single Transferrable Vote

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le pamei je muvyka'e se cuxna tadji

Single Transferrable Vote (STV) is a preferential, multiple-winner voting system. This is a version of it that follows the intent of the LLG bylaws - to elect between 3 and 6 people, as desired by the voters. It is described here in Lojban, then in English.

After some discussion, it was found that STV has properties that do not work for the LLG election. I've suggested a different method: Multiple-winner Condorcet.


i di'e tadji le nu so'imei prenu cu cuxna so'i jinga be lo nunturni

itu'e roda poi cuxna cu benji lo cuxna liste cei cuxste poi skicu leidu'u da zmanei makau makau du'o ledu'u da cusku vu'i leda se cuxna sepo'i leka da nelci ce'u (to mu'a le pamoi se cuxna cu pamoi fi leka da nelci ce'u toi) i go da na djica ledu'u de cuxna jinga gi ei de na cmima leda se cuxna porsi i la'edi'u skicu ledu'u da zmanei lenu nodi jinga le nunturni kei lenu de jinga le nunturni tu'u

ibabo le jinga korbi goi jyky cu du le cmarai mulna'u poi zmadu li ni'e ni ce'u cuxna fe'i ni'e zmarai ni cumki jinga

i le te cuxna cmima cei brodo cu cmima pa lu'a le'i jinga kuce le'i jivna kuce le'i toljinga i ro brodo cu jivna ca le nu cfari

i pruce fi lenu cuxna le'i jinga kei fo di'e

i pamai tu'e roda poi cuxna zo'u sruma ledu'u da cuxna le brodo poi jivna zi'e poi leda se cuxna porsi cu skicu ledu'u da traji nelci ke'a .i go noda jivna gi'e cmima leda cuxna porsi gi da cuxna node tu'u

i remai de poi brodo zo'u de su'ojyky.roi se cuxna ijo tu'e de jinga binxo ice'obo ko vimcu ro le su'ejyky.moi cuxste poi cuxna de ice'obo ko muvgau le cuxste poi na se vimcu vau ta'i lenu xruti ti poi pruce le pamoi ve pruce tu'u

i cimai no brodo cu su'ojyky.roi se cuxna ijo tu'e ko'a goi le brodo poi leni ce'u cuxna ke'a kei mecrai cu toljinga binxo ice'obo ko muvgau le cuxste poi cuxna ko'a vau ta'i lenu xruti ti poi pruce le pamoi ve pruce tu'u

i vomai go li ni'e ni jinga su'i ni'e ni jivna kei ca du le me'anrai ni cumki jinga gi ro jivna cu jinga binxo

i mumai go ro brodo ca jinga jo toljinga gi fanmo le cuxna tadji


In English:

Each voter submits a ballot that gives his preferences among the candidates - his first choice is indicated, then his second choice, and so on. If a voter thinks a certain candidate should not be elected, he should not rank that candidate at all. This indicates that he would rather have nobody filling a slot than that candidate getting elected.

A winning threshold is determined as follows: divide the number of voters by the maximum number of slots to fill, and take the lowest integer larger than this number. The ballots are arranged in some random order.

The candidates will be in three sets: winners, losers, and contenders. Every candidate begins as a contender.

The following steps are used to determine the winners:

1. Each voter is assumed to cast a vote for the highest-ranking candidate on his ballot who is a contender. If none of the ranked candidates are still contenders, his vote goes to nobody.

2. If a candidate receives a number of votes greater than or equal to the winning threshold, this candidate becomes a winner. The first N votes, where N is the winning threshold, for this candidate are set aside - they were used to elect the candidate. The remaining votes are redistributed by returning to step 1.

3. If no candidate receives the threshold number of votes, then the candidate with the fewest votes becomes a loser. His votes are redistributed by returning to step 1.

4. If the number of winners plus the number of contenders is currently equal to the minimum number of slots to fill, then all contenders become winners.

5. If every candidate is either a winner or a loser, the election is over.


While deciding beforehand how the election is to be conducted would save a lot of time -- especially for an irc meeting, which already lengthened by the mechanics of the thing, using ever more complex voting devices seems counterproductive. I have not seen the results of the latest election yet, but abstractly I don't see why the results could not have been achieved by an ordinary election. Given 23 voters (I think it was, adjust as the facts require), anyone with 12 or more votes is elected. If this elects too many or too few, then use order by number of votes to cut off or extend. Notice that after some number (three?), more members need not be elected, so that problems with ties can almost always be resolved (barring a five-way tie for third place). pc

  • That is, in fact, the system we used. People are already complaining on the llg-members list that this system leaves no way to express that you prefer some candidates to others without voting against the others. The remedies I've heard proposed are more complicated for the voter than STV, which is only complicated for the vote-counter. rab.spir
    • I'm glad that that is what ended up being used; the discussion did not sound like it -- though that may have been a product of opaque exposition (which certainly occurred). As for preferences, I don't exactly see what that has to do with the issue. It is rarely a factor in elections beyond the 0,1 choice. My experience with various kinds of preferential ballots (rank orderings, say)has been that they usually end up either with the same group that would have come by an ordinary election or with only the unobjectionable folk getting elected -- everybody's middle choice. These may be good things, of course, but hardly worth the extra work involved.
      • The objection is this. Given candidates A and B, the current system allows you to give preference to A over B (by voting A and not voting B) or to give preference to A or B over a vacant slot (by voting for both A and B). It does not allow you to express your preference for A and at the same time your preference for B over a vacant slot. The result was in fact an open slot in the board of directors, even though I'm sure that either of both candidates eliminated would have been acceptable for a majority of the membership. xorxes
        • Again, this is not obviously something that a vote needs to say, but, assuming that "X is better than nothing" (and presumably "Better nothing than X")is something we want to say, we can simply add the multi-office analog of "None of the above," a Null candidate, for whom we can vote when we run out of people we could abide on the board. I'm not sure what Null winning the election hands down would do officially, but it does suggest that the nomination process needs some work (or that the organization is in a rather bad way). pc

I assume that in step 2, when you say N votes are set aside, you mean that you set aside N ballots that include N votes for the winner, right? (Otherwise I don't see the point of arranging the ballots in some random order.) Do you know why this is preferred to just keep using all the ballots for the next round, so the result does not rely on chance? Does it have to do with protecting minorities? I'm thinking of this situation:

Voter: 1 2 3 4 5 6 7 8 9 10 11 12

1st vote A A A A A A A A A E E E

2nd vote B B B B B B B B B F F F

3rd vote C C C C C C C C C G G G

4th vote D D D D D D D D D H H H

Suppose 4 people have to be elected. Our current system will elect A, B, C, and D, as they all have a majority of people voting for them. STV will elect A, B, E and C. Modified STV, without discarding ballots, will also elect A, B, C, D like the current system. xorxes

  • That's the reason. I forgot about how strongly proportional representation was built into STV, in that it can elect a candidate who is strongly supported by a minority and unacceptable to the majority. That's not what we're looking for, so STV doesn't actually work. rab.spir