Range voting encourages honesty (executive summary)

  1. Theorem: In essentially every voting system based on rank-order ballots, there is always a 3-candidate election situation (example) where casting a vote that dishonestly says A>B when you honestly feel B>A, is strategically better than casting an honest vote.
  2. Contrasting Theorem: But in range voting, that never happens – being dishonest in this way never pays in 3-candidate elections.
  3. Another theorem: In range voting, it also never pays to "betray your favorite" by giving him anything other than the top score. (Sounds simple, but this unfortunately is not true in many other voting systems, including plurality and IRV.)
  4. So range voting encourages honesty in 3-candidate elections better than every system based on rank-order ballots.
  5. Experimental fact: In the USA's 2000 presidential election, voters who thought Nader best were urged not to be strategically stupid and instead to vote (dishonestly) for either Gore or Bush, and polls showed that about 90% of the voters who thought Nader was best in fact did vote for somebody else. [Another, different sort, of example – from p.65 of Lakeman & Lambert's book: a 1950 Gallup poll showed 38% of British voters wanted to vote Liberal but only 9% did.]
  6. Experimental fact: In the USA's 2004 presidential election, about 3/4 of range voters (in a range voting exit poll of random voters) chose to vote in a style which did not award the max (99), min (0), or X (intentional blank) score to every candidate. In other words the fraction of range voters who choose to sacrifice some strategic oomph in order to be more honest, experimentally is enormous.
  7. The consequences of greater voter honesty are huge – check out the enormous experimental differences between the vote totals for the third-party candidates under range, versus under approval and plurality voting.
  8. When the voters do choose to vote strategically in range voting, the consequences are mild, even pleasant: Maximizes "pleasant surprise", Victory for the (honest voter) "beats-all winner". (Try to find another voting system with such pleasant provable properties under strategic voting, I dare you.)
  9. There is a good reason to believe that range voters will be both honest and strategic (both in large fractions) as far as the eye can see 100 years into the future with range voting. A 50-50 mix is probably a good rule of thumb.

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