Scoring Rules (2012)

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This is an explanation of why the particular scoring rules for 2012 have been adopted. The problems we had with last year were:

  • In Jeremy's bracket contest, there is an inherent balance between getting a lot of points for an upset and, if you're wrong, getting 0 points for subsequent games. In this contest, by design you can't be completely out of a game, so this heavily skews results in favor of picking upsets. Note that that was the winning strategy for both the #1 and #2 entries last year.
  • In the occasional scenario where a low seed makes it to the final four (like #8 Butler in 2011 or both #5 Butler and #5 Michigan State in 2010), it's worth a disproportionate number of points. You can see this effect by the spike in the average points per game for round 4 below.
  • The contest is pretty much over before the final four games, especially since dropping the seed multiplier makes the game really low scoring.

To fix this, the rules will be changed as follows:

  • The value of the seed drops over time, so the Seed term is now essentially Seed / (Round+1). (The actual expression is more like floor(1+(Seed-1)/(Round+1)).) A #8 in round 4 would only be worth 2, and a #5 is only worth 1.
  • To increase the effect of subsequent rounds, the Round term has been changed from 5, 10, 15, ..., to 5, 15, 25, ..., which is expressed as (10*Round - 5).

Using the past few years as data points, you get the following distributions:

2011 Rules: 5 * Round * (Round <= 4 ? Seed : 1) 2012 Rules: (10 * Round - 5) * (Seed / (Round+1))
AvgPtsGame 2011.png AvgPtsGame 2012.png
AvgPtsRound 2011.png AvgPtsRound 2012.png
DistPtsRound 2011.png DistPtsRound 2012.png

How That Would Change Results

By applying those rules to last year's contest, the new results would be:

User Bot Name New Score Change In Rank
Michael O'Halloran There's No Need to Fear 1105.000 same
Darrel Hutchins Fibs, Lies, and Statistics 920.318 +2
Darrel Hutchins Big Stuff 914.974 same
Brent Cox PastPerformance 908.409 +3
Stock Low Seed Wins 895.000 -3
Michael O'Halloran Bot-tastic 868.206 +3
Stock Coin Flip 862.500 -1
Rick Bassham Random 861.616 -3
Stock High Seed Wins 830.000 +4
Daniel Reid Random 823.781 +2
Stock Split the Middle 773.535 same
Darrel Hutchins Déjà Vu 767.500 -2
Daniel Reid Contrarian 765.000 +1
David Jones Human Bracket 739.000 -2
David Jones High Seed Mostly Wins 738.869 same
David Jones Using Statistics 735.276 same
Brent Cox SOLOOLT 725.000 +1
Brent Cox Haven'tISeenYouBefore? 722.417 -1
Daniel Reid Contrarian 2 675.000 same
Michael O'Halloran Modified RPI 670.000 same

This shows "There's No Need To Fear" clearly dominating the competition. The last round is only worth 55 points, so it would have been over by then. The idea that a "low seed wins" variant can do so well is still troubling. I do like how much closer the rest of the field looks, though.