Monday, March 9, 2015

Time for Torvik's annual beatdown

It's March, so that means it's time for me to destroy Torvik in the Big Ten tournament bracket challenge. I'll post my picks first and we can laugh at his later.

Wed
PSU over Nebraska
Minn over Rutgers

Thur
IL over MI
Iowa over PSU
NW over IU
OSU over Minn

Fri
UW over IL
Iowa over Purdue
Maryland over NW
OSU over MSU

Sat
UW over Iowa
Maryland over OSU

Sun
UW over Maryland

Sunday, March 8, 2015

All Big Ten

 I am trying something new with the All Big Ten team. All Big Ten by class. Here's how I think it should look:

Seniors:
Kaminsky, Aaron White, Brandon Dawson, Dez Wells, DJ Newbill
I felt these choices were pretty obvious. There is not a ton of depth beyond the top 5 seniors, which bodes well for a fun Big Ten next year with lots of talent coming back. Rice missed too many games, and Trice was too inconsistent.

Juniors:
AJ Hammons, Dekker, Jake Layman, Yogi, Petteway
Hammons had a comeback player of the year type season if that was an actual award in college. Dekker and Layman were very good on great teams and could have put up huge numbers on a worse team or if they were more selfish. Yogi is Yogi. Petteway just had no help this year.

Sophomores:
Hayes, Malcolm Hill, Troy Williams, Koenig, Zach Irvin
Hill and Koenig got huge mid season opportunities when Rice and Jackson got hurt and both took full advantage. The last spot cam down to Nunn and Irvin. I gave it to Irvin because after Walton and Lavert went down he stepped up and helped MI get to 8 wins. This class also doesn't have a ton of depth but I expect to see a bunch of the 2nd tier guys step up next year as juniors.

Freshman
Melo Trimble, D'Angelo Russell, James Blackmon, Bryant McIntosh, Jae'Sean Tate
The top 3 are easy. The rest were tough as the freshman class is loaded, especially at guard. The Big Ten will have fun players to watch in the coming years. Tate reminds me so much of a young Alando Tucker. I have little doubt he will be great and was super fun to watch this year. He took away a starting spot from a bunch of more experienced players on a good team.

Evaluating the predictions

I feel OK about the predictions this year. It wasn't a great year, but not awful like last year. This was a young Big Ten with a lot of new faces which made it harder to predict than normal, plus there was the addition of 2 new teams (I missed on both). If I got it right or within 1 that's a win in my book. Within 2 is a push. Everything worse that that is obviously bad. Of the misses there weren't any glaring errors like my 8 game miss with Nebraska last year. I was no more than 4 games off with any team. Despite adding 2 teams, I had the same number of misses (5) as last year. I'll only address the misses.

The wins this year are UW, MSU, MI, IL, Indiana, NW
The pushed are PSU, Minnesota, OSU
Misses are Rutgers, Purdue, Nebraska, Iowa, Maryland

Rutgers- One of the two new teams I missed on. I actually had them with 3 wins on my first draft but the total wins and losses didn't add up right. I added a couple wins for them thinking they might pick off some of the mediocre middle at home, but was wrong. I blasted this team in my preseason A-rank and predicted they would be the worst team in the big ten, so I don't feel too bad about the 3 game miss.

Maryland- The other new team I missed on. This team was tough as I didn't know much about them coming in, plus they had 4 freshman in the rotation, plus Wells and Smotryz missed a bunch of games early with injuries. I underrated this team and they kept getting better as the season went along.

Purdue- Speaking of teams with lots of freshman and getting better as the season went along. This is the 2nd year in a row I have missed on Purdue. I feel like I didn't trust my eyes enough on this team. It was obvious this team was vastly improved over last year but I was too chicken to pick more wins. I don't think many saw a 12-6 season, but I should have been better than 4 games off.

Nebraska- This is 2 years in a row missing on this team too. I blasted this team in my A-rank, but again I didn't trust my eyes enough to downgrade them appropriately. They got pretty much the same numbers out of Petteway and Shields but the supporting cast stunk and they averaged 6 fewer points per game as a team. The problem was shooting, as they were a God awful 28.6% from 3 while taking 36% of their FGA from 3.

Iowa- After 3 years of .500 basketball, Iowa finally broke through with a 12-6 season just as I gave up on them. Aaron White was incredible, and Jok got better and better as the year went along to give them something from the perimeter to go with that strong front court.

Thursday, March 5, 2015

How good (or bad) is Wisconsin's defense, really?

If you compare the Kenpom ratings to the T-Rank, one difference that may jump out is that Kenpom ranks Wisconsin's defense 48th in adjusted defensive efficiency, and T-Rank has it ranked 24th. That's a fairly large and significant difference, particularly if you're one of those people who filters out national championship contenders by metrics such as "top 25 in both offensive and defensive efficiency" or some such thing.

So what accounts for this difference? Basically, the difference is caused by a rather extreme feature of Kenpom 2.0: it deeply discounts (sometimes all but ignores) the results of mismatched blowouts. So Wisconsin's opening game demolition of Northern Kentucky -- which Wisconsin held to an incredible .526 points per possession -- likely doesn't much figure into Wisconsin's Kenpom rating.

To see how drastic this Kenpom 2.0 adjustment affects the Badgers, compare their defensive numbers to Villanova. If you look at the raw efficiency numbers, Wisconsin and Villanova have essentially identical numbers:


Team Raw DE Raw DE Rank
Wisconsin 93.5 23
Villanova 93.3 21

This is just "total points allowed divided by total possessions" and by this metric the two defenses are very similar.

But Wisconsin's raw defensive efficiency gets adjusted significantly downward, while Villanova's gets adjusted slightly upwards:

Team Adj DE Adj DE Rank
Wisconsin 94.9 48
Villanova 93.1 20

You might think this adjustment is being made based on strength of schedule -- perhaps Villanova has just played better offensive teams, which would naturally lead to an adjustment in their favor. But according to the Kenpom numbers, that isn't so:

Team Opp. Adj OE Rank
Wisconsin 105.0 51
Villanova 104.9 56

So strength of opponent would favor Wisconsin, if anyone.

Other than strength of opponent and adjustment for mismatches, the other adjustment that could affect the ratings is recency. Kenpom weighs more recent games more heavily than older games (as does T-Rank). But this is a minor factor, and cannot explain the large downward adjustment compared to Villanova. Besides, Wisconsin has been playing better on defense recently.

The T-Rank algorithm discounts the effect of mismatches too, but obviously not as aggressively. I'm quite certain that this accounts for the difference in the adjusted defensive ratings. Many of the Badgers' most impressive defensive performances have come in the kinds of games (such as the Northern Kentucky game) that Kenpom 2.0 discounts or ignores.

There's reason to believe the T-Rank is closer to the truth. One clue to this is that Kenpom had Wisconsin's adjusted DE ranked in the 80s just a few games ago. Meanwhile, T-Rank has consistently had Wisconsin's adjusted DE ranked much higher, in the top 35 all along, and it has therefore more accurately predicted the Badgers' performance in recent games.

One of the fun things about doing the T-Rank this year is that it has given me some insights into the vagaries of the Kenpom ratings. They have amply earned their status as "authoritative" but they are not perfect, and they are by no means the simple application of god-given math. Judgments are involved, and sometimes those judgments -- even if they are correct in the macro sense that they will most often produce better predictions for most teams most of the time -- sometimes produce error.