Monday, March 15, 2010

Upset Warning: Extra Possessions

I mentioned a couple times during my Tickets Punched series that rebounding and turnovers are key stats to look at for first round underdogs.  I wasn’t just pulling this assertion out of thin air, and I’ll lay out what evidence I have here.

Let’s start with the theory.  Teams in the first round of the NCAA tournament are often nervous, and I would expect that underdogs who usually win by outshooting their opponent might perform poorly due to nerves.  But teams that can overcome poor shooting by getting themselves extra possessions (via turnovers and rebounding) should do well.  And as a bonus, the other team’s nerves might assist them in forcing turnovers.

Last year, to test this idea, I looked at the performance of seeds 11 through 13 in the 2004-2009 tournaments.  Splitting the teams up based on their seasonal TO% margin ([def TO%] - [off TO%]) and Reb% margin ([Off Reb%] - [opp Off Reb%]), I found that teams who were positive in both were far more likely to pull upsets.  Picking teams who fit this description did an excellent job of predicting upsets last year.  Unfortunately, I lost that research in a hard drive crash, so I did something similar tonight, just so I have some kind of evidence to post.

This time, I used raw rebounding margin and turnover margin, because that was already in a database (from Bracket Science) that included NCAA seed and win information for the last 4 tournaments (2006-09).  Once again, I looked at seeds 11 to 13.  Overall, they won 17 of 48 games (35%).  There were 28 teams that had positive rebounding and turnover margins, and they won 14 games (50%), leaving 3 wins for the other 20 teams (15%).  This time I noticed one more criteria that seemed to split the teams, and that was RPI SOS.  Narrowing it down to only teams with a SOS of 150th or better, the upset tally improves to 12 of 17 (71%), which means other teams are 5 of 31 (16%).  Here’s a summary chart, for those who like numbers more than words:

image

And here is a list of all the teams from the past 4 years that met the criteria, as well as how they did in the tourney:

image

I’m not suggesting you pick all 6 of the 2010 teams to make it out of the first round… but I am suggesting, you shouldn’t be surprised when one of them does.

When your bracket falls apart after taking my advice, feel free to email me with angry screeds!

2 comments:

  1. Fascinating stuff. I'm intrigued by your early successes. Look forward to what your model says about Vanderbilt-Murray St., since most of our fans are in denial about our low efficiency.

    ReplyDelete
  2. Thanks Philip, I'm intrigued as well. As you can see above, Murray State is NOT on the upset watch list this year.

    As for my similarity predictions, I haven't had time to update my database to include the results of the conference tournaments yet. But using data that is a few days old, my system shows Vandy with a 74% chance of winning, compared to only 60% using the straight Pomeroy numbers. So Vandy is relatively safe - but there are no gimmes in the NCAA tourney (outside the 15/16 seeds).

    ReplyDelete