By DAVID BORAKS
Basketball fans are filling out brackets for the NCAA men’s basketball tournament that begins Thursday, and their strategies vary wildly. Some pick the higher seeds. Others look at everything from team height to the cost of tuition at schools. At Davidson College, math professor Tim Chartier and his students are sticking to the data.
JOIN IN! You can use their calculator to pick – see below
The stakes are higher than ever this year, well beyond bragging rights. Rich man Warren Buffett has offered a billion dollars if someone can pick all 63 tournament games accurately.
Chartier and his students haven’t done that over the past few years, but they have beat most of the rest of us. A 2009 bracket beat more than 97 percent of the brackets submitted to ESPN. In 2010, the first time Chartier taught the lesson in class, their bracket beat more than 99.9 percent of more than 5 million ESPN entries. (See April 6, 2010, “In math-driven NCAA brackets, we have a winner.”) Last year, Jane Gribble, a Davidson cheerleader and math major, beat more than 96 of the 8 million-plus brackets, Chartier said.
But it hasn’t always worked so well. In 2011, the class brackets picked just under 80 percent. “But,” he notes, “We didn’t find sports analysts that beat us. There is always a certain amount of randomness that enters that madness and sometimes, things can fall far, far from the odds.”
This year, their numbers-driven strategy is continuing to evolve, and they’re getting a fair amount of national attention, from The New York Times to CBS to USAToday.
Over the years, Chartier has added variables, (home vs. away record, recency of victories, strength of opponents). “This year, I have a group of Davidson undergraduates trying totally new ideas,” he said. “It’s been fun to talk about them with Business Week, Bloomberg TV, and FIveThirtyEight.com and have them quite interested in our approaches.”
So how do they do it? As any mathematician would, constructing a problem – a series of simple equations – that take into account a variety of factors. With so many different equations, the calculation requires a computer. Here’s how Chartier describes it:
“We solve linear systems, which is a topic in the middle school curriculum. Like:
X + Y = 5
X – 2Y = 8
But, we have about 350 unknowns and equations. In the example above we had 2 of each. Why? We rank all (close to) 350 teams over about 5,000 games. The unknowns are the ratings of the teams. We are trying to discern strength of schedule so that my rating is, in part, based on how strong of opponents I faced. We have computers solve such large systems and form them from that amount of data.
Then, we add in the ability weight elements of play, like time. This is where you are trying to upweight something like recent games.”
Jordan Wright, one of the math student prognosticators, said the process takes “a lot of patience. I had to look at a lot of results and rankings over the past few weeks!”
He’s been looking at the scoring margins, and he thinks they may not tell the whole story. “At times, a final scoring margin of a game may not reflect the nature of a game. For instance, a team may lead the majority of a game by 3 to 6 points, then win by 10 points due to fouling and free throws at the end of the contest. The final margin may be 10, but that would not be a true portrayal of the game. Thus, I have tried to limit scoring margin in some of my methods. In some cases, I have completed and strictly used wins and losses.”
Want to give it a try? Make your own choices and join Davidson College students and Chartier in a bit of mathematical March Madness – or March Mathness – at MarchMathness.davidson.edu
“The parameters can take some practice but once you get it, it’s easy,” Chartier said. “It was developed as a teaching tool for my presentations. But, the media has made it a tool being used around the world. We’ve had people in Germany, India, Pakistan and Japan as well as all over the US with close to 10,000 uses.”
Oh, and for the record: Chartier’s carefully calculated bracket – filled out with son Noah – has Arizona wearing the crown. He won’t see students’ brackets until later Thursday (after a midday deadline – the tournament’s start.)
Not all the brackets will be the same, as each student decides to weigh variables differently. ”I can hardly wait to see their math decisions unfold,” he said.
RELATED LINKS AND COVERAGE
March Mathness bracket challenge, MarchMathness.davidson.edu
March 18, 2014, New York Times, “Plenty of Ways to Try for a Billion-Dollar Prize”
March 18, 2014, New York Times, VIDEO: “The Mathematician vs. the Matildas.” - Davidson professor Tim Chartier and a group of young actresses from Broadway’s “Matilda” talk about how they pick their brackets.
April 6, 2010, “In math-driven NCAA brackets, we have a winner.”)
March 19, 2010, “Can math beat your March Madness bracket? Yep”by