Monday, February 21, 2011

NOTEBOOK: Adjusted Efficiency Margin Tells The Story

The weekend's events have shuffled the Adjusted Efficiency Margin standings, as Harvard closed the entire 5.6 point gap with Princeton and took a minor lead.

The Crimson has jumped ahead despite a 12.2 percentage point gap in free throw "defense," though that was much larger before Brown sank 25 of its 27 attempts Saturday night.

Brown        98.7      104.4 -5.8
Columbia        95.7      102.5 -6.7
Cornell      103.1      109.1 -6.0
Dartmouth        84.9      104.9 -20.0
Harvard      107.8        98.7 9.1
Penn        99.4        97.7 1.7
Princeton      100.8        92.7 8.1
Yale        95.8        97.2 -1.3

For the Crimson, the adjusted offensive efficiency only moved slightly over the weekend, ticking up from 107.1 to 107.8, but it was the defense that made the largest move (-2.9), as it yielded just 102 points on 112 possessions on the road against two opponents whose offenses net to the national average.

Meanwhile, Princeton moved the other direction, as it survived its second-worst offensive showing of the year by playing outstanding defense at Yale, but couldn't salvage a victory after recording its third-straight sub-100 offensive efficiency performance at Brown. The Tigers' defense remains the league's best by a wide margin, but Princeton is really struggling to score points right now.

Penn snapped the third place tie with Yale seeing a tick up on offense and tick down on defense about a half point to keep its adjusted efficiency margin in positive territory. The Bulldogs hurt themselves in getting swept at home by the Tigers and Quakers, but the drop came entirely in the offensive category, after Yale laid an egg against Princeton, scoring just 51 points on 62 possessions.

In the bottom half of the league, only Columbia sticks out. The Lions are currently tied for fourth with Yale but have posted an adjusted efficiency margin much closer to that of the two Ivy teams tied for sixth at 3-7. That's primarily because it is 5-2 against teams not named Harvard and Princeton with only eight- and five-point road losses, but 0-3 against the top two with an average margin of defeat of 20 points per game. Brown and Cornell, meanwhile, have been less successful in their toss up games, while playing the league leaders close at least once.

STAT 100

Team  ORatVar  DRatVar CoVar ORank DRank
Brown        11.4        11.3 42.4            5          4
Columbia        11.7        11.0 -4.6            4          6
Cornell        13.6        12.3 99.9            1          2
Dartmouth        12.8        10.3 13.3            3          8
Harvard        11.2        11.6 19.5            6          3
Penn        11.0        10.6 11.5            7          7
Princeton         8.6        11.1 10.0            8          5
Yale        13.4        13.1 91.9            2          1

As has been discussed all season, Princeton continues to boast the offense with the least variance by a wide margin. Its defense also remains among the league's least volatile. Sure enough, among the Tigers' nine Ivy games thus far, six have seen offensive efficiency ratings ranging from 93 to 108 - within one standard deviation of the 100.8 mean in league play - while only one performance has pushed the bounds of the second standard deviation (117.9 at Columbia).

Consistency is good, especially over the course of a 14-Game Tournament, but it does establish a lower ceiling offensively, something that can make it hard to chase down a Brown team on a night when the defense is failing.

The highest variance teams in the league remain Cornell and Yale, but quite striking is the covariance number. As a brief refresher, a highly positive covariance number means that the offensive and defensive efficiency ratings are correlated, specifically that as the Big Red or Bulldogs play better offensively, they are also likely to start playing worse defensively (remember rising defensive efficiency ratings indicate worse defense). The converse is also true - as Cornell and Yale struggle more offensively, they clamp down more on the defensive end.

The end result is that the two teams' performance as a whole winds up being less high variance than their individual offensive and defensive variances would indicate.


According to the simulations, there is still about a 22 percent chance of a two-team playoff between Harvard and Princeton to decide the Ivy League's automatic bid to the NCAA tournament - about the same level as when the season began.

The league office has yet to finalize any plans, but has begun discussing potential venues and dates. So far, John J. Lee Amphitheater (Yale) and Levien Gym (Columbia) are the two Ivy League sites being discussed, and the league is considering non-Ivy sites as well. The potential dates would be Thursday, March 10th, Friday, March 11th or Saturday, March 12th, with Friday or Saturday being the most likely.

The last potential playoff situation heading into the final weekend of the season was in 2009, when Cornell (9-3) led Princeton (7-4), Yale (7-5) and Dartmouth (7-5), heading into the final weekend. The league announced the potential playoff site - Levien Gym - during the week before those closing contests.

The last two non-Ivy playoff locations to be used (Lafayette, 2001 and Lehigh, 1996) wouldn't make much sense this time around, given that Eastern Pennsylvania isn't all that close to the midpoint between Harvard and Princeton.

1 comment:

  1. Interesting on the venue. If one goes strictly by geography and picks a mid-point between Harvard and Princeton, the John J. Lee Amphitheater @Yale best fills the bill.

    There are probably other considerations. For instance, if one thinks that the playoff game could draw a huge crowd (really??), Hartford Civic Center might be another choice.