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Tom Monto

Teaching STV - the first STV election for a union or other group

Updated: Dec 21, 2023

Say a union meeting needs to elect a board of officials (say ten council members) and wants to have each part of the union represented on the council


STV is chosen to be the method of election, and an expert is brought in to pull it off.


Pressed for time, the expert has just a few moments to explain how STV works and prepare the delegates to cast their vote.


might start by saying something like this --


the point of voting is to have due representation of the range of sentiment among the voters.

STV can do that.

No one group will be able to take all the ten seats.

Instead the council that we will elect will be a mixture, balanced in rough proportion to the various sentiment among the voters.

We will have proportional representation.


You say parties are not used and that is fine.

Parties actually play no part in STV - votes are cast for candidates. The fairness is produced by a high proportion of votes actually used to elect someone and each person being elected by the same number of votes as much as possible.



This is done by the

- election of ten members in one contest - there is a lot of choice among the candidates who will come forward and ten of them will be elected.

- each voter will have one vote.

- The vote may be transferred to another candidate if the vote would otherwise be wasted.

the rankings act as instructions for election officials -- if the vote would otherwise be wasted, please move it according to the marked preferences.


(following group involvement exercise can be dispensed with if pressed for time.)

We can do small group involvement exercise.

say we need to choose three types of food to serve at a picnic.

here's signs for the choices

Chicken hamburger fish vegetarian casserole tossed salad chocolate cake chocolate cookies turkey potatochips.

20 to 23 people volunteer to participate

any food with six votes will be served.

Vote for the food you like by standing near the sign.

Each person can only vote for one.

A food must have at least six votes or it will not be chosen.

[flurry of people grouping with their choice but then leaving it if the food has six already or it does not have six votes. Finally three foods have six or more voters standing next to the sign.]

So we see variety of foods chosen - not just meat and not just chocolate cake.


How many (of the active volunteers or the audience as a whole) like at least one of the foods picked?

How many like two of them?

How many like all three?

That level of satisfaction is produced by fair voting under STV.


of the 20 participants, how many did not elect a food?

We saw people leaving a candidate if that candidate would be elected without that vote, and we see voters who initially supported an un-electable candidate move to help elect a food that the voter also prefers.


We cannot run around like that in a real election - plus it is not secret voting --

so that is why STV has ranked ballots.


To recap, the election will be held using STV. This is done by the

- election of ten members in one contest - there is a lot of choice among the candidates who will come forward and ten of them will be elected.

- each voter will have one vote.

- The vote may be transferred to another candidate if the vote would otherwise be wasted. When transferred, the vote is moved to help the candidate that the voter has marked on the ballot as his or her next preference.

If the vote is placed on someone who is un-electable, the vote will be transferred if possible.

If the candidate marked as the first preference is elected, and has more votes than are necessary, the back-up preference marked on the vote will be used to formulate a transfer of surplus votes.


To make these transfers possible, each voter will mark back-up preferences.

These are to be used if the candidate marked as the first preference is found to be un-electable.

Or if the candidate is elected, the back-up preference is used to set the transfer of surplus votes.


Any candidate who is eliminated or elected receives no further vote transfers. If the next choice on a ballot being transferred is a candidate already out of the running, that preference will be passed over and the ballot will be transferred to the next usable preference.


so that is it in a nutshell - single transferable voting where multiple members are elected.


Voter will mark 1 beside the first choice, 2 beside the second choice and so on.


The votes will be collected and looking just at the number 1 preferences on each vote, the vote official will determine the number of votes for each candidate.


Quota, the number of votes that ensures election, will be derived.


If not all the seats are filled by quota in the first count, the first count is followed by a series of counts or stages where votes will be transferred as necessary. The counting will continue until the vote count process has filled the ten seats by the right number of candidates passing quota or by eliminating all but the right number of candidates. Usually it is done by combination of both of those methods.


In the first count, the candidates in the winning positions (the top ten spots) will belong to different groups. The process of vote transfers will not affect most of them.


Most of those top ten in the first count will be elected.

but perhaps one or two might lose their leading position due to vote transfers and then someone else with more general support will be elected. The changes effected by vote transfers ensure more fairness by reducing waste - either surplus votes cast for an overly-popular candidate or votes wasted on candidates who are un-electable.


The transfers may change the leading candidates to ensure that each voting block gets its due share of seats in more proportional ratios than the initial count.


Transfers of surplus votes will be conducfed using the relatively-simple whole-vote method, with attention paid just to the next usable marked preference. For a hundred years it has been used in national elections in Ireland and Malta.


The transfers will be announced as they happen (or reported at the end to show how they happened.)


So the first step is to mark your ballot with your preferences:

Mark as few or as many candidates as you like.


The voter is encouraged to mark at least four back-up preferences.

Back-up preferences are never used if the first-preference candidate is still in the running.

The voter cannot hurt the chances of the most-preferred candidate by marking a back-up preference.

Back-up preferences will be used if necessary so that the vote is used to elect someone preferred by the voter.

The back-up prefence will be used only if necessary to allow the vote to be used when it might otherwise be wasted.


The ranking on the ballot serves two purposes - you show how you feel about the candidates you like and how you feel about the candidates you do not like.

You should give 1 and the other low numbers to those you like, give high numbers to those you dislike, and sprinkle the in-between numbers among the others.

But give only one number to each candidate and don't give the same candidate more than one number.


say 16 candidates are in the running

numbers 1 to 16 would be used. 1 being most liked


in lieu of printed ballots, write the names of your preferred candidate on the ballot. The name at the top is the first choice, the next down is the second preferred candidate, etc.


======================================================


Detail on the vote count if people want to know

Transfers are conducted in this manner.

In the first count, the total valid votes is determined.


The quota is determined.

(math: number of valid votes/11, plus 1)


The quota is the amount that immediately elects the candidate. It also determines the number of votes that remain with the elected candidate -- anything more than that is surplus.


The vote proceeds in different counts or stages.

In each count, either surplus votes of a previously-elected candidate are transferred or the least-popular candidate is eliminated and the votes transferred.

In each situation the vote is transferred according to the marked preference marked by the voter, if possible.


Transfers of surplus votes will be conducfed using the relatively-simple whole-vote method, with attention paid just to the next usable marked preference.


So say one candidate exceeds quota.

How many votes are surplus?

If they are numerous enough to be significant, the surplus votes should be transferred in the next count. That will prevent the votes from being wasted with bad effect on proportionality of representation.

(see below for more on transfers of surplus votes)


If in a count there are not surplus votes numerous enough to be transferred, then in the next count eliminate the least-popular candidate.

This kind of transfer is simpler -- simply look at each vote and move it to the next usable marked preference, if any. Keep track of how many are transferred.


By the end of the vote transfer process, STV will have filled the ten seats by the right number of candidates passing quota or by eliminating all but the right number of candidates. Usually it is done by combination of both of those methods.


============================================

Back in 1872 Walter Baily of England described the working of STV in his book PR in Large Constituencies:

by transferring surplus votes from candidates who have quota to others and from those who are un-electable to others still in the running, you eventually fill the seats either by the right number attaining quota or "by all but the right number having been withdrawn" (eliminated).


Each large group will benefit from transfers so that as many candidate representing the group pass quota.

Each small group will either win one seat or those votes will be transferred to assist one of the larger group that shares their sentiment.

Voter has liberty to mark preferences for any of the candidates. You are not required to follow a list. voter can mark their own.

The vote can only be transferred if it bears a back-up preference marked for a candidate who is not already elected or already eliminated.


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More on transfers of surplus votes

If the surplus is more than the difference between the bottom two candidates among the other candidates, a transfer has to be tried.

Looking at the candidate's votes, put the votes into piles based on the second marked choice.

Any votes without a second preference marked, are put in a separate pile. These will remain with the successful candidate.


If the "exhausted vote" pile is more than the quota, just simply move the remaining votes to the next preference marked on each one. Keep track of how many are transferred.


if the pile of exhausted votes is fewer than quota, then the number of votes able to be transferred are more numerous than the surplus.

In that case the transferable votes must be reduced mathematically to the number of surplus votes.


Count each pile and then calculate how many votes in each pile should be transferred.


(math:

To calculate the number of votes belonging to elected candidate A that should go to candidate B:

B/T X S = b

where B is number of votes held by A that are next marked for candidate B

T is total number of votes held by A that bear usable next marked preference

S is number of surplus votes held by A

b is number of votes to be transferred to B.)


Various methods can be used to conduct transfers of surplus votes. Some are more random than the method described above, others are less random.

The whole-vote method described above is not random at all as regards the next marked preference, but lower preferences piggybacked along with the transfer may be used later and due to being randomly selected, there is chance that they might be skewed to a degree that might effect later transfers. On the other hand, the votes transferred might never be transferred again so those piggybacked lower preferences might never be used at all.


The transfer of surplus votes are the most complicated of the transfers. But they are few in number.

In an election of ten council members, there will never be more than nine of those mathematical transfers at the most.

Surplus votes of the last elected member will never be transferred because the process ends when the last seat is filled.

Some members might be elected at the end when the number of remaining candidates drops to the number of remaining open seats. They likely do not have quota so likely have no surplus of votes. And anyways their election marks the end of the process because all the seats are filled. So no transfer occurs in these cases.

As well, some members might be elected with too few surplus votes to make transfer necessary;

Other elected candidates may have fewer transferable votes than the surplus so transfers can be done without complicated math.


Most of the transfers are transfers from elimination of a candidate. All of them and some of the transfers arising from the election of a candidate are conducted just by looking at the next usable marked preference on the vote.

Very simple and straightforward.


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