VFA Runoff

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VFA Runoff or VFAR is a type of two-round runoff voting, but using the Vote For and Against ballot in the first round of voting. If a candidate receives more than half of the against votes in the first round, this candidate is barred from the second round. Other than this, the two candidates with the most for votes advance to the second round, which uses a simple "vote for one" ballot.

In a first-round scenario such as:

 49 voters vote for A, against C
 24 voters vote for B, against A
 27 voters vote for C, against A

Standard VFA will elect C outright, while VFA Runoff will hold a second round between B and C. This way, the A supporters have the ability to transfer their support.

Example

Tennessee's four cities are spread throughout the state

Imagine that Tennessee is having an election on the location of its capital. The population of Tennessee is concentrated around its four major cities, which are spread throughout the state. For this example, suppose that the entire electorate lives in these four cities, and that everyone wants to live as near the capital as possible.

The candidates for the capital are:

  • Memphis on Wikipedia, the state's largest city, with 42% of the voters, but located far from the other cities
  • Nashville on Wikipedia, with 26% of the voters, near the center of Tennessee
  • Knoxville on Wikipedia, with 17% of the voters
  • Chattanooga on Wikipedia, with 15% of the voters

The preferences of the voters would be divided like this:

42% of voters
(close to Memphis)
26% of voters
(close to Nashville)
15% of voters
(close to Chattanooga)
17% of voters
(close to Knoxville)
  1. Memphis
  2. Nashville
  3. Chattanooga
  4. Knoxville
  1. Nashville
  2. Chattanooga
  3. Knoxville
  4. Memphis
  1. Chattanooga
  2. Knoxville
  3. Nashville
  4. Memphis
  1. Knoxville
  2. Chattanooga
  3. Nashville
  4. Memphis

Assume that in the first round, voters vote for their top preference and against their last preference.

Memphis is disqualified from advancing due to receiving more than half of the against votes. So unlike a standard two-round, top-two runoff, the second round is between Nashville and Knoxville rather than Memphis and Nashville.

In the second round, Nashville defeats Knoxville 68% to 32%.

Instant VFA Runoff

In the above scenario IRV elects Knoxville. An "instant" version of VFA Runoff could be defined like this:

The voter ranks the candidates. For simplicity say that rankings must be complete. While more than one candidate remains, eliminate one: If more than half of the voters rank the same candidate strictly last among all remaining candidates, eliminate this candidate; otherwise eliminate the candidate with the fewest first preferences as under IRV.

In the above scenario, "instant" VFA Runoff would eliminate Memphis as before. At that point more than half of the voters rank Knoxville last, so that Knoxville is eliminated. At that point, this same majority ranks Chattanooga last, so that the winner of the method is Nashville, the Condorcet winner.