[EM] Single Non-Transferable voting + Approval (or Approval Sorted Margins) as a primary

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[EM] Single Non-Transferable voting + Approval (or Approval Sorted Margins) as a primary

Ted Stern
Over the years a number of people on this list (e.g. Rob Lanphier, myself and others) have proposed various methods for using Approval in primary elections.

There are arguments to be made for using other PR methods, but it seems to me that SNTV is ideally suited to be a primary method, since it resists pushover and doesn't tend to overrepresent parties.

Using Approval as a base method, single non-transferable approval voting would look like
  • Advance Approval winner and Approval runner-up
  • Deweight to zero all ballots approving of AW.
  • Repeat until some threshold (e.g. 90%) of ballots have been used up:
    • Advance approval winner on the current remaining ballots
    • Deweight ballots approving of latest winner to zero
The advantages here are 
  • Relative simplicity -- No complicated reweighting algorithms, so each recount for the next approval winner is faster than the previous, and can even be done by hand.
  • Each winner (other than the first approval runner-up) will tend to be from a different party or faction of a party.  There may be some overlap from also advancing the overall Approval runner-up, but if the total AW and ARU are from the same party, it gives them an advantage under Approval to have a similar candidate for comparison. 
  • Most groups will be represented in the General election.
  • Pushover strategy is disincentivized by complete deweighting, so parties should not be threatened by strategic promotion of their worst candidate. There is some possibility that voters would do that regardless, but the effect should be no worse than in current top-two elections.
  • Modifications could include:
    • Stop advancing candidates when the highest approval on remaining ballots drops below a threshold. For example, if the total deweight threshold is 90%, if the latest winner has less than 5% approval on remaining ballots (half the complement of 90%), break the loop.
    • Stop when a certain number of candidates have advanced. For example, if using the 5% rule above, it is possible that 10 to 15 candidates could advance to the General, defeating the winnowing purpose of a primary. It seems reasonable to stop at 5 or 6 candidates.
    • Use a different method other than simple Approval.
I would be perfectly satisfied to have SNTAV as a primary method, but if one can handle a bit more complexity (say in smaller groups), it would be reasonable to use Approval Sorted Margins as the base method:

  • Use Ranked or Rated ballots with explicit Approval Cutoff. If not explicitly specified, cutoff is at zero-rating or last ranking.
  • Advance Approval Sorted Margins winner to general election 
  • Deweight to zero all ballots approving of AW.
  • Repeat until some threshold (e.g. 90%) of ballots have been used up:
    • Advance ASM winner on the current remaining ballots
    • Deweight ballots approving of latest winner to zero
For public elections, I think the SNTAV approach I outline above, with a 90% threshold, 5% minimum remaining approval, and limited to 6 candidates (4 approval winners and 1 top approval runner-up) gives enough room to enable more parties to develop.

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Re: [EM] Single Non-Transferable voting + Approval (or Approval Sorted Margins) as a primary

Ted Stern
I've implemented the primary idea I proposed last month. It's available in my github repository as winnow.py. The repo is located at

https://github.com/dodecatheon/approval-sorted-margins/

The code is designed to be used as a test bed for several score-ballot-based methods.

The default method for advancing candidates is Preference Approval Sorted Margins.  It's basically Approval Sorted Margins, but I interpret any non-zero score as approval, so I'm calling the higher level of approval "Preference". As I proposed before, any ballots approving (non-zero score) of the currently advancing winner are removed completely, then tallies are done on the remaining ballots until no more candidates remain or 95% of the ballots are used up, or a maximum number of candidates (default 7) has been reached.  In each candidate advance round, candidates with remaining approval below the threshold (default 1%) are dropped.

Approval, Score, STAR, Vote 3-2-1, and Score Sorted Margins are supported, and just for the sake of completeness, I also include Preference (like approval but using explicit "preference" cutoff), and Top-rating.

It is designed to be used on a linux command line with python 3.7+ that includes numpy.  I recommend getting the Anaconda (or mini-conda) package.  There are a lot of commandline options.

From the standpoint of practicality, say in the event of a 100+ candidate jungle primary, this type of primary would be relatively simple to implement for Approval, Score, Preference or Top-Rating.  Slightly more difficult would be STAR or Vote 3-2-1.  Finally, any method that requires the pairwise array, such as PASM or SSM, would be most complicated, and would probably require some sort of candidate pruning below an approval threshold (to get the number of candidates below 20 or so) to be at all feasible.

On Fri, Aug 7, 2020 at 2:33 PM Ted Stern <[hidden email]> wrote:
Over the years a number of people on this list (e.g. Rob Lanphier, myself and others) have proposed various methods for using Approval in primary elections.

There are arguments to be made for using other PR methods, but it seems to me that SNTV is ideally suited to be a primary method, since it resists pushover and doesn't tend to overrepresent parties.

Using Approval as a base method, single non-transferable approval voting would look like
  • Advance Approval winner and Approval runner-up
  • Deweight to zero all ballots approving of AW.
  • Repeat until some threshold (e.g. 90%) of ballots have been used up:
    • Advance approval winner on the current remaining ballots
    • Deweight ballots approving of latest winner to zero
The advantages here are 
  • Relative simplicity -- No complicated reweighting algorithms, so each recount for the next approval winner is faster than the previous, and can even be done by hand.
  • Each winner (other than the first approval runner-up) will tend to be from a different party or faction of a party.  There may be some overlap from also advancing the overall Approval runner-up, but if the total AW and ARU are from the same party, it gives them an advantage under Approval to have a similar candidate for comparison. 
  • Most groups will be represented in the General election.
  • Pushover strategy is disincentivized by complete deweighting, so parties should not be threatened by strategic promotion of their worst candidate. There is some possibility that voters would do that regardless, but the effect should be no worse than in current top-two elections.
  • Modifications could include:
    • Stop advancing candidates when the highest approval on remaining ballots drops below a threshold. For example, if the total deweight threshold is 90%, if the latest winner has less than 5% approval on remaining ballots (half the complement of 90%), break the loop.
    • Stop when a certain number of candidates have advanced. For example, if using the 5% rule above, it is possible that 10 to 15 candidates could advance to the General, defeating the winnowing purpose of a primary. It seems reasonable to stop at 5 or 6 candidates.
    • Use a different method other than simple Approval.
I would be perfectly satisfied to have SNTAV as a primary method, but if one can handle a bit more complexity (say in smaller groups), it would be reasonable to use Approval Sorted Margins as the base method:

  • Use Ranked or Rated ballots with explicit Approval Cutoff. If not explicitly specified, cutoff is at zero-rating or last ranking.
  • Advance Approval Sorted Margins winner to general election 
  • Deweight to zero all ballots approving of AW.
  • Repeat until some threshold (e.g. 90%) of ballots have been used up:
    • Advance ASM winner on the current remaining ballots
    • Deweight ballots approving of latest winner to zero
For public elections, I think the SNTAV approach I outline above, with a 90% threshold, 5% minimum remaining approval, and limited to 6 candidates (4 approval winners and 1 top approval runner-up) gives enough room to enable more parties to develop.

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Re: [EM] Single Non-Transferable voting + Approval (or Approval Sorted Margins) as a primary

C.Benham

Ted,

I haven't been thinking very much about this topic lately.  But I have one or two ideas.  

Abolish the party primaries and just have one big "primary".   Use  STV to one-at -a-time eliminate candidates until the remaining candidate with the fewest votes has a tally that is at least X (say 15)%
of the total of the unexhausted ballots (i.e. those that show some preference among uneliminated candidates).

In the "general election" this should limit the field to a manageable number (no more than 6).

("STAR" is an abomination.)

At least as important in the current period  is election integrity and thinking of ways to use technology to implement direct democracy or some hybrid of direct and representative democracy.

Chris


On 18/09/2020 6:13 am, Ted Stern wrote:
I've implemented the primary idea I proposed last month. It's available in my github repository as winnow.py. The repo is located at

https://github.com/dodecatheon/approval-sorted-margins/

The code is designed to be used as a test bed for several score-ballot-based methods.

The default method for advancing candidates is Preference Approval Sorted Margins.  It's basically Approval Sorted Margins, but I interpret any non-zero score as approval, so I'm calling the higher level of approval "Preference". As I proposed before, any ballots approving (non-zero score) of the currently advancing winner are removed completely, then tallies are done on the remaining ballots until no more candidates remain or 95% of the ballots are used up, or a maximum number of candidates (default 7) has been reached.  In each candidate advance round, candidates with remaining approval below the threshold (default 1%) are dropped.

Approval, Score, STAR, Vote 3-2-1, and Score Sorted Margins are supported, and just for the sake of completeness, I also include Preference (like approval but using explicit "preference" cutoff), and Top-rating.

It is designed to be used on a linux command line with python 3.7+ that includes numpy.  I recommend getting the Anaconda (or mini-conda) package.  There are a lot of commandline options.

From the standpoint of practicality, say in the event of a 100+ candidate jungle primary, this type of primary would be relatively simple to implement for Approval, Score, Preference or Top-Rating.  Slightly more difficult would be STAR or Vote 3-2-1.  Finally, any method that requires the pairwise array, such as PASM or SSM, would be most complicated, and would probably require some sort of candidate pruning below an approval threshold (to get the number of candidates below 20 or so) to be at all feasible.

On Fri, Aug 7, 2020 at 2:33 PM Ted Stern <[hidden email]> wrote:
Over the years a number of people on this list (e.g. Rob Lanphier, myself and others) have proposed various methods for using Approval in primary elections.

There are arguments to be made for using other PR methods, but it seems to me that SNTV is ideally suited to be a primary method, since it resists pushover and doesn't tend to overrepresent parties.

Using Approval as a base method, single non-transferable approval voting would look like
  • Advance Approval winner and Approval runner-up
  • Deweight to zero all ballots approving of AW.
  • Repeat until some threshold (e.g. 90%) of ballots have been used up:
    • Advance approval winner on the current remaining ballots
    • Deweight ballots approving of latest winner to zero
The advantages here are 
  • Relative simplicity -- No complicated reweighting algorithms, so each recount for the next approval winner is faster than the previous, and can even be done by hand.
  • Each winner (other than the first approval runner-up) will tend to be from a different party or faction of a party.  There may be some overlap from also advancing the overall Approval runner-up, but if the total AW and ARU are from the same party, it gives them an advantage under Approval to have a similar candidate for comparison. 
  • Most groups will be represented in the General election.
  • Pushover strategy is disincentivized by complete deweighting, so parties should not be threatened by strategic promotion of their worst candidate. There is some possibility that voters would do that regardless, but the effect should be no worse than in current top-two elections.
  • Modifications could include:
    • Stop advancing candidates when the highest approval on remaining ballots drops below a threshold. For example, if the total deweight threshold is 90%, if the latest winner has less than 5% approval on remaining ballots (half the complement of 90%), break the loop.
    • Stop when a certain number of candidates have advanced. For example, if using the 5% rule above, it is possible that 10 to 15 candidates could advance to the General, defeating the winnowing purpose of a primary. It seems reasonable to stop at 5 or 6 candidates.
    • Use a different method other than simple Approval.
I would be perfectly satisfied to have SNTAV as a primary method, but if one can handle a bit more complexity (say in smaller groups), it would be reasonable to use Approval Sorted Margins as the base method:

  • Use Ranked or Rated ballots with explicit Approval Cutoff. If not explicitly specified, cutoff is at zero-rating or last ranking.
  • Advance Approval Sorted Margins winner to general election 
  • Deweight to zero all ballots approving of AW.
  • Repeat until some threshold (e.g. 90%) of ballots have been used up:
    • Advance ASM winner on the current remaining ballots
    • Deweight ballots approving of latest winner to zero
For public elections, I think the SNTAV approach I outline above, with a 90% threshold, 5% minimum remaining approval, and limited to 6 candidates (4 approval winners and 1 top approval runner-up) gives enough room to enable more parties to develop.

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Re: [EM] Single Non-Transferable voting + Approval (or Approval Sorted Margins) as a primary

robert bristow-johnson


> On 09/18/2020 12:48 PM C.Benham <[hidden email]> wrote:
>
>
> Ted,
>  
>  I haven't been thinking very much about this topic lately. But I have one or two ideas.
>  
>  Abolish the party primaries and just have one big "primary".

Ain't that what they do in California?  They call it their "Open primary".

Problem is, some people are alarmed with there is absolutely no one from their party on the general election ballot.  (Admittedly, they were Republicans, but they were not happy that the only choice they could have was between various Democrats *on* *the* *general* *election* *ballot*.)

I think every party has a right to put their best foot forward, select among themselves the best candidate (from their POV) to put on the ballot.  Of course everyone, whether they are major party, minor party, or independent, must satisfy ballot access requirements (sufficient number of valid signatures on a petition).

But I ain't for the Open Primary.

--

r b-j                  [hidden email]

"Imagination is more important than knowledge."
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Re: [EM] Single Non-Transferable voting + Approval (or Approval Sorted Margins) as a primary

Richard Lung
In reply to this post by C.Benham
Hoag and Hallett , in their at-large city elections said STV had built-in primaries, so you didn't need separate elections.

Richard L.


On 18 Sep 2020, at 9:48 am, C.Benham <[hidden email]> wrote:

Ted,

I haven't been thinking very much about this topic lately.  But I have one or two ideas.  

Abolish the party primaries and just have one big "primary".   Use  STV to one-at -a-time eliminate candidates until the remaining candidate with the fewest votes has a tally that is at least X (say 15)%
of the total of the unexhausted ballots (i.e. those that show some preference among uneliminated candidates).

In the "general election" this should limit the field to a manageable number (no more than 6).

("STAR" is an abomination.)

At least as important in the current period  is election integrity and thinking of ways to use technology to implement direct democracy or some hybrid of direct and representative democracy.

Chris


On 18/09/2020 6:13 am, Ted Stern wrote:
I've implemented the primary idea I proposed last month. It's available in my github repository as winnow.py. The repo is located at

https://github.com/dodecatheon/approval-sorted-margins/

The code is designed to be used as a test bed for several score-ballot-based methods.

The default method for advancing candidates is Preference Approval Sorted Margins.  It's basically Approval Sorted Margins, but I interpret any non-zero score as approval, so I'm calling the higher level of approval "Preference". As I proposed before, any ballots approving (non-zero score) of the currently advancing winner are removed completely, then tallies are done on the remaining ballots until no more candidates remain or 95% of the ballots are used up, or a maximum number of candidates (default 7) has been reached.  In each candidate advance round, candidates with remaining approval below the threshold (default 1%) are dropped.

Approval, Score, STAR, Vote 3-2-1, and Score Sorted Margins are supported, and just for the sake of completeness, I also include Preference (like approval but using explicit "preference" cutoff), and Top-rating.

It is designed to be used on a linux command line with python 3.7+ that includes numpy.  I recommend getting the Anaconda (or mini-conda) package.  There are a lot of commandline options.

From the standpoint of practicality, say in the event of a 100+ candidate jungle primary, this type of primary would be relatively simple to implement for Approval, Score, Preference or Top-Rating.  Slightly more difficult would be STAR or Vote 3-2-1.  Finally, any method that requires the pairwise array, such as PASM or SSM, would be most complicated, and would probably require some sort of candidate pruning below an approval threshold (to get the number of candidates below 20 or so) to be at all feasible.

On Fri, Aug 7, 2020 at 2:33 PM Ted Stern <[hidden email]> wrote:
Over the years a number of people on this list (e.g. Rob Lanphier, myself and others) have proposed various methods for using Approval in primary elections.

There are arguments to be made for using other PR methods, but it seems to me that SNTV is ideally suited to be a primary method, since it resists pushover and doesn't tend to overrepresent parties.

Using Approval as a base method, single non-transferable approval voting would look like
  • Advance Approval winner and Approval runner-up
  • Deweight to zero all ballots approving of AW.
  • Repeat until some threshold (e.g. 90%) of ballots have been used up:
    • Advance approval winner on the current remaining ballots
    • Deweight ballots approving of latest winner to zero
The advantages here are 
  • Relative simplicity -- No complicated reweighting algorithms, so each recount for the next approval winner is faster than the previous, and can even be done by hand.
  • Each winner (other than the first approval runner-up) will tend to be from a different party or faction of a party.  There may be some overlap from also advancing the overall Approval runner-up, but if the total AW and ARU are from the same party, it gives them an advantage under Approval to have a similar candidate for comparison. 
  • Most groups will be represented in the General election.
  • Pushover strategy is disincentivized by complete deweighting, so parties should not be threatened by strategic promotion of their worst candidate. There is some possibility that voters would do that regardless, but the effect should be no worse than in current top-two elections.
  • Modifications could include:
    • Stop advancing candidates when the highest approval on remaining ballots drops below a threshold. For example, if the total deweight threshold is 90%, if the latest winner has less than 5% approval on remaining ballots (half the complement of 90%), break the loop.
    • Stop when a certain number of candidates have advanced. For example, if using the 5% rule above, it is possible that 10 to 15 candidates could advance to the General, defeating the winnowing purpose of a primary. It seems reasonable to stop at 5 or 6 candidates.
    • Use a different method other than simple Approval.
I would be perfectly satisfied to have SNTAV as a primary method, but if one can handle a bit more complexity (say in smaller groups), it would be reasonable to use Approval Sorted Margins as the base method:

  • Use Ranked or Rated ballots with explicit Approval Cutoff. If not explicitly specified, cutoff is at zero-rating or last ranking.
  • Advance Approval Sorted Margins winner to general election 
  • Deweight to zero all ballots approving of AW.
  • Repeat until some threshold (e.g. 90%) of ballots have been used up:
    • Advance ASM winner on the current remaining ballots
    • Deweight ballots approving of latest winner to zero
For public elections, I think the SNTAV approach I outline above, with a 90% threshold, 5% minimum remaining approval, and limited to 6 candidates (4 approval winners and 1 top approval runner-up) gives enough room to enable more parties to develop.
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Re: [EM] Single Non-Transferable voting + Approval (or Approval Sorted Margins) as a primary

Ted Stern
In reply to this post by C.Benham
Hi Chris,

Taking your points in reverse order:

Direct democracy would be great, but in the US, at least, it's a long way off until we can elect representatives who will put us on the path to get there.

I wouldn't call STAR an abomination, but it doesn't seem to have a firm foothold in either utilitarian or majoritarian philosophies, and IMO it fails to find the centroid of voter sentiment even in an idealized framework like Yee plots.

The proposed method was intended to be a winnowing election in the case that there are more than 7 candidates, and remove some clone-type of duplication of candidates at the same time.  So yes, it would replace all party primaries.  Robert Bristow-Johnson points out that California has an open primary. Yes, I am aware of that -- Washington State's is similar. It is a top two single vote primary.  The problem with that is, as pointed out by Robert and Richard, that some parties might not be represented. Hence the winnowing primary, allowing more candidates to represent a larger portion of the electorate.

STV is an interesting idea, although in the sense you describe it, it looks more like extended IRV. I would like to see someone implement that, but the other aspect of my testbed script is that it uses score ballots, and I don't see an easy way to do that.  But STV at least has the virtue of being hand-countable. I would run it until the smallest candidate total is above 5%, though, up to a max of 7 candidates instead of 6. 

Ted


On Fri, Sep 18, 2020 at 9:48 AM C.Benham <[hidden email]> wrote:

Ted,

I haven't been thinking very much about this topic lately.  But I have one or two ideas.  

Abolish the party primaries and just have one big "primary".   Use  STV to one-at -a-time eliminate candidates until the remaining candidate with the fewest votes has a tally that is at least X (say 15)%
of the total of the unexhausted ballots (i.e. those that show some preference among uneliminated candidates).

In the "general election" this should limit the field to a manageable number (no more than 6).

("STAR" is an abomination.)

At least as important in the current period  is election integrity and thinking of ways to use technology to implement direct democracy or some hybrid of direct and representative democracy.

Chris


On 18/09/2020 6:13 am, Ted Stern wrote:
I've implemented the primary idea I proposed last month. It's available in my github repository as winnow.py. The repo is located at

https://github.com/dodecatheon/approval-sorted-margins/

The code is designed to be used as a test bed for several score-ballot-based methods.

The default method for advancing candidates is Preference Approval Sorted Margins.  It's basically Approval Sorted Margins, but I interpret any non-zero score as approval, so I'm calling the higher level of approval "Preference". As I proposed before, any ballots approving (non-zero score) of the currently advancing winner are removed completely, then tallies are done on the remaining ballots until no more candidates remain or 95% of the ballots are used up, or a maximum number of candidates (default 7) has been reached.  In each candidate advance round, candidates with remaining approval below the threshold (default 1%) are dropped.

Approval, Score, STAR, Vote 3-2-1, and Score Sorted Margins are supported, and just for the sake of completeness, I also include Preference (like approval but using explicit "preference" cutoff), and Top-rating.

It is designed to be used on a linux command line with python 3.7+ that includes numpy.  I recommend getting the Anaconda (or mini-conda) package.  There are a lot of commandline options.

From the standpoint of practicality, say in the event of a 100+ candidate jungle primary, this type of primary would be relatively simple to implement for Approval, Score, Preference or Top-Rating.  Slightly more difficult would be STAR or Vote 3-2-1.  Finally, any method that requires the pairwise array, such as PASM or SSM, would be most complicated, and would probably require some sort of candidate pruning below an approval threshold (to get the number of candidates below 20 or so) to be at all feasible.

On Fri, Aug 7, 2020 at 2:33 PM Ted Stern <[hidden email]> wrote:
Over the years a number of people on this list (e.g. Rob Lanphier, myself and others) have proposed various methods for using Approval in primary elections.

There are arguments to be made for using other PR methods, but it seems to me that SNTV is ideally suited to be a primary method, since it resists pushover and doesn't tend to overrepresent parties.

Using Approval as a base method, single non-transferable approval voting would look like
  • Advance Approval winner and Approval runner-up
  • Deweight to zero all ballots approving of AW.
  • Repeat until some threshold (e.g. 90%) of ballots have been used up:
    • Advance approval winner on the current remaining ballots
    • Deweight ballots approving of latest winner to zero
The advantages here are 
  • Relative simplicity -- No complicated reweighting algorithms, so each recount for the next approval winner is faster than the previous, and can even be done by hand.
  • Each winner (other than the first approval runner-up) will tend to be from a different party or faction of a party.  There may be some overlap from also advancing the overall Approval runner-up, but if the total AW and ARU are from the same party, it gives them an advantage under Approval to have a similar candidate for comparison. 
  • Most groups will be represented in the General election.
  • Pushover strategy is disincentivized by complete deweighting, so parties should not be threatened by strategic promotion of their worst candidate. There is some possibility that voters would do that regardless, but the effect should be no worse than in current top-two elections.
  • Modifications could include:
    • Stop advancing candidates when the highest approval on remaining ballots drops below a threshold. For example, if the total deweight threshold is 90%, if the latest winner has less than 5% approval on remaining ballots (half the complement of 90%), break the loop.
    • Stop when a certain number of candidates have advanced. For example, if using the 5% rule above, it is possible that 10 to 15 candidates could advance to the General, defeating the winnowing purpose of a primary. It seems reasonable to stop at 5 or 6 candidates.
    • Use a different method other than simple Approval.
I would be perfectly satisfied to have SNTAV as a primary method, but if one can handle a bit more complexity (say in smaller groups), it would be reasonable to use Approval Sorted Margins as the base method:

  • Use Ranked or Rated ballots with explicit Approval Cutoff. If not explicitly specified, cutoff is at zero-rating or last ranking.
  • Advance Approval Sorted Margins winner to general election 
  • Deweight to zero all ballots approving of AW.
  • Repeat until some threshold (e.g. 90%) of ballots have been used up:
    • Advance ASM winner on the current remaining ballots
    • Deweight ballots approving of latest winner to zero
For public elections, I think the SNTAV approach I outline above, with a 90% threshold, 5% minimum remaining approval, and limited to 6 candidates (4 approval winners and 1 top approval runner-up) gives enough room to enable more parties to develop.

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