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Showing posts from April, 2019

March Performance Metrics, Updated

Back in 2015, I went down a bit of a math rabbit hole based on a curiosity of mine. I wondered if it was possible to quantify the performance of coaches and teams in the NCAA tournament in ways other than simply wins and losses, Final Fours, and National Titles.  In particular, I wanted to quantify under and overachieving in March. Along the way, I developed a few metrics that compared each coaches' and team's performance to the average performance of all other coaches / teams in similar tournament situations. Somewhere along the way, I discovered that others had also formulated a similar metric called "PASE" (Performance Against Seed Expectation).  My metrics were mathematically a bit different, and I settled onto two, one that I call PARIS (Performance Against Round Independent Seed) and PAD (Performance Against exact seed Differential).  Two years ago, I gave a pretty detailed mathematical description of each metric and summarized notable coaches performance base

The Variance of College Basketball Explained

Over the past 4-5 years, I have been fascinated by the subject of probability and variance on both college football and basketball. Specifically, I became interested in how the probability of victory changes with the Vegas point spread (which is still the most reliable predictor of the outcome of individual games). I have written quite a bit about this in the past, so I will just summarize those findings briefly now. There are several observations that I have made using a set of data from the "prediction tracker" website that covers data from 2004 through 2018.  First of all, teams that are favored by "x" points tend to win by an average of "x" points.  That data is plotted here: Furthermore, you can calculate the variance (i.e. the standard deviation) of the final score difference as a function of each point spread.  This value is a little above 10 points, with a fair amount of scatter, which increases a bit as the spread get larger. That data is

Odds of Bracket Perfection

With the One Shining Moment and the rest of the 2018-19 basketball season now in the rear-view mirror, it is that time of year to reflect on the past season and (if you are me) crunch a few more numbers based on yet another year of accumulated stats.  The first topic on my math to-do list is something that piqued my interested in the middle of this year's tournament.  After the first weekend, it was reported that a single person on-line had successfully picked every single tournament game (48 in total) correctly.  While this is clearly a tough thing to accomplish, the obvious question is "how tough?"  What are the odds of this kind of bracket perfection, and what is the "correct" way to calculate it? As you might expect, I am not the first person to think about this problem.  Warren Buffet perhaps stimulated most of this discussion when in 2014 he started to offer multi-million or even $1 billion dollar rewards for different variations on a perfect bracket, e

2019 Final Four Analysis

I am not sure about you, but I have had the NCAA Tournament theme music playing on a loop in my head for days.  The calendar may now say April, but we have one more weekend of March business to finish up with.  MSU will be playing it's 10th total Final Four this weekend, 8 of which were coached by Tom Izzo.  Will coach finally earn his 2nd title and the 3rd for MSU?  Let's take a look at some numbers to see who might be celebrating when One Shining Moment is playing amidst a fine rain of confetti on Monday night. The first thing that we can do is to look at the Vegas line and projected Vegas lines to see how the overall probabilities shake out, MSU is currently a 2.5-point favorite vs. Texas Tech. That is a little higher than Kenpom is projecting (1.3) and it gives MSU a 60% chance to advance. On the other side of the bracket, Virginia is a 5.5-point favorite over Auburn, which is a bit lower than Kenpom would project (6.3). That corresponds to a 71% chance that the Hoos adva