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Sunday, March 17, 2019

NCAA Tournament 2019 Bracket Math for the MDS Model

Another year, another attempt to quantify the 9.2 quintillion outcomes of the NCAA tournament via my MDS ModelAs I did last year, I've generated a composite set of rankings similar to what I used to sportsbet in Las Vegas. 

I'm taking a composite of 4 different models, similar to what FiveThirtyEight does, and the same technique as last year: 
  • FiveThirtyEight (so I'm including a composite of a composite)
  • KenPom (who's ratings are also included in FiveThirtyEight, so they're counted twice)
  • Powerrank (created and maintained by Ed Feng)
  • Massey Composite (another composite, this time spanning 68 rating systems)
I then use a weighted average of these 4 ratings that reduces outliers by weighting the ratings closer to the median higher. This smooths out the final Aggregate ratings that I then use to project the tournament. That being said, I have a good deal of trust in all of the above rating systems, so I wouldn't expect anything too crazy outlier-wise.

Note: For simplicity, I've taken the highest rated team in each play-in game and included them.


SeedTeam1st Round2nd RoundSweet 16Elite 8Final FourChampionshipChampion
East
1Duke100.00%98.28%80.11%58.13%37.81%23.02%13.77%
16*North Dakota St.100.00%1.72%0.19%0.01%0.00%0.00%0.00%
8VCU100.00%52.72%10.84%4.40%1.45%0.42%0.12%
9UCF100.00%47.28%8.86%3.37%1.03%0.27%0.07%
5Mississippi St.100.00%71.93%35.26%11.71%4.84%1.79%0.64%
12Liberty100.00%28.07%7.99%1.33%0.29%0.05%0.01%
4Virginia Tech100.00%82.67%51.90%20.43%9.82%4.27%1.81%
13Saint Louis100.00%17.33%4.85%0.62%0.11%0.02%0.00%
6Maryland100.00%63.24%33.30%12.12%4.21%1.50%0.52%
11*Belmont100.00%36.76%14.67%3.69%0.88%0.21%0.05%
3LSU100.00%77.18%45.15%17.98%6.85%2.67%1.01%
14Yale100.00%22.82%6.88%1.15%0.18%0.03%0.00%
7Louisville100.00%63.56%21.80%11.86%4.39%1.66%0.61%
10Minnesota100.00%36.44%8.49%3.48%0.89%0.23%0.06%
2Michigan St.100.00%95.13%68.98%49.62%27.24%15.29%8.42%
15Bradley100.00%4.87%0.73%0.11%0.01%0.00%0.00%
West
1Gonzaga100.00%98.16%77.94%56.95%36.19%20.95%12.22%
16*Fairleigh Dickinson100.00%1.84%0.19%0.01%0.00%0.00%0.00%
8Syracuse100.00%52.65%11.98%5.26%1.77%0.51%0.15%
9Baylor100.00%47.35%9.89%4.09%1.28%0.34%0.09%
5Marquette100.00%61.83%29.61%9.60%3.69%1.23%0.41%
12Murray St.100.00%38.17%14.01%3.23%0.90%0.21%0.05%
4Florida St.100.00%77.73%48.91%19.61%9.17%3.78%1.57%
13Vermont100.00%22.27%7.47%1.25%0.26%0.04%0.01%
6Buffalo100.00%67.41%30.14%12.68%4.93%1.80%0.66%
11*Arizona St.100.00%32.59%9.45%2.49%0.60%0.13%0.03%
3Texas Tech100.00%85.61%56.58%29.81%14.67%6.89%3.26%
14Northern Kentucky100.00%14.39%3.83%0.65%0.10%0.01%0.00%
7Nevada100.00%55.72%20.65%9.27%3.46%1.21%0.43%
10Florida100.00%44.28%14.23%5.62%1.82%0.55%0.17%
2Michigan100.00%91.50%63.47%39.22%21.13%10.91%5.68%
15Montana100.00%8.50%1.65%0.26%0.03%0.00%0.00%
South
1Virginia100.00%97.08%79.91%60.52%41.42%27.37%16.33%
16Gardner Webb100.00%2.92%0.49%0.06%0.01%0.00%0.00%
8Ole Miss100.00%47.66%8.96%3.62%1.18%0.36%0.09%
9Oklahoma100.00%52.34%10.64%4.54%1.58%0.51%0.13%
5Wisconsin100.00%65.06%39.24%14.18%6.74%3.03%1.16%
12Oregon100.00%34.94%15.92%3.80%1.26%0.39%0.10%
4Kansas St.100.00%73.61%37.56%12.18%5.29%2.16%0.74%
13UC Irvine100.00%26.39%7.28%1.10%0.24%0.05%0.01%
6Villanova100.00%59.52%27.21%11.61%4.07%1.62%0.54%
11Saint Mary's100.00%40.48%14.96%5.08%1.38%0.43%0.11%
3Purdue100.00%83.84%53.53%28.10%12.47%6.21%2.67%
14Old Dominion100.00%16.16%4.29%0.82%0.12%0.02%0.00%
7Cincinnati100.00%53.51%18.09%7.55%2.30%0.80%0.23%
10Iowa100.00%46.49%14.36%5.52%1.52%0.48%0.12%
2Tennessee100.00%90.71%65.40%40.95%20.39%11.31%5.50%
15Colgate100.00%9.29%2.15%0.36%0.04%0.00%0.00%
Midwest
1North Carolina100.00%97.40%75.57%51.86%32.56%17.61%9.22%
16Iona100.00%2.60%0.31%0.02%0.00%0.00%0.00%
8Utah St.100.00%52.59%13.17%5.41%1.90%0.53%0.14%
9Washington100.00%47.41%10.96%4.24%1.39%0.36%0.09%
5Auburn100.00%69.60%40.97%17.73%8.70%3.53%1.36%
12New Mexico St.100.00%30.40%11.99%3.08%0.93%0.22%0.05%
4Kansas100.00%75.14%40.04%16.31%7.56%2.87%1.04%
13Northeastern100.00%24.86%7.01%1.34%0.30%0.05%0.01%
6Iowa St.100.00%63.22%33.30%15.04%6.44%2.44%0.87%
11Ohio St.100.00%36.78%14.74%4.84%1.49%0.39%0.10%
3Houston100.00%82.63%47.90%23.09%10.59%4.31%1.67%
14Georgia St.100.00%17.37%4.06%0.70%0.11%0.01%0.00%
7Wofford100.00%61.22%22.60%10.62%4.08%1.37%0.43%
10Seton Hall100.00%38.78%10.64%3.85%1.10%0.27%0.06%
2Kentucky100.00%92.90%65.48%41.68%22.84%11.31%5.40%
15Abilene Christian100.00%7.10%1.28%0.18%0.02%0.00%0.00%

Some quick reactions:


  • North Carolina seems to have the toughest route, but also has the lowest rating in my model of the 1 seeds. These two combined factors result in the lowest probability of the 1 seeds of reaching the Final Four (32.56%)
  • Of course Virginia has the lowest chance of winning their first game out of all the 1 seeds (97.08%)!
  • The fan base that has the best right to complain is Michigan St: they're #4 overall, yet get #2 Duke in the Elite Eight, and only have a 27.24% chance of reaching Minneapolis
The top 12 teams in the tournament are as follows:


RankTeamRating
1Virginia95.38
2Duke94.78
3Gonzaga94.23
4Michigan St.93.03
5North Carolina92.71
6Michigan91.94
7Tennessee91.40
8Kentucky91.05
9Texas Tech90.22
10Purdue89.35
11Virginia Tech88.43
12Florida St.88.10

5 of these top 12 are ACC, which is a real testament to the strength of the conference. The Big 10 has 3, the SEC has 2, and the Big 12 only has 1.


A word of caution about straight up copying the above: in most pools you want to gauge "contrarian" picks relative to the overall poolMy suggestion would be to use the above probabilities as a guide ("I'm just a guide"), and make contrarian picks that have a good chance of happening (like picking a champion that has solid odds but isn't necessarily the favorite).

Michigan St or Tennessee Will (Likely) Be the Team Left Off the 1 Line

Note: The following post was compiled before the SEC and Big 10 championship games had been played

Due to a couple of results from the past week, the four #1 seeds in this year's tournament are far from certain. Virginia and Dook are in (and one of them will be #1 overall), but there are conceivably 4 teams for the last 2 spots. Will the ACC get three #1 seeds, something a conference has done only once before? Will Gonzaga remain on the top line even after losing handily to a bid stealer? Or will the SEC and Big 10 get one or both?

I'm using the Bracket Matrix to try to answer this question, which is a compilation of 51 publicly available brackets, all trying to predict what the committee will do in a few hours. This compilation currently has North Carolina barely hanging on to the last #1 seed and Gonzaga solidly at #3 overall. But mine is a bigger question: who is getting boxed out of the top line?

I'm assuming that Kentucky has no shot; "Only twice in the past nine years has a 1-seed been given to a team that didn't win either its regular-season or conference tournament title." So that leaves the other 4 described above, Gonzaga/North Carolina/Tennessee/Michigan St. I then looked at every #1 seed combination on the Bracket Matrix:


Top LineCount
Virginia,Duke,Gonzaga,North Carolina24
Virginia,Duke,Gonzaga,Tennessee12
Virginia,Duke,North Carolina,Tennessee7
Virginia,Duke,Gonzaga,Michigan State3
Virginia,Duke,Tennessee,Michigan State2
Virginia,Duke,North Carolina,Michigan State1
Virginia,Gonzaga,North Carolina,Tennessee1
Virginia,Duke,North Carolina,Kentucky1
Total51

We can really ignore the last 2, which were last updated before Dook won and Kentucky lost yesterday. Of the rest, each team was left out:

Team# Times Left Out
Michigan State31
Tennessee25
North Carolina17
Gonzaga8

The ideological differences in the brackets are interesting. It looks like it comes down to Gonzaga vs Tennessee, as 31 of the 49 predictions I considered only contain one of these two schools, and only 12 leave off North Carolina in favor of BOTH Gonzaga and Tennessee. And none of these combined 43 have Michigan St. 

We'll see tonight if the committee follows the majority of forecasters here (31/49) and chooses one of Gonzaga or Tennessee, or if they go contrarian (12/49) and leave off North Carolina.

Wednesday, March 13, 2019

2019 ACC Bracket Math

It's March! And the ACC tournament being moved forward a day has thrown me off again (thanks John Swofford!)

Here are the tournament ratings and probabilities anyway, using a composite of the Massey Composite and Kenpom:


SeedTeamRating
1Virginia0.919
2North Carolina0.874
3Duke0.892
4Florida St.0.826
5Virginia Tech0.844
6Syracuse0.781
7Louisville0.817
8North Carolina St.0.788
9Clemson0.795
10Georgia Tech0.684
11Boston College0.677
12Miami FL0.720
13Wake Forest0.616
14Pittsburgh0.685
15Notre Dame0.698


SeedTeam2nd RoundQuartersSemisFinalChampion
1Virginia100.00%100.00%75.00%53.07%33.67%
8North Carolina St.100.00%48.99%12.06%5.36%1.98%
9Clemson100.00%51.01%12.94%5.88%2.22%
4Florida St.100.00%100.00%52.77%18.91%8.02%
5Virginia Tech100.00%71.39%38.05%14.75%6.72%
12Miami FL61.56%19.82%6.96%1.66%0.48%
13Wake Forest38.44%8.79%2.22%0.37%0.08%
2North Carolina100.00%100.00%65.85%34.24%16.57%
7Louisville100.00%66.56%26.00%10.79%4.11%
10Georgia Tech48.31%15.78%3.74%0.98%0.23%
15Notre Dame51.69%17.66%4.41%1.21%0.30%
3Duke100.00%100.00%73.38%43.28%22.67%
6Syracuse100.00%62.57%18.91%7.35%2.45%
11Boston College49.09%18.16%3.68%1.01%0.23%
14Pittsburgh50.91%19.27%4.02%1.13%0.27%

Note that I'm not using any kind of adjustment to categorize Charlotte (this year's site) as a "semi-home" for Dook or Carolina. Even so, Virginia is not as large a favorite as last year since both of those powerhouses are also so good this year (three 1 seeds??). Those 3 teams combine to win this tournament about 3/4 of the time.

Friday, December 21, 2018

Kia Soul Fuel Efficiency on ECO Mode

My 2015 Kia Soul has an "eco mode", which supposedly "helps the models to achieve a higher level of fuel economy by adjusting the engine and transaxle operating parameters". I usually have left it on since I drive quite a bit, with a 47-mile one way commute (94 miles round trip daily). Thing is, I have had no idea whether it actually does anything. It certainly makes changing gears slower, which makes it way harder to accelerate and sometimes feels like I'm driving a golf cart. Which certainly isn't ideal when I'm predominately driving on highways.

So over the past 3 months, I've started tracking splits of my mileage, gas fill ups, etc based on whether I have the "eco" button ON or OFF. Over a full timetable of 7,685 miles driven over 20 fill ups since 9/17/18, I've experienced the following performance per fill up:


EcoMiles DrivenGalMPGCount
ON348.012.3128.2810
OFF351.112.6527.7710
Total349.612.4828.0220

So the eco mode actually does have an effect! My fuel efficiency is about
0.51 miles per gallon better when I have eco mode turned on. 

The car also gives an "estimated" range every time I fill it up, and these "estimates" certainly don't reflect what my tracking has shown me, skewing high in both cases and also a much smaller predicated delta between ON/OFF (0.18 miles per gallon):


EcoEst RangeGalEst MPGCount
ON354.112.3128.7710
OFF361.612.6528.5910
Total357.812.4828.6820

So how much am I actually saving? Is it worth feeling like I need to start pedaling like Fred Flintstone in order to squeeze out another 0.51 miles per gallon? The current average gas price in Miami is around $2.35 per gallon, but over the course of my tracking I've been spending closer to $2.64 per gallon. So my savings would be:

0.51 miles per gallon * $2.64 per gallon * 1.56 savings per week = $2.10 per week

Is it worth ~$2 a week, or ~$104 a year, for a worse driving experience? Considering that I'm driving almost 100 miles round trip each day, 5 days a week, I think I'll leave eco mode OFF going forward.