
One way to think of this concept is that STV gives any coalition a
"second try" when filling the second seat, and a "third try" when
filling the third seat.
In contrast, IRV provides only "one try" for a coalition to elect their
candidate. So for IRV, a "solid" coalition voting with the same tactic
does have an advantage compared to a loose (non-solid) coalition.
I'm not saying STV is better than PAV. I'm saying this specific
criticism of STV -- thinking that a coalition must be "solid" -- is not
a valid reason to dismiss STV.
Richard Fobes
On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:
Ahh, yeah, any PR method will outperform winner-take-all on this metric.
If cities are using STV for their city councils, that might imply
single-winner IRV actively reduces minority representation.
That said, my guess is the effect of STV is probably going to be limited
compared to other methods, because STV is only proportional for solid
coalitions, i.e. voting blocs moving in perfect lockstep with each
other, and only if they exceed a full quota. So, for example, if ethnic
minorities tend to vote for a mix of white and minority candidates, or
if they're split across party lines (e.g. Hispanics only go about 60-40
for Democrats), this will tend to break up and dilute their interests.
It's not enough to have a quota of Hispanics who rate Hispanic
Republicans and Hispanic Democrats highly; you need to have a full quota
rank /either/ a Hispanic Republican or a Hispanic Democrat at the top of
their ballots. The effect is the same as center-squeeze, where your vote
gets "stuck" with a weak candidate who nevertheless has enough first
preferences to stay in the race for several rounds. By the time this
candidate is eliminated, the more-electable candidates with fewer first
preferences have been defeated.
But from what I can tell, this is much trickier to resolve than
center-squeeze; proportional Condorcet methods don't seem to have any
guarantees on how out-of-whack a coalition can get, although I think
Schulze STV has a nice local stability property.
Most ethnic minorities aren’t solid coalitions, although
African-Americans happen to be so overwhelmingly Democratic they might
act like one. Something like PAV that approximately satisfies the core
property should do better at giving minority voters more representation.
On Thu, Jul 11, 2024 at 8:40 PM Richard, the VoteFair guy
<electionmethods@votefair.org mailto:electionmethods@votefair.org>
wrote:
On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:
... given there's no theoretical basis to think IRV would affect
city council and mayoral seats differently. ...
In the new Portland elections, "ranked choice voting" for
city-council
seats is STV (the Single Transferable Vote) with three seats per
district, whereas "ranked choice voting" for Portland mayor is
single-winner IRV (instant-runoff voting).
Of course Portland's three-seats-per-district STV city-council
elections
are going to yield more gender and racial diversity compared to
single-winner IRV for electing Portland's mayor.
Richard Fobes
On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:
I'm going to go ahead and say I'm skeptical either of these
results will
replicate, given there's no theoretical basis to think IRV
would affect
city council and mayoral seats differently. My guess is both
results
would disappear if you used a hierarchical/partial pooling model
to
reduce the noise in the estimates.
On Thu, Jul 11, 2024 at 10:45 AM Michael Garman
<michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>>>
wrote:
And that’s bad! But it doesn’t negate the point I made. In
council
races it helps. And that’s good!
On Thu, Jul 11, 2024 at 1:44 PM Closed Limelike Curves
<closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>>> wrote:
In mayoral elections, RCV seems to decrease gender
and
racial/ethnic diversity.
Sounds substantial!
On Thu, Jul 11, 2024 at 10:28 AM Michael Garman
<michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>>> wrote:
In city council elections, RCV has a small but
positive
effect on racial/ethnic diversity
Sounds substantial!
On Thu, Jul 11, 2024 at 1:26 PM Closed Limelike Curves
<closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>>> wrote:
Empirically, IRV adoption has no substantial
effects on
diversity
<
https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/
<
https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/>>.
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.
In general, the theoretical advantages of IRV
over FPP
are outweighed by its practical costs (spoiled
ballots,
lower trust in elections, cost, etc.).
----
Election-Methods mailing list - see
<https://electorama.com/em <https://electorama.com/em>>
for list info
----
Election-Methods mailing list - see https://electorama.com/em
<https://electorama.com/em> for list info
Election-Methods mailing list - see https://electorama.com/em for list
info
So it seems that this is because PAV is an elect-all-at-once method rather than sequential, as opposed to there being something special about PAV per se. Of course it might be computationally too expensive to run PAV optimally in a given election anyway. There is also Phragmen, which is more proportional than PAV anyway, I would say. PAV fails what I would consider to be the basic PR criterion for an approval method - passing perfect representation when the number of elected candidates is the same as the number of voters. Phragmen doesn't have as good monotonic properties as PAV though. It passes, but in a weaker sense.
Toby
On Monday 15 July 2024 at 23:20:51 BST, Closed Limelike Curves closed.limelike.curves@gmail.com wrote:
Richard, I'd suggest taking a look at the newest version of Wikipedia's PSC article (and the citations in there); nonpartisan PR algorithms other than STV are a very new field of research, and we're just barely starting to study what algorithms satisfy what proportionality axioms.
STV does try to put together a coalition, but this involves a very basic greedy search for cohesive/solid coalitions that support a single group of candidates. e.g. say a Hispanic Republican's preferences are something like "vote for a Hispanic Republican, then non-Hispanic Republicans, then a Hispanic Democrat"; whereas others Hispanic Republicans care more about ethnicity than about party. In this situation, there's no solid coalition for Hispanics or Republicans, so it's very prone to underrepresent one of these groups. IIRC the EVC's proposal for a proportional STAR algorithm works on basically the same principle, as does anything that assigns seats sequentially/greedily, which is why I tend to dislike them; whereas PAV is optimization-based, so it tends to find better apportionments across cross-cutting coalitions. I think Schulze STV also satisfies similar properties (but only locally, because global optimization across committees requires voters to give candidates ratings).
On Sun, Jul 14, 2024 at 10:22 AM Richard, the VoteFair guy electionmethods@votefair.org wrote:
On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:
> ... my guess is the effect of STV is probably going to be limited
> compared to other methods, because STV is only proportional for solid
> coalitions, i.e. voting blocs moving in perfect lockstep with each
> other, and only if they exceed a full quota. ...
When using STV, coalitions don't need to be "solid."
STV calculations automatically identify de-facto "coalitions." Each
candidate can be thought of as a de-facto coalition.
One way to think of this concept is that STV gives any coalition a
"second try" when filling the second seat, and a "third try" when
filling the third seat.
In contrast, IRV provides only "one try" for a coalition to elect their
candidate. So for IRV, a "solid" coalition voting with the same tactic
does have an advantage compared to a loose (non-solid) coalition.
I'm not saying STV is better than PAV. I'm saying this specific
criticism of STV -- thinking that a coalition must be "solid" -- is not
a valid reason to dismiss STV.
Richard Fobes
On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:
Ahh, yeah, any PR method will outperform winner-take-all on this metric.
If cities are using STV for their city councils, that might imply
single-winner IRV actively reduces minority representation.
That said, my guess is the effect of STV is probably going to be limited
compared to other methods, because STV is only proportional for solid
coalitions, i.e. voting blocs moving in perfect lockstep with each
other, and only if they exceed a full quota. So, for example, if ethnic
minorities tend to vote for a mix of white and minority candidates, or
if they're split across party lines (e.g. Hispanics only go about 60-40
for Democrats), this will tend to break up and dilute their interests.
It's not enough to have a quota of Hispanics who rate Hispanic
Republicans and Hispanic Democrats highly; you need to have a full quota
rank /either/ a Hispanic Republican or a Hispanic Democrat at the top of
their ballots. The effect is the same as center-squeeze, where your vote
gets "stuck" with a weak candidate who nevertheless has enough first
preferences to stay in the race for several rounds. By the time this
candidate is eliminated, the more-electable candidates with fewer first
preferences have been defeated.
But from what I can tell, this is much trickier to resolve than
center-squeeze; proportional Condorcet methods don't seem to have any
guarantees on how out-of-whack a coalition can get, although I think
Schulze STV has a nice local stability property.
Most ethnic minorities aren’t solid coalitions, although
African-Americans happen to be so overwhelmingly Democratic they might
act like one. Something like PAV that approximately satisfies the core
property should do better at giving minority voters more representation.
On Thu, Jul 11, 2024 at 8:40 PM Richard, the VoteFair guy
<electionmethods@votefair.org mailto:electionmethods@votefair.org> wrote:
On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:
> ... given there's no theoretical basis to think IRV would affect
> city council and mayoral seats differently. ...
In the new Portland elections, "ranked choice voting" for city-council
seats is STV (the Single Transferable Vote) with three seats per
district, whereas "ranked choice voting" for Portland mayor is
single-winner IRV (instant-runoff voting).
Of course Portland's three-seats-per-district STV city-council
elections
are going to yield more gender and racial diversity compared to
single-winner IRV for electing Portland's mayor.
Richard Fobes
On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:
> I'm going to go ahead and say I'm skeptical either of these
results will
> replicate, given there's no theoretical basis to think IRV
would affect
> city council and mayoral seats differently. My guess is both results
> would disappear if you used a hierarchical/partial pooling model to
> reduce the noise in the estimates.
>
> On Thu, Jul 11, 2024 at 10:45 AM Michael Garman
> <michael.garman@rankthevote.us
mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us
mailto:michael.garman@rankthevote.us>>
> wrote:
>
> And that’s bad! But it doesn’t negate the point I made. In
council
> races it helps. And that’s good!
> On Thu, Jul 11, 2024 at 1:44 PM Closed Limelike Curves
> <closed.limelike.curves@gmail.com
mailto:closed.limelike.curves@gmail.com
> <mailto:closed.limelike.curves@gmail.com
mailto:closed.limelike.curves@gmail.com>> wrote:
>
> > In mayoral elections, RCV seems to decrease gender and
> racial/ethnic diversity.
> Sounds substantial!
>
> On Thu, Jul 11, 2024 at 10:28 AM Michael Garman
> <michael.garman@rankthevote.us
mailto:michael.garman@rankthevote.us
> <mailto:michael.garman@rankthevote.us
mailto:michael.garman@rankthevote.us>> wrote:
>
> > In city council elections, RCV has a small but
positive
> effect on racial/ethnic diversity
> Sounds substantial!
>
> On Thu, Jul 11, 2024 at 1:26 PM Closed Limelike Curves
> <closed.limelike.curves@gmail.com
mailto:closed.limelike.curves@gmail.com
> <mailto:closed.limelike.curves@gmail.com
mailto:closed.limelike.curves@gmail.com>> wrote:
>
> Empirically, IRV adoption has no substantial
effects on
> diversity
>
<https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/ https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/>. 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.
>
> In general, the theoretical advantages of IRV
over FPP
> are outweighed by its practical costs (spoiled
ballots,
> lower trust in elections, cost, etc.).
> ----
> Election-Methods mailing list - see
> https://electorama.com/em https://electorama.com/em
<https://electorama.com/em https://electorama.com/em>
> for list info
>
----
Election-Methods mailing list - see https://electorama.com/em
https://electorama.com/em for list info
Election-Methods mailing list - see https://electorama.com/em for list info
Election-Methods mailing list - see https://electorama.com/em for list info
On 7/15/2024 3:20 PM, Closed Limelike Curves wrote:
Richard, I'd suggest taking a look at the newest
version of Wikipedia's PSC article (and the
citations in there); ...
I don't recognize the PSC acronym.
And I can't find it in Wikipedia's PSC list:
https://en.wikipedia.org/wiki/PSC
Also, I suggest changing the email "subject" to the full name of
whatever PSC is.
Richard Fobes
On 7/15/2024 3:20 PM, Closed Limelike Curves wrote:
Richard, I'd suggest taking a look at the newest version of Wikipedia's
PSC article (and the citations in there); nonpartisan PR algorithms
other than STV are a very new field of research, and we're just barely
starting to study what algorithms satisfy what proportionality axioms.
STV does try to put together a coalition, but this involves a very basic
greedy search for cohesive/solid coalitions that support a single group
of candidates. e.g. say a Hispanic Republican's preferences are
something like "vote for a Hispanic Republican, then non-Hispanic
Republicans, then a Hispanic Democrat"; whereas others Hispanic
Republicans care more about ethnicity than about party. In this
situation, there's no solid coalition for Hispanics /or/ Republicans, so
it's very prone to underrepresent one of these groups. IIRC the EVC's
proposal for a proportional STAR algorithm works on basically the same
principle, as does anything that assigns seats sequentially/greedily,
which is why I tend to dislike them; whereas PAV is optimization-based,
so it tends to find better apportionments across cross-cutting
coalitions. I think Schulze STV also satisfies similar properties (but
only locally, because global optimization across committees requires
voters to give candidates ratings).
On Sun, Jul 14, 2024 at 10:22 AM Richard, the VoteFair guy
<electionmethods@votefair.org mailto:electionmethods@votefair.org> wrote:
On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:
> ... my guess is the effect of STV is probably going to be limited
> compared to other methods, because STV is only proportional for
solid
> coalitions, i.e. voting blocs moving in perfect lockstep with each
> other, and only if they exceed a full quota. ...
When using STV, coalitions don't need to be "solid."
STV calculations automatically identify de-facto "coalitions." Each
candidate can be thought of as a de-facto coalition.
One way to think of this concept is that STV gives any coalition a
"second try" when filling the second seat, and a "third try" when
filling the third seat.
In contrast, IRV provides only "one try" for a coalition to elect their
candidate. So for IRV, a "solid" coalition voting with the same tactic
does have an advantage compared to a loose (non-solid) coalition.
I'm not saying STV is better than PAV. I'm saying this specific
criticism of STV -- thinking that a coalition must be "solid" -- is not
a valid reason to dismiss STV.
Richard Fobes
On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:
Ahh, yeah, any PR method will outperform winner-take-all on this
metric.
If cities are using STV for their city councils, that might imply
single-winner IRV actively reduces minority representation.
That said, my guess is the effect of STV is probably going to be
limited
compared to other methods, because STV is only proportional for
solid
coalitions, i.e. voting blocs moving in perfect lockstep with each
other, and only if they exceed a full quota. So, for example, if
ethnic
minorities tend to vote for a mix of white and minority
candidates, or
if they're split across party lines (e.g. Hispanics only go about
60-40
for Democrats), this will tend to break up and dilute their
interests.
It's not enough to have a quota of Hispanics who rate Hispanic
Republicans and Hispanic Democrats highly; you need to have a
full quota
rank /either/ a Hispanic Republican or a Hispanic Democrat at the
top of
their ballots. The effect is the same as center-squeeze, where
your vote
gets "stuck" with a weak candidate who nevertheless has enough first
preferences to stay in the race for several rounds. By the time this
candidate is eliminated, the more-electable candidates with fewer
first
preferences have been defeated.
But from what I can tell, this is much trickier to resolve than
center-squeeze; proportional Condorcet methods don't seem to have
any
guarantees on how out-of-whack a coalition can get, although I think
Schulze STV has a nice local stability property.
Most ethnic minorities aren’t solid coalitions, although
African-Americans happen to be so overwhelmingly Democratic they
might
act like one. Something like PAV that approximately satisfies the
core
property should do better at giving minority voters more
representation.
On Thu, Jul 11, 2024 at 8:40 PM Richard, the VoteFair guy
<electionmethods@votefair.org
<mailto:electionmethods@votefair.org>
<mailto:electionmethods@votefair.org
<mailto:electionmethods@votefair.org>>> wrote:
On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:
> ... given there's no theoretical basis to think IRV would
affect
> city council and mayoral seats differently. ...
In the new Portland elections, "ranked choice voting" for
city-council
seats is STV (the Single Transferable Vote) with three seats per
district, whereas "ranked choice voting" for Portland mayor is
single-winner IRV (instant-runoff voting).
Of course Portland's three-seats-per-district STV city-council
elections
are going to yield more gender and racial diversity compared to
single-winner IRV for electing Portland's mayor.
Richard Fobes
On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:
> I'm going to go ahead and say I'm skeptical either of these
results will
> replicate, given there's no theoretical basis to think IRV
would affect
> city council and mayoral seats differently. My guess is
both results
> would disappear if you used a hierarchical/partial pooling
model to
> reduce the noise in the estimates.
>
> On Thu, Jul 11, 2024 at 10:45 AM Michael Garman
> <michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>>>>
> wrote:
>
> And that’s bad! But it doesn’t negate the point I made. In
council
> races it helps. And that’s good!
> On Thu, Jul 11, 2024 at 1:44 PM Closed Limelike Curves
> <closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>>
> <mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>>>> wrote:
>
> > In mayoral elections, RCV seems to decrease
gender and
> racial/ethnic diversity.
> Sounds substantial!
>
> On Thu, Jul 11, 2024 at 10:28 AM Michael Garman
> <michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>>
> <mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>>>> wrote:
>
> > In city council elections, RCV has a small but
positive
> effect on racial/ethnic diversity
> Sounds substantial!
>
> On Thu, Jul 11, 2024 at 1:26 PM Closed
Limelike Curves
<mailto:closed.limelike.curves@gmail.com>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>>
> <mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>>>> wrote:
>
> Empirically, IRV adoption has no substantial
effects on
> diversity
>
<https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/ <https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/> <https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/ <https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/>>>. 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.
>
> In general, the theoretical advantages of IRV
over FPP
> are outweighed by its practical costs (spoiled
ballots,
> lower trust in elections, cost, etc.).
> ----
> Election-Methods mailing list - see
> https://electorama.com/em https://electorama.com/em
<https://electorama.com/em <https://electorama.com/em>>
<https://electorama.com/em https://electorama.com/em
<https://electorama.com/em <https://electorama.com/em>>>
> for list info
>
----
Election-Methods mailing list - see https://electorama.com/em
<https://electorama.com/em>
<https://electorama.com/em https://electorama.com/em> for
list info
----
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<https://electorama.com/em> for list info
PSC is proportionality for solid coalitions
https://en.wikipedia.org/wiki/Proportionality_for_solid_coalitions.
On Tue, Jul 16, 2024 at 11:07 AM Richard, the VoteFair guy <
electionmethods@votefair.org> wrote:
On 7/15/2024 3:20 PM, Closed Limelike Curves wrote:
Richard, I'd suggest taking a look at the newest
version of Wikipedia's PSC article (and the
citations in there); ...
I don't recognize the PSC acronym.
And I can't find it in Wikipedia's PSC list:
https://en.wikipedia.org/wiki/PSC
Also, I suggest changing the email "subject" to the full name of
whatever PSC is.
Richard Fobes
On 7/15/2024 3:20 PM, Closed Limelike Curves wrote:
Richard, I'd suggest taking a look at the newest version of Wikipedia's
PSC article (and the citations in there); nonpartisan PR algorithms
other than STV are a very new field of research, and we're just barely
starting to study what algorithms satisfy what proportionality axioms.
STV does try to put together a coalition, but this involves a very basic
greedy search for cohesive/solid coalitions that support a single group
of candidates. e.g. say a Hispanic Republican's preferences are
something like "vote for a Hispanic Republican, then non-Hispanic
Republicans, then a Hispanic Democrat"; whereas others Hispanic
Republicans care more about ethnicity than about party. In this
situation, there's no solid coalition for Hispanics /or/ Republicans, so
it's very prone to underrepresent one of these groups. IIRC the EVC's
proposal for a proportional STAR algorithm works on basically the same
principle, as does anything that assigns seats sequentially/greedily,
which is why I tend to dislike them; whereas PAV is optimization-based,
so it tends to find better apportionments across cross-cutting
coalitions. I think Schulze STV also satisfies similar properties (but
only locally, because global optimization across committees requires
voters to give candidates ratings).
On Sun, Jul 14, 2024 at 10:22 AM Richard, the VoteFair guy
<electionmethods@votefair.org mailto:electionmethods@votefair.org>
wrote:
On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:
... my guess is the effect of STV is probably going to be
limited
compared to other methods, because STV is only proportional for
solid
coalitions, i.e. voting blocs moving in perfect lockstep with
each
other, and only if they exceed a full quota. ...
When using STV, coalitions don't need to be "solid."
STV calculations automatically identify de-facto "coalitions." Each
candidate can be thought of as a de-facto coalition.
One way to think of this concept is that STV gives any coalition a
"second try" when filling the second seat, and a "third try" when
filling the third seat.
In contrast, IRV provides only "one try" for a coalition to elect
their
candidate. So for IRV, a "solid" coalition voting with the same
tactic
does have an advantage compared to a loose (non-solid) coalition.
I'm not saying STV is better than PAV. I'm saying this specific
criticism of STV -- thinking that a coalition must be "solid" -- is
not
a valid reason to dismiss STV.
Richard Fobes
On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:
Ahh, yeah, any PR method will outperform winner-take-all on this
metric.
If cities are using STV for their city councils, that might imply
single-winner IRV actively reduces minority representation.
That said, my guess is the effect of STV is probably going to be
limited
compared to other methods, because STV is only proportional for
solid
coalitions, i.e. voting blocs moving in perfect lockstep with each
other, and only if they exceed a full quota. So, for example, if
ethnic
minorities tend to vote for a mix of white and minority
candidates, or
if they're split across party lines (e.g. Hispanics only go about
60-40
for Democrats), this will tend to break up and dilute their
interests.
It's not enough to have a quota of Hispanics who rate Hispanic
Republicans and Hispanic Democrats highly; you need to have a
full quota
rank /either/ a Hispanic Republican or a Hispanic Democrat at the
top of
their ballots. The effect is the same as center-squeeze, where
your vote
gets "stuck" with a weak candidate who nevertheless has enough
first
preferences to stay in the race for several rounds. By the time
this
candidate is eliminated, the more-electable candidates with fewer
first
preferences have been defeated.
But from what I can tell, this is much trickier to resolve than
center-squeeze; proportional Condorcet methods don't seem to have
any
guarantees on how out-of-whack a coalition can get, although I
think
Schulze STV has a nice local stability property.
Most ethnic minorities aren’t solid coalitions, although
African-Americans happen to be so overwhelmingly Democratic they
might
act like one. Something like PAV that approximately satisfies the
core
property should do better at giving minority voters more
representation.
On Thu, Jul 11, 2024 at 8:40 PM Richard, the VoteFair guy
<electionmethods@votefair.org
<mailto:electionmethods@votefair.org>
<mailto:electionmethods@votefair.org
<mailto:electionmethods@votefair.org>>> wrote:
On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:
... given there's no theoretical basis to think IRV would
affect
city council and mayoral seats differently. ...
In the new Portland elections, "ranked choice voting" for
city-council
seats is STV (the Single Transferable Vote) with three seats
per
district, whereas "ranked choice voting" for Portland mayor is
single-winner IRV (instant-runoff voting).
Of course Portland's three-seats-per-district STV city-council
elections
are going to yield more gender and racial diversity compared
to
single-winner IRV for electing Portland's mayor.
Richard Fobes
On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:
I'm going to go ahead and say I'm skeptical either of these
results will
replicate, given there's no theoretical basis to think IRV
would affect
city council and mayoral seats differently. My guess is
both results
would disappear if you used a hierarchical/partial pooling
model to
reduce the noise in the estimates.
On Thu, Jul 11, 2024 at 10:45 AM Michael Garman
<michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>>>>
wrote:
And that’s bad! But it doesn’t negate the point I
made. In
council
races it helps. And that’s good!
On Thu, Jul 11, 2024 at 1:44 PM Closed Limelike Curves
<closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>>>> wrote:
In mayoral elections, RCV seems to decrease
gender and
racial/ethnic diversity.
Sounds substantial!
On Thu, Jul 11, 2024 at 10:28 AM Michael Garman
<michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>
<mailto:michael.garman@rankthevote.us
<mailto:michael.garman@rankthevote.us>>>> wrote:
In city council elections, RCV has a small
but
positive
effect on racial/ethnic diversity
Sounds substantial!
On Thu, Jul 11, 2024 at 1:26 PM Closed
Limelike Curves
<closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>
<mailto:closed.limelike.curves@gmail.com
<mailto:closed.limelike.curves@gmail.com>>>> wrote:
Empirically, IRV adoption has no
substantial
effects on
diversity
<
https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/
<
https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/>
<
https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/
<
https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/>>>.
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.
In general, the theoretical advantages of
IRV
over FPP
are outweighed by its practical costs
(spoiled
ballots,
lower trust in elections, cost, etc.).
----
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<https://electorama.com/em <https://electorama.com/em>>
<https://electorama.com/em <https://electorama.com/em>
<https://electorama.com/em <https://electorama.com/em>>>
for list info
----
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<https://electorama.com/em>
<https://electorama.com/em <https://electorama.com/em>> for
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----
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<https://electorama.com/em> for list info
Election-Methods mailing list - see https://electorama.com/em for list
info
PSC is proportionality for solid coalitions
https://en.wikipedia.org/wiki/Proportionality_for_solid_coalitions.
That link is to a rubbish page.
There is a proper criterion called Droop Proportionality for Solid
coalitions. Douglas Woodall from 1994:
The most important single property of STV is what I call the/Droop
proportionality criterion/or/DPC/. Recall that if/v/votes are cast in
an election to fill/s/seats, then the quantity/v//(/s/+ 1) is called
the/Droop quota/.
- *DPC.*If, for some whole numbers/k/and/m/satisfying 0 </k/<=/m/,
more than/k/Droop quotas of voters put the same/m/candidates (not
necessarily in the same order) as the top/m/candidates in their
preference listings, then at least/k/of those/m/candidates should
be elected. (In the event of a tie, this should be interpreted as
saying that every outcome that is chosen with non-zero probability
should include at least/k/of these/m/candidates.)
In statements of properties, the word "should" indicates that the
property says that something should happen, not necessarily that I
personally agree. However, in this case I certainly do: DPC seems to
me to be a/sine qua non/for a fair election rule. I suggest that any
system that satisfies DPC deserves to be called
a/quota-preferential/system and to be regarded as a system of
proportional representation (within each constituency)-an
STV-lookalike. Conversely, I assume that no member of the Electoral
Reform Society will be satisfied with anything that does not satisfy DPC.
The property to which DPC reduces in a single-seat election should
hold (as a consequence of DPC) even in a multi-seat election, and it
deserves a special name.
- *Majority.*If more than half the voters put the same set of
candidates (not necessarily in the same order) at the top of their
preference listings, then at least one of those candidates should
be elected.
http://www.mcdougall.org.uk/voting-matters/ISSUE3/P5.HTM
Later he was calling that single-winner version "Majority for Solid
Coalitions", presumably because others were using "Majority" to mean
Majority for a Single Candidate and it's useful to have something short
that means that.
On 19/07/2024 7:00 am, Closed Limelike Curves wrote:
PSC is proportionality for solid coalitions
https://en.wikipedia.org/wiki/Proportionality_for_solid_coalitions.
On Tue, Jul 16, 2024 at 11:07 AM Richard, the VoteFair guy
electionmethods@votefair.org wrote:
On 7/15/2024 3:20 PM, Closed Limelike Curves wrote:
> Richard, I'd suggest taking a look at the newest
> version of Wikipedia's PSC article (and the
> citations in there); ...
I don't recognize the PSC acronym.
And I can't find it in Wikipedia's PSC list:
https://en.wikipedia.org/wiki/PSC
Also, I suggest changing the email "subject" to the full name of
whatever PSC is.
Richard Fobes
On 7/15/2024 3:20 PM, Closed Limelike Curves wrote:
Richard, I'd suggest taking a look at the newest version of
Wikipedia's
PSC article (and the citations in there); nonpartisan PR algorithms
other than STV are a very new field of research, and we're just
barely
starting to study what algorithms satisfy what proportionality
axioms.
STV does try to put together a coalition, but this involves a
very basic
greedy search for cohesive/solid coalitions that support a
single group
of candidates. e.g. say a Hispanic Republican's preferences are
something like "vote for a Hispanic Republican, then non-Hispanic
Republicans, then a Hispanic Democrat"; whereas others Hispanic
Republicans care more about ethnicity than about party. In this
situation, there's no solid coalition for Hispanics /or/
Republicans, so
it's very prone to underrepresent one of these groups. IIRC the
EVC's
proposal for a proportional STAR algorithm works on basically
the same
principle, as does anything that assigns seats
sequentially/greedily,
which is why I tend to dislike them; whereas PAV is
optimization-based,
so it tends to find better apportionments across cross-cutting
coalitions. I think Schulze STV also satisfies similar
properties (but
only locally, because global optimization across committees
requires
voters to give candidates ratings).
On Sun, Jul 14, 2024 at 10:22 AM Richard, the VoteFair guy
<electionmethods@votefair.org
<mailto:electionmethods@votefair.org>> wrote:
On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:
> ... my guess is the effect of STV is probably going to
be limited
> compared to other methods, because STV is only
proportional for
solid
> coalitions, i.e. voting blocs moving in perfect lockstep
with each
> other, and only if they exceed a full quota. ...
When using STV, coalitions don't need to be "solid."
STV calculations automatically identify de-facto
"coalitions." Each
candidate can be thought of as a de-facto coalition.
One way to think of this concept is that STV gives any
coalition a
"second try" when filling the second seat, and a "third try"
when
filling the third seat.
In contrast, IRV provides only "one try" for a coalition to
elect their
candidate. So for IRV, a "solid" coalition voting with the
same tactic
does have an advantage compared to a loose (non-solid)
coalition.
I'm not saying STV is better than PAV. I'm saying this specific
criticism of STV -- thinking that a coalition must be
"solid" -- is not
a valid reason to dismiss STV.
Richard Fobes
On 7/13/2024 5:39 PM, Closed Limelike Curves wrote:
> Ahh, yeah, any PR method will outperform winner-take-all
on this
metric.
> If cities are using STV for their city councils, that
might imply
> single-winner IRV actively reduces minority representation.
>
> That said, my guess is the effect of STV is probably
going to be
limited
> compared to other methods, because STV is only
proportional for
solid
> coalitions, i.e. voting blocs moving in perfect lockstep
with each
> other, and only if they exceed a full quota. So, for
example, if
ethnic
> minorities tend to vote for a mix of white and minority
candidates, or
> if they're split across party lines (e.g. Hispanics only
go about
60-40
> for Democrats), this will tend to break up and dilute their
interests.
> It's not enough to have a quota of Hispanics who rate
Hispanic
> Republicans and Hispanic Democrats highly; you need to have a
full quota
> rank /either/ a Hispanic Republican or a Hispanic
Democrat at the
top of
> their ballots. The effect is the same as center-squeeze,
where
your vote
> gets "stuck" with a weak candidate who nevertheless has
enough first
> preferences to stay in the race for several rounds. By
the time this
> candidate is eliminated, the more-electable candidates
with fewer
first
> preferences have been defeated.
>
> But from what I can tell, this is much trickier to
resolve than
> center-squeeze; proportional Condorcet methods don't seem
to have
any
> guarantees on how out-of-whack a coalition can get,
although I think
> Schulze STV has a nice local stability property.
>
> Most ethnic minorities aren’t solid coalitions, although
> African-Americans happen to be so overwhelmingly
Democratic they
might
> act like one. Something like PAV that approximately
satisfies the
core
> property should do better at giving minority voters more
representation.
>
> On Thu, Jul 11, 2024 at 8:40 PM Richard, the VoteFair guy
> <electionmethods@votefair.org
mailto:electionmethods@votefair.org
<mailto:electionmethods@votefair.org
mailto:electionmethods@votefair.org>> wrote:
>
> On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:
> > ... given there's no theoretical basis to think
IRV would
affect
> > city council and mayoral seats differently. ...
>
> In the new Portland elections, "ranked choice voting" for
city-council
> seats is STV (the Single Transferable Vote) with
three seats per
> district, whereas "ranked choice voting" for Portland
mayor is
> single-winner IRV (instant-runoff voting).
>
> Of course Portland's three-seats-per-district STV
city-council
> elections
> are going to yield more gender and racial diversity
compared to
> single-winner IRV for electing Portland's mayor.
>
> Richard Fobes
>
>
> On 7/11/2024 10:47 AM, Closed Limelike Curves wrote:
> > I'm going to go ahead and say I'm skeptical either
of these
> results will
> > replicate, given there's no theoretical basis to
think IRV
> would affect
> > city council and mayoral seats differently. My
guess is
both results
> > would disappear if you used a hierarchical/partial
pooling
model to
> > reduce the noise in the estimates.
> >
> > On Thu, Jul 11, 2024 at 10:45 AM Michael Garman
> > <michael.garman@rankthevote.us
mailto:michael.garman@rankthevote.us
> <mailto:michael.garman@rankthevote.us
mailto:michael.garman@rankthevote.us>
> <mailto:michael.garman@rankthevote.us
mailto:michael.garman@rankthevote.us
> <mailto:michael.garman@rankthevote.us
mailto:michael.garman@rankthevote.us>>>
> > wrote:
> >
> > And that’s bad! But it doesn’t negate the
point I made. In
> council
> > races it helps. And that’s good!
> > On Thu, Jul 11, 2024 at 1:44 PM Closed
Limelike Curves
> > <closed.limelike.curves@gmail.com
mailto:closed.limelike.curves@gmail.com
> <mailto:closed.limelike.curves@gmail.com
mailto:closed.limelike.curves@gmail.com>
> > <mailto:closed.limelike.curves@gmail.com
mailto:closed.limelike.curves@gmail.com
> <mailto:closed.limelike.curves@gmail.com
mailto:closed.limelike.curves@gmail.com>>> wrote:
> >
> > > In mayoral elections, RCV seems to
*decrease*
gender and
> > racial/ethnic diversity.
> > Sounds substantial!
> >
> > On Thu, Jul 11, 2024 at 10:28 AM Michael
Garman
> > <michael.garman@rankthevote.us
mailto:michael.garman@rankthevote.us
> <mailto:michael.garman@rankthevote.us
mailto:michael.garman@rankthevote.us>
> > <mailto:michael.garman@rankthevote.us
mailto:michael.garman@rankthevote.us
> <mailto:michael.garman@rankthevote.us
mailto:michael.garman@rankthevote.us>>> wrote:
> >
> > > In city council elections, RCV has
a small but
> positive
> > effect on racial/ethnic diversity
> > Sounds substantial!
> >
> > On Thu, Jul 11, 2024 at 1:26 PM Closed
Limelike Curves
> > <closed.limelike.curves@gmail.com
mailto:closed.limelike.curves@gmail.com
> <mailto:closed.limelike.curves@gmail.com
mailto:closed.limelike.curves@gmail.com>
> > <mailto:closed.limelike.curves@gmail.com
mailto:closed.limelike.curves@gmail.com
> <mailto:closed.limelike.curves@gmail.com
mailto:closed.limelike.curves@gmail.com>>> wrote:
> >
> > Empirically, IRV adoption has no
substantial
> effects on
> > diversity
> >
>
<https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/
<https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/>
<https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/
<https://www.newamerica.org/political-reform/reports/rcv-impact-on-candidate-entry-and-representation/>>>.
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.
> >
> > In general, the theoretical
advantages of IRV
> over FPP
> > are outweighed by its practical
costs (spoiled
> ballots,
> > lower trust in elections, cost, etc.).
> > ----
> > Election-Methods mailing list - see
> > https://electorama.com/em https://electorama.com/em
<https://electorama.com/em https://electorama.com/em>
> <https://electorama.com/em https://electorama.com/em
<https://electorama.com/em https://electorama.com/em>>
> > for list info
> >
> ----
> Election-Methods mailing list - see
https://electorama.com/em
https://electorama.com/em
> <https://electorama.com/em
<https://electorama.com/em>> for
list info
>
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Election-Methods mailing list - see https://electorama.com/em
https://electorama.com/em for list info
----
Election-Methods mailing list - see https://electorama.com/em for
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