Dual Member PLACE

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This page describes Dual Member PLACE, a nonpartisan version of PLACE voting. This can easily be generalized to "three member PLACE" (with one district for every 3 seats), "4 member PLACE", etc.

PLACE voting: process (how)

Explain the basics of Dual Member PLACE voting (the elevator pitch)

Here are the important points:

  • There is one district for every two seats. If there is an odd number of seats, round the number of districts up.
  • Voters can vote for any candidate in any district, though ballot design encourages most voters to vote in their own district.

For most voters, a local candidate will be the best option. But there are also some voters who identify with a community defined by something besides geography, whether it be ethnicity, some specific political issue, age, etc. The best way to represent such voters is to give them the widest possible choice.

  • After ballots are tallied, each candidate's votes are given a transfer order, which is that candidate's predeclared allies, from most to least popular.

Transfer orders are used when a candidate is eliminated, and also, if she (he) gets more than half an average district's worth of votes, for the extra fraction of each of her votes above that total. Votes retain their original transfer order as they pass from one candidate to another.

Why are transfer orders based on a combination of ballot tallies ("most to least popular") and each candidate's predeclared allies? Because that enables a simple ballot where the voter has the broadest possible choice, of all candidates electionwide/statewide, without burdening voters with making rankings (that may not end up mattering) of every single one of those candidates.

  • In each district, the candidate with the most votes is elected. If they have more than a quota (half an average district worth) of votes, the excess is transferred. These candidates are responsible for representing the local interests of their district.
  • Whenever a candidate accumulates a quota (average-half-district worth) of votes, they are elected at large. If they have more than a quota of votes, the excess is transferred.
  • Candidates are eliminated, and their votes are transferred, until there's one winner per district. Whenever there are no more unelected candidates with a quota, the candidate with the fewest votes is eliminated.

How does PLACE voting work? (Details)

Assuming that there is one equal-population district (aka riding or constituency) per seat, and that the parties have already nominated candidates by district, PLACE has 3 basic steps:

  1. Before the election, candidates designate their "allies".
  2. For the election, voters each pick their favorite candidate, and winners are chosen as explained below.

Step 2, where the winners are actually chosen, has three sub-parts:

2.1 Voters choose their favorite candidate. The ballot lists the candidates running locally. There is also some way to vote for any candidate in another district — perhaps as a write-in, or perhaps using an extended ballot which lists all candidates, or perhaps nearby candidates are listed while far-off ones must be written in.
2.2 Ballots are tallied and each vote is converted to a transfer order: their predeclared allies, from highest to lowest direct vote total. If these run out, a ballot is exhausted. Votes are never transferred to candidates who have been eliminated or who have already accumulated a full average district worth of votes.
2.3 Votes are transferred until only one winner remains per district.

Of the three steps directly above, voters only have to worry about step 2.1. They can leave the details of step 2.3, the transfer process, to the experts. Though those details are a bit more technical, they are basically STV (Single Transferable Voting), a well-known proportional representation method.

2.3.1 A "quota" is defined as half the average number of votes per district. (Note: in voting theory, this is known as the "Hare quota" if there are an even number of seats, and the "Droop quota" if there are an odd number of seats).
2.3.2 If a candidate ever has more than a full quota of votes, the fraction of each of their votes above that is transferred. For instance, if one candidate got two quotas of votes, then half of each of those votes would be used up and the other half would be transferred as "excess". Thus, transfers can involve partial votes.
2.3.3 A candidate X can be eliminated when they have the fewest votes of any remaining (unelected and uneliminated) candidate. This rule applies whenever there are no more candidates to elect for reason 2.3.2, and will typically apply multiple times before all seats are filled.

Thus votes will move from weaker candidates to stronger ones until they make up full quotas and the seats fill up.