Wednesday, July 8, 2009

Award Season

I've been trying to come up with some sort of clear conclusion to draw about the Academy Awards vs. IMDB's Top 250, but I keep running into the problem that I don't know half the movies on both lists, and when I try to generalize anything from conclusions based on what I do know, I run into this wall of uncertainty (another reason that I was hoping for comments, but oh well.) But, before I give it all a rest, I'd like to talk about another award-slash-voting-system: science fiction's Hugo Awards.

According to their description, the Hugo Awards (like the Academy Awards) uses a two-step process; nominations and final voting. The nomination process for the Hugo's uses approval voting (good on them!) but with a limit of five titles on each persons ballot (oh well, no one's perfect) with the top five being nominated. The final voting step is instant-runoff (uh oh!) with one important exception.

In addition to the nominees, Hugo voters are allowed to rank "no award" anywhere on their ballot. After determining the IRV winner by the normal method, the potential winner is compared pairwise to "no award" (obviously, if "no award" was the IRV winner, there is no award). In other words, for each ballot it is determined whether that ballot ranks the potential winner higher or "no award" higher, irrespective of the rankings of all other nominees. If more ballots prefer "no award" than prefer the potential winner, then there is no award.

This "special case" highlights one of the more damning aspects of instant runoff: it does not, despite its advocate's claims, always pick a majority-preferred candidate, but rather, sometimes, one of the other candidates is preferred over the "winner" by a majority of voters. (This, among other issues, happened in Burlington, Vermont's most recent mayoral election.)

These sorts of pairwise comparissons—looking at a more-than-two way race as a series of one-on-one contests—is the heart of another ranked-order voting method (or rather, a family of such methods) called Condorcet's method; and as ranked-order methods go, based on Bayesian regret, Condorcet is better than IRV (not a tall order since IRV is the second-worst method, only ahead of plurality). If the Hugo awards are so fearful of "no award" getting an unfair pairwise chance against the IRV winner, I wonder why they don't use an entirely pairwise method; surely there must be some overlap with judges of a science-fiction contest (geeks) and open-source programmers (more geeks), and the programmers use Condorcet for their elections.

Of course, I recommend that both of them move to score voting; however, the approval-based nomination step is a great idea for the initial round of a two-step process (although on average the approval votes alone would likely get a better result than the final IRV round, barring the fact that the two-round process gives everyone a chance to go read any nominees they missed before the decisive round.)

Finally: I try to keep my personal views on any actual issues out of my writing here, and focus only on the process by which groups can make more-democratic decisions. But if Anathem doesn't win Best Novel, I will riot in the streets.

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