Explicit approval voting



Explicit approval voting refers approval voting elections where the ballots allow for abstentions. To allow for this, an option is provided to explicitly state disapproval. So, the ballot will list Approve and Disapprove for each candidate (and may also have a Neutral option). Leaving a candidate without without "Approve" or "Disapprove" implies "Neutral" (and implies abstaining from voting). It is important to note, however, that this is not an example of Score Voting because it does not determine a winner by a simple sum of score values.

Quorum
By itself, this rule leads to the possibility of an unknown dark horse candidate winning with only a few approve votes and many abstentions. This can be prevented through the use of various quorum rules, but hasn't seemed to be a problem in actual elections, despite abstention being common.

Comparison
While Explicit Approval and Combined Approval have equivalent ballots, they are not tallied the same. For example, if Candidate A received 5 Approvals and 5 Abstentions, while Candidate B received 9 Approvals and 1 Disapproval:


 * Under Explicit Approval, Candidate A would win, with 5/(5+0) = 100% support, vs Candidate B's 9/(9+1) = 90% support.
 * Under Combined Approval, Candidate B would win, with 9-1 = 8 points vs Candidate A's 5+0 = 5 points.

Usage
Wikimedia and Wikipedia elections are held using an equivalent system, in which voters must choose Support, Oppose, or Neutral for every candidate.

Ballot initiatives and judicial retention elections are similar to Explicit Approval, in that voters may vote Yes, No, or abstain on each option, and they are passed/retained if the Y/(Y+N) ratio is greater than 50%. There is sometimes a quorum participation rule. For example, in Nebraska, a ballot initiative must receive Yes or No votes from at least 35% of those who cast ballots in the general election (less than 65% abstention) to be valid.

Wikimedia elections
Many Wikimedia and Wikipedia elections using a form of explicit approval voting, where the winner is the candidate who has the highest approval among those who didn't abstain: A/(A+D) In these Wikimedia elections, the voters were asked to choose "Support", "Oppose", or "Neutral" for every candidate. The winner is the candidate with the highest support percentage: the highest proportion of Support votes out of combined Support and Oppose votes = S/(S+O). Wikimedia's system is not equivalent to 2-level Score voting (where the levels are "0" and "1"). Wikimedia's variant is equivalent to 3-level Score voting where voters may explicitly abstain, and the default choice is to abstain. The levels in Wikimedia's system are (−1, 0, +1) rather than (0, 1), so they may be affected by the psychological consequences of disapproval voting.

Results
The Wikimedia Foundation has used this method for Board of Trustees and Funds Dissemination Committee elections in 2013, 2015, and 2017, after previously using Approval voting and Schulze method.

If tallied using Score voting rules ("combined approval voting", where O=−1, N=0, S=+1), the 2015 Wikimedia Board election would have had a different winner, with the candidate in 4th place moving up to 2nd. The 2017 Board and 2015 FDC elections would have had a different top-3 order, but the same 3 candidates would have won.

In all 8 elections from 2013-2017, the most common vote was Neutral, which was cast about twice as often as Support, which in turn was cast about twice as often as Oppose. Winners typically receive 70–85% support.

It has also been used for Steward elections since 2009 or earlier, with the current rules electing all candidates that receive at least 30 votes in favor and at least 80% support.

Wikipedia uses this in a non-binding way for Administrator nominations, etc.