The Ken Pomeroy Effect: How Advanced Metrics Have Revolutionized NCAA Basketball

C.J. Moore@@CJMooreHoopsCollege Basketball National Lead WriterMarch 7, 2013

NEW ORLEANS, LA - APRIL 02:  The Kentucky Wildcats celebrate after defeating the Kansas Jayhawks 67-59 in the National Championship Game of the 2012 NCAA Division I Men's Basketball Tournament at the Mercedes-Benz Superdome on April 2, 2012 in New Orleans, Louisiana.  (Photo by Chris Graythen/Getty Images)
Chris Graythen/Getty Images

In nearly two weeks, when the brackets are released, the first thing many fans and coaches will do is open their laptops and pull up KenPom.com.

Databases of numbers will pop up, stats which only 10 years ago were foreign to most of the basketball population and these days are showing up on ESPN broadcasts.

The godfather of the movement is weatherman-turned-college-basketball-guru Ken Pomeroy.

Pomeroy’s site is filled with information on every team, breaking down team performance with terms like “offensive efficiency” and “defensive efficiency,” which measure how many points a team scores and allows per 100 possessions and is adjusted according to opponent strength.

“The main thing is I think it just gives people a better understanding of what a team's or a player's strengths and weaknesses are,” Pomeroy said in an interview from his home in Salt Lake City, where he runs his subscription-based site.

That knowledge is extremely valuable to coaches, and many are adapting quickly.

Miami coach Jim Larranaga told CBSSports.com’s Gary Parrish recently that advanced stats have helped him turn around his program.

"The only rankings that are important to me are the rankings of the KenPom.com stats in all of the categories that determine success or failure,” Larranaga told Parrish. "I value those statistics. I value them for motivation."

Florida coach Billy Donovan, as told to Eddie Matz in ESPN The Magazine last month, noticed that the teams that made the Final Four last season all ranked in the top 10 in adjusted defensive efficiency on Pomeroy’s site.

"I've been a big believer in advanced metrics," Donovan said. "But I had never discussed it with my players.”

Donovan, like Larranaga, decided to use it as a motivational tool this year, and his Gators went from the 71st-ranked defense last season to the second-ranked defense and top-rated team on KenPom.com this season.

Pomeroy and advanced statistics are changing the way coaches think about the game, and possibly even the outcomes of the games themselves.

How It Started

If Pomeroy is the godfather of the college movement, the godfather of advanced stats in basketball altogether is Dean Oliver, who wrote the book “Basketball on Paper,” published in 2004. Oliver works for ESPN now and educates and informs viewers from behind the scenes.

Oliver’s work was the basketball version of Bill James’ sabermetrics, which have engulfed the baseball community, known to many as “Moneyball.”

Pomeroy had no idea who Oliver was when he launched his blog in 1999. He got his start mostly generating his own power rankings for multiple sports.

“I started blogging with the idea of an analytical blog,” he said. “I probably had about 20 readers.”

Soon thereafter Pomeroy began building his rankings for college basketball based upon data he was collecting that went beyond just the score, using numbers similar to the ones Oliver introduced.

“The way he thought about things was the way I thought about things,” Pomeroy said. “He just sort of accelerated that process for me.”

Right before the NCAA tournament in 2004, Pomeroy published the data on his site.

“At that time, advanced stats in baseball was really kind of catching on and there were a lot of blogs written about it. I was big into that kind of stuff,” Pomeroy said. “Rob Neyer was a big influence, he was writing about it for ESPN.com, and there was nobody doing anything about it for college basketball. So that was really the motivation. I was kind of curious about that kind of thing. If somebody else were doing it, I probably wouldn't have gotten started. I would have been reading what other people were doing.”

The popularity of Pomeroy’s site mostly grew through word of mouth, and he said he saw it take off when coaches and national media started referencing it.

"I pretty quickly realized the information I was mining was useful to other people," he said.  

Eventually, he had enough traffic that he could charge for subscriptions, and this past August he quit his job with the national weather service to focus exclusively on hoops. Pomeroy runs the day-to-day operations of his site and also does consulting work for Iowa State coach Fred Hoiberg.

Pomeroy’s partner in analytics early on was John Gasaway, who now covers college basketball at ESPN.com. Gasaway was introduced to advanced stats by Oliver’s book and got his start by running a blog called Big Ten Wonk.

In 2007, Gasaway quit his career in marketing to focus on hoops. Several months later, Gasaway and Pomeroy were hired on as the first writers at Basketball Prospectus, which launched in October 2007 and became a destination for fans who appreciated a numbers-based approach for their analysis.

“I was a little amazed,” Gasaway said. “I had the feeling that (Oliver's book) would change everything and everyone is immediately going to start talking the way this guy Dean Oliver talks. I thought, ‘I’ve got to start talking like this.’

“It was a great relief to see this other guy named KenPom also online talking this way. ‘OK, I’m not that crazy,’ and we were off and running.”

Going Mainstream

The coach who is often associated with advanced statistics in college basketball is Butler’s Brad Stevens. Stevens told the New York Times two years ago that the first thing he did when the Bulldogs advanced to their first national championship in 2010 was pull up Duke's team page on KenPom.com.

Stevens is kind of a wunderkind of the coaching profession, and there was a perception that the only coaches who used advanced stats were the up-and-comers like him. Larranaga and coaches of his generation are starting to undermine that assumption.

“I like that,” Gasaway said. “Bo Ryan is another example of someone from roughly the same generation who refutes the stereotype you have to be a young or emerging coach to do this stuff. I love the counter examples in both directions. I love to point to more senior coaches who use this stuff and I also love to point to many young coaches who say ‘I don’t need this stuff.’”

Pomeroy's site is no longer the only one that provides college basketball stats beyond the box score. Jeff Haley, a chemical engineer in Cincinnati, Ohio, is another whose curiosity created a website of college basketball data. Haley runs Hoop-Math.com, a site that mines play-by-play data to show how well players score from certain areas of the floor. 

If there’s another revolution to the advanced-stats movement, it’s likely to influence hiring decisions of college basketball coaches, and Stevens is once again out in front of that movement.

This summer, Stevens purchased a scouting report at a summer-league high school game from Drew Cannon, who graduated from Duke in May with a statistics degree.

Cannon got his start in basketball as a high school student by interning with ESPN recruiting analyst Dave Telep. As a sophomore at Duke, Cannon contacted Gasaway and started writing at Basketball Prospectus.

After purchasing the packet from Cannon and talking about his future, Stevens offered Cannon a position at Butler as a graduate assistant.

“Coach Stevens realized I had no idea what I was going to do for the rest of my life, so he helped me delay that decision for two years,” Cannon said.

Stevens shared with Gasaway earlier this season why he trusted Cannon on his staff.

“Brad’s exact words were ‘Drew’s been great, and the reason we took him on was you could just tell how bright he is based on what I read from him at Prospectus and when he worked for Dave Telep,’” Gasaway said.

Cannon keeps track of statistics in practice, which is something Butler did not do before he arrived, and he is also using his background in breaking down the numbers to benefit the Bulldogs.

“Coach Stevens is less of a stats guy than a 'I want every piece of information guy,'” Cannon said. “If you can tell me something that I didn’t already know, I like to know about it. If stats is the way to do it, great. If scouting is the way to do it, great. If talking to some guy at lunch is the way to do it, great.”

Other coaches hiring a stats guru like Cannon could be what’s next.

Many NBA teams already have entire departments dedicated to studying the numbers. Oliver told Slate.com that he estimates 22 to 24 NBA teams employ some type of analytics department. The Memphis Grizzlies made ESPN.com NBA writer John Hollinger its vice president of basketball operations in December. Similar moves have been made by other NBA teams, bringing in the advanced stats guys who got their start blogging.

The college game is playing catch-up to the pros.

“We’re just getting to the point where you can get stats on recruits,” Cannon said. “We’re just now getting to the point where you can start to get play-by-play data for everybody. It’s a lot easier to find the money if you’re all 30 NBA teams than it is all 347 D-1 schools to get that kind of data out for everybody all the time.”

Embracing the Numbers

Gasaway said he was asked earlier this season by Kansas State coach Bruce Weber why his team ranked so low in the computer ratings.

“I thought he was asking why are we so low in KenPom, and come to find out he was really asking why are we so low in the RPI, which is a much different answer,” Gasaway said.

To the advanced stats community, associating a site like KenPom.com with the RPI (Ranking Percentage Index)  is like comparing a chef’s work to a cook’s at McDonald's.

Pomeroy focuses on points per possession, and win-loss records are not as influential.

Getting coaches to think this way can be difficult—wins and loses are what they are judged upon—but they are starting to figure out one greatly influences the other.

“They just want some sort of edge, so they want to know if I've discovered something that might help them statistically,” Pomeroy said. “But all of this stuff is context-dependent.

“Advanced stats can take you to a certain point, but giving anyone a road map to how to win a national title is beyond the point of what advanced statistics can do.”

Gasaway acknowledges that advanced stats are not for everyone, but most fans or coaches are aware of them now and have made up their mind one way or another. 

"I just think it’s a handy tool to be able to call upon," Gasaway said.

That handy little tool has gone from the unknown to an accepted part of the basketball culture.

The numbers tell us who is good and who might not be as great as their record indicates. That's why Pomeroy's data is extremely useful for fans trying to fill out their brackets and coaches trying to advance.

Count on this: The national title winner will likely be a team that fared well all season in the areas Pomeroy measures. Eight of the last nine champions have finished ranked in the top two of his ratings.

Next thing you know, a coach will be thanking a weatherman as he lifts the national title trophy.


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