AB/STV experiment

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This page is here to fine-tune the STV voting proposal project to the AC representative for the next three elections

An Election Experiment

The W3C Team is experimentally using alternative voting system to help determine whether the outcome of elections would change if we used a different voting system, and whether this might make election outcomes more broadly representative of voters' preferences.

This experiment will be conducted over the next three rounds of elections (AB or TAG) when there is more than one seat to fill.

Balloting

Voters will have two ways to vote during the ballot; to support the experiment, both need to be completed.

1. Voter selects from the running candidates, up to the number of seats available, with no ranking. This is the official vote.

2. Voter ranks as few or as many candidates he wants in preference order. This is the experimental vote used to analyse the alternative voting system.

In the experimental vote, '1' indicates the most preferred candidate. Giving two or more candidates an equal rank is valid.

If a voter wishes to explicitly not support candidates, they can rank the option "no (other) candidate" lowest, leaving the unsupported candidates unranked. If the voter does not rank all the candidates and does not use "no (other) candidate", the W3C ballot management system will consider implicitly that the voter stated "Any of the other candidates" after the last one he ranked.

Example of a ballot for 3 seats with 6 candidates

Candidate names : Alice, Byron, Charlie, Daniels, Elliott, Franklin

Current system vote : Byron, Elliott

Experimental system vote : (1) Elliott, (2) Byron, (3) Alice, (4) Charlie (5) no (other) candidate


Use of Experimental Data

The results of this experiment will be used by W3C team to emulate ballot results, based on 3 calculations : (1) if vote would have voted only for one candidate (the first one). (2) if vote was using Single Transferable Vote [1]. (3) is vote was using Single Transferable Vote Schulze method [2] STV method is a ranking method used when several candidates are running for an election, with multiple open seats. It allows to find the best combination of winning candidates, taking into account the ranked preferences of the voters. Several flavors of SVT are existing, either simple, or Schulze, the last one allowing to better countermeasure tactical votes.

The results of that experimental voting will not be used to influence the actual ballot. The W3C team will decide to communicate to the AB and AC the experiment's results.

Other potential details to expose (to be completed)

- using the no more candidate : how does that influence the calculation ?

- drafting key factors to decide to switch from traditional to SVT


References

[1] STV on wikipedia [1]

[2] Schulze STV on wikipedia [2]

[3] approval voting on wikipedia [3]

[4] Single Non transferable Vote on wikipedia [4]