Thursday, February 4, 2010

Oscar Update

As we discussed last summer, the Oscar for best picture is moving from a field of 5 to a field of 10, and the vote is done by instant runoff. Here's the 2009 best picture nominees, vs. IMDB's "Top Rated Titles".

AcademyIMDB
  • Avatar
  • The Blind Side
  • District 9
  • An Education
  • The Hurt Locker
  • Inglorious Basterds
  • Precious: Based on the Novel ‘Push’ by Sapphire
  • A Serious Man
  • Up
  • Up in the Air
  1. Avatar
  2. Up
  3. Inglorious Basterds
  4. District 9
  5. Fantastic Mr. Fox
  6. Star Trek

The IMDB list is a little truncated, since they only list by decade, and only the top 50 of the decade, so its hard to find IMDB's best 10 films for any one year (maybe they don't want to step on the Academy's toes). You'll note, there's a good amount of overlap this year, which isn't too surprising since the nomination step uses a "name five" approval-style ballot, in which each voter names up to five films, without ranking them. The ten most-often-named films become the nominees. Top-5 is mathematically similar to IMDB's score-based voting system; at least, the two are more similar to each other than either is to the instant runoff voting (IRV) used for the final round.

But which picture will win? It's tempting to say Avatar, since it's IMDB's top rated film of the year, but we know that IRV has somewhere between a 5 and 15% chance to exhibit non-monotonic behavior, in which the true first-choice is eliminated before the final round. And that's with three strong contenders; the odds get worse the more there are, and I think at least four of these can be considered "strong contenders".

But what does "true first-choice" mean? For me, it means consensus. If you put all the Academy voters in a room and told them to watch a movie, which movie would engender the greatest total happiness for the crowd? That's the question that score voting (and IMDB) asks. But supporters of IRV instead speak of something they call "core support"; they say that it's most important for a winner to have a large following of fanatics, voters who like them best of all. They don't use the word "fanatic", but it's appropriate. Instant runoff repeatedly removes the choice with the fewest fanatic followers and shuffles them off to their next favorite group; it's fair to call them fanatics because other options that you may also like are never considered until your number-one is eliminated. In other words, IRV doesn't offer you much of an opportunity to offer a compromise, because its almost always the compromise that gets eliminated by non-monotonic behavior. So the question is, is Avatar a compromise? Does it make everyone mostly happy, or does it make only a few people very happy? Luckily, IMDB records that data too! Maybe we'll examine that next time.

Also, remember that the Academy hates science fiction, and animation. In which case, maybe Inglorious Basterds has a good chance...

3 comments:

  1. Huh? You want a "compromise choice" who might be no one's first choice and only can win if Academy voter hurt their first choice by indicating support for others? That flies against Academy history of what it wants -- a film that at least some members are passionate about.

    Preferential voting is a good compromise between plurality and other systems that make one's first choice little more important than one's second choice.

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  2. Yes. I would want a compromise who might be no one's first choice. But it might also be no one's last choice; that's the essence of compromise.

    But this idea of "hurting your first choice" is precisely what I'm referring to when I say IRV empowers fanaticism. And fanaticism is what drives "us-versus-them" partisanship, precisely because it blinds you to compromise. It plays right into the "lesser of two evils" strategy, which is the reason that IRV tends to have the same bad outcomes as plurality voting.

    Submitting to compromise isn't weakness; it's the right way to do democracy. But since IRV only looks at one entry on each ballot at a time, it cannot find a compromise, just like plurality. Furthermore, I don't care if "my first choice" is hurt by my ballot, I care if I am hurt, and with IRV's inability to acknowledge my compromise options throughout the tallying process, I am more likely to end up with my least preferred outcome.

    This is all, perhaps, less important when it comes to movies. After all, it's just some silly statue, and it's not like Hollywood has two well-defined factions that year after year support the same kinds of movies, which would tend to multiply the negative effects of IRV. But I'm not worried about Hollywood, I'm worried about Washington D.C., and every town hall in every city across the country.

    Now, your last paragraph is, I'm afraid, complete gibberish.

    IRV and preferential voting are not synonyms. Preferential voting can also refer to Condorcet methods, Borda count, cumulative voting, and a dozen more; and I don't know what you're referring to when you attack "systems that makes one's first choice little more important that one's second choice," since all preferential systems are impacted differently by the relative ranking of choices within them; so it sounds like you're saying "A is a good compromise between B and the worst examples of A."

    Meanwhile, approval voting and score voting (which are what I'm advocating for) don't even have explicit ranked choices, which makes your statement seem rather nonsensical when applied to them.

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  3. For anyone looking to maybe make a little money applying what I wrote in this poist, District 9, Up, and Inglorious Basterds are all underpriced on intrade.com; and/or The Hurt Locker is overpriced. Assuming movie-people think like internet-people, of course.

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