## USING KENPOM'S PYTHAG AND LOG5 METHOD TO PICK AN NCAA TOURNAMENT BRACKET

After staring at A Sea of Blue's post setting forth the odds for each of the NCAA Tournament teams to win it all for a half an hour, I concluded: whoa, numbers. But once I recovered, I thought it would be interesting to see how each game of the bracket plays out using Ken Pomeroy's data. Below is the NCAA Tournament bracket, with each region on top of each other (as opposed to the four regions facing each other in groups of two) because who among us has a 34" computer monitor? The play-in game is on top and the final four is on the bottom. The four digit number immediately next to each team is that team's pythag, and the percentages next to the pythags are those teams' respective "chances of winning" that game. For instance, based on their respective pythags, Mt. St. Mary's should beat Coppin State 88.85% of the time and so we'll consider them the winner and move them forward to play North Carolina. Yes, you can get the same result by looking only at the teams' respective pythags, but I think the percentages give you a better feel for how those numbers might play out on the court.

A couple of pre-post observations from hooper:

Pythag uses "pace-neutral" weighting, which means it compares the ratios of point differentials but not the actual values of point differentials. For example, a team that averages 80 pts. for and 70 pts. against looks identical to a team that averages 64 pts. for and 56 pts. against. KenPom does this so he doesn't have to worry about how many possessions a team normally has in a game. But that does make a big difference in the play of a game. So you lose valuable data at the start. This is normal for every numerical method, but it's good to know what is being lost. What this means is that Kansas has had the best pts. for / pts. against performance per possession in the league. But we don't know how many possessions is ideal for Kansas, or even if it makes a difference.

We also don't know the uncertainty. For example, if a team has a "70% chance of winning", does that mean 70% +/- 15%, or 70% + / 5%? If it's the first, then it's not unreasonable to see an upset. If it's the second, then an upset would be a tremendous shocker. We don't have a feel for the significance of a point spread, in other words.

If anyone wants to update the table to account for any of that, have at it. Start here, then read this, then read this. In the meantime, though, have a look at the table below, all dressed up in pretty Easter pastels for your enjoyment.

Oh, and one more thing: I've entered this bracket into the RTT ESPN Tournament Challenge so we can keep track of how well it does. If anyone calls Ken Pom an idiot because this entry doesn't finish in the top spot, I will personally come over to his house, pull out his toenails with a pair of pliers one by one every hour on the hour, write "no, you're the idiot" on each one in pink fingernail polish, and feed them to him. And Jackson the Mule will be right behind me to finish you off.

 PLAY-IN GAME Coppin St. .0984 11.15% Mt. St. Mary's Mt. St. Mary's .4651 88.85% EAST REGIONAL North Carolina .9739 97.72% North Car. .9739 68.35% North Car. .9739 60.04% North Car. .9739 57.00% N. Car. Mt. St. Mary's .4651 2.28% Indiana .9453 64.62% Indiana .9453 31.65% Arkansas .9044 35.38% Notre Dame .9375 81.77% Notre Dame .9375 37.65% Wash. St. .9613 39.96% George Mason .7698 18.23% Washington St. .9613 91.16% Wash. St. .9613 62.35% Winthrop .7067 8.84% Oklahoma .9065 58.80% Ok. .9065 25.61% L'ville .9657 55.91% L'ville .9657 43.00% St. Joseph's .8717 41.20% Louisville .9657 94.66% L'ville .9657 74.39% Boise St. .6135 5.34% Butler .9164 71.24% Butler .9164 33.05% Tenn. .9569 44.09% South Ala. .8157 28.76% Tennessee .9569 95.66% Tenn. .9569 66.95% American .5016 4.34% MIDWEST REGIONAL Kansas .9916 98.55% KS .9916 94.44% KS .9916 83.36% KS .9916 67.77% KS Portland St. .6341 1.45% UNLV .8742 56.62% UNLV .8742 5.56% Kent St. .8419 43.38% Clemson .9593 77.09% Clem. .9593 75.48% Clem. .9593 16.64% Villanova .8751 22.91% Vanderbilt .8845 77.03% Vand. .8845 24.52% Siena .6955 22.97% Southern Cal. .9443 43.59% Kansas St. .9564 28.09% Wis. .9825 63.13% Wis. .9825 32.23% Kansas St. .9564 56.41% Wisconsin .9825 96.04% Wis. .9825 71.91% Cal St. Fullerton .6984 3.96% Gonzaga .9300 55.84% Gonz. .9300 28.84% G'town .9704 36.87% Davidson .9131 44.16% Georgetown .9704 96.35% G'town .9704 71.16% UMBC .5539 3.65% SOUTH REGIONAL Memphis .9829 98.86% Mem. .9829 85.06% Mem. .9829 73.40% Mem. .9829 63.11% Mem. Texas-Arlington .3980 1.14% Mississippi St. .9099 51.43% Miss. St. .9099 14.94% Oregon .9051 48.57% Michigan St. .9542 79.25% Mich. St. .9542 57.34% Mich. St. .9542 26.60% Temple .8451 20.75% Pittsburgh .9394 78.88% Pitt. .9394 42.66% Oral Roberts .8058 21.12% Marquette .9612 79.98% Marq. .9612 49.04% Stan. .9626 43.37% Texas .9711 36.89% Kentucky .8611 20.02% Stanford .9626 94.31% Stan. .9626 50.96% Cornell .6082 5.69% Miami (FL) .8860 49.80% St. Mary's (Cal.) .8868 18.91% Texas .9711 56.63% St. Mary's (Cal.) .8868 50.20% Texas .9711 97.54% Texas .9711 81.09% Austin Peay .4590 2.46% WEST REGIONAL UCLA .9837 99.85% UCLA .9837 74.07% UCLA .9837 78.10% UCLA .9837 61.58% UCLA Mississippi Val. .0846 0.15% Brigham Young .8929 28.30% Texas A&M .9548 25.93% Texas A&M .9548 71.70% Drake .9418 74.66% Drake .9418 48.88% Conn. .9442 21.90% Western Ky. .8460 25.34% Connecticut .9442 88.81% Conn. .9442 51.12% San Diego .6807 11.19% Purdue .9402 62.32% Purdue .9402 44.97% Xavier .9506 33.82% Duke .9741 38.42% Baylor .9048 37.68% Xavier .9506 82.69% Xavier .9506 55.03% Georgia .8011 17.31% West Virginia .9433 49.95% AZ .9434 30.68% Duke .9741 66.18% Arizona .9434 50.05% Duke .9739 97.41% Duke .9741 69.32% Belmont .4977 2.59% FINAL FOUR North Carolina .9739 24.02% Kansas .9916 66.17% Kansas Kansas .9916 75.98% Memphis .9829 48.78% UCLA .9837 33.83% UCLA .9837 51.22%

## Trending Discussions

forgot?

### Please choose a new SB Nation username and password

As part of the new SB Nation launch, prior users will need to choose a permanent username, along with a new password.

Your username will be used to login to SB Nation going forward.

I already have a Vox Media account!

### Verify Vox Media account

Please login to your Vox Media account. This account will be linked to your previously existing Eater account.

### Please choose a new SB Nation username and password

As part of the new SB Nation launch, prior MT authors will need to choose a new username and password.

Your username will be used to login to SB Nation going forward.

We'll email you a reset link.

If you signed up using a 3rd party account like Facebook or Twitter, please login with it instead.

Try another email?

### Almost done,

By becoming a registered user, you are also agreeing to our Terms and confirming that you have read our Privacy Policy.

### Join Rocky Top Talk

You must be a member of Rocky Top Talk to participate.

We have our own Community Guidelines at Rocky Top Talk. You should read them.

### Join Rocky Top Talk

You must be a member of Rocky Top Talk to participate.

We have our own Community Guidelines at Rocky Top Talk. You should read them.