Block approval voting
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Block approval voting (also called unlimited voting, in reference to limited voting) is a winner-take-all system where each voter either approves or disapproves of each candidate, and the k candidates with the most approval votes win (where k is the predetermined committee size).[1][2] It does not provide proportional representation.[2]
Example with comparison
[edit]Candidates are running in a 3 member district of the 10000 voters. Voters may not cast more than one vote for a single candidate.
- Under block approval voting (unlimited voting) voter may vote for any number of candidates.
- Under limited block approval voting voters may cast 6 votes maximum (twice as many as there are winners).
- Under (plurality) block voting, voters may cast 3 votes (but do not have to).
- Under the single non-transferable vote, voters may cast 1 vote.
Party A has about 35% support among the electorate (with one particularly well-like candidate), Party B around 25% (with two well-like candidates) and the remaining voters primarily support independent candidates, but mostly lean towards party B if they have to choose between the two parties. All voters vote sincerely, there is no tactical voting.
| Candidate | Party | Block approval voting | Plurality block voting | Single non-transferable vote | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Votes | % | Elected? | Votes | % | Elected? | Votes | % | Elected? | ||||||
| Candidate A1 | Party A | 4200 | 42% | 8. | 3555 | 36% | 3. | 
|
800 | 8% | 4. | |||
| Candidate A2 | Party A | 4500 | 45% | 5. | 3700 | 37% | 1. |
|
1900 | 19% | 1. |
| ||
| Candidate A3 | Party A | 3900 | 39% | 9. | 3600 | 36% | 2. |
|
700 | 7% | 9. | |||
| Candidate B1 | Party B | 5200 | 52% | 1. |
|
2600 | 26% | 4. | 900 | 9% | 3. |
| ||
| Candidate B2 | Party B | 5000 | 50% | 2. |
|
2500 | 25% | 5. | 1100 | 11% | 2. |
| ||
| Candidate B3 | Party B | 4700 | 47% | 4. | 2400 | 24% | 6. | 400 | 4% | 12. | ||||
| Candidate I1 | Independent | 4400 | 44% | 6. | 2300 | 23% | 8. | 800 | 8% | 4. | ||||
| Candidate I2 | Independent | 4900 | 49% | 3. |
|
2395 | 20% | 7. | 800 | 8% | 4. | |||
| Candidate I3 | Independent | 4400 | 44% | 6. | 1900 | 19% | 9. | 700 | 7% | 7. | ||||
| Candidate I4 | Independent | 3900 | 39% | 9. | 1800 | 15% | 10 | 700 | 7% | 7. | ||||
| Candidate I5 | Independent | 2600 | 26% | 11. | 650 | 7% | 11. | 600 | 6% | 10. | ||||
| Candidate I6 | Independent | 2300 | 23% | 12. | 600 | 6% | 12. | 500 | 5% | 11. | ||||
- Under the single non-transferable vote (not a type of approval voting), the 3 most popular candidates according to voters first preferences are elected, regardless of party affiliation.
- Under (plurality) block voting, the party with plurality support most likely wins all seats.
- Under limited block approval voting voters, voters of independent candidates may use their extra votes to help candidates other than their top 3, which may result in the reversal of the plurality block vote result.
- Under block approval voting, any party-affiliated or independent candidates particularly popular among the population may be elected, but it is possible that about half of the population can elect no representatives.
References
[edit]- ^ Fishburn, Peter C.; Little, John D. C. (May 1988). "An Experiment in Approval Voting". Management Science. 34 (5): 555–568. doi:10.1287/mnsc.34.5.555. ISSN 0025-1909.
- ^ a b Lackner, Martin; Skowron, Piotr (2023). Multi-Winner Voting with Approval Preferences. Springer Nature. ISBN 978-3-031-09016-5.