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Official Rock Chalk Talk Advanced Stats Primer (2013-14 Edition)

A brief look at some of the more advanced metrics around college hoops

Denny Medley-USA TODAY Sports

As far as serious topics go, advanced stats are pretty low on the list. It's not like I'm writing about a new way to cure cancer or breaking down a serious legal issue. But this is a site that at least attempts to be serious about a game (or games) for some portion of the time, so the (mock) serious headline will have to stick.

"Advanced" stats is kind of a misnomer, as there really isn't a lot of complex math involved here. Just a little thinking outside the box. And this stuff isn't really that new either, as former Jayhawk Dean Smith was doing a lot of this stuff back in the 1960s. Still, I can't help but cringe when a writer/commentator/fan/coach/whatever refers to points per game when describing a team having a good or bad offense, or using number of rebounds to determine who outrebounded the other team.

Below we'll take a look at why possessions are key, as well as the four factors, and explain their importance and attempt to tidy it up in a little bow for everyone. But if you want to stop here just remember this one point: think in possessions, not games.

You down with PPP (yeah you know me)

Think of two baseball teams. Let's say the Twins and the Royals. The Twins score 4 runs per game whereas the Royals score 6 runs per game. Pretty obvious the Royals have a better offense, right? But what if the Twins only had 3 innings in which to score their runs, while the Royals had their full 9. It becomes just as obvious that would make the Twins the better offense.

Awkward cross-sport metaphor aside, let's use a basketball analogy. Wisconsin scored 64 points per game in 2012, good for 261st in the country. Meanwhile, Kansas scored 75 points per game, good for 36th. Pretty obvious Kansas had the better offense right? Wrong. Wisconsin was one of the slowest teams in the country that year, having just 58.5 possessions per game, whereas Kansas was much closer to the norm, having around 67 possessions per game. It's unfair to ding a team's offense (or credit their defense) because they have a lack of opportunities to score, either by design or opponent design. Every team in the country has an equal opportunity to score on a per possession basis (either you do or  you don't, obviously) but the number of opportunities teams have to score per game varies wildly. Judging teams by how they do in those common possessions is much more valuable than how they do in a per game basis.

Four Factors


Effective field goal percentage, or eFG, is really simple. It merely gives credit to guys for making three pointers, which is obviously more valuable than making two pointers. This way people don't get sucked into the trap of thinking a guy like Tarik Black, who will live inside the paint, is a better/more valuable shooter than say Andrew White, who is going to make a lot of threes.

Turnover percentage

Much in the same vein as points per game, discussing how well teams take care of the ball by turnovers per game is a bit midguided. Using number of turnovers divided by how many possessions there are in a game gives a far more accurate picture of who is actually best at taking care of the ball, as explained above.

Rebounding percentage

After the PPP stuff, not using rebounding margin is probably the second most important point to make here. To do so, I'll use a post I wrote a couple years ago:

rebounding margin is the most flawed stat out there. To illustrate this, let’s take a look at the Baylor Bears. Topical, since they played just last night. Baylor currently leads the country in rebounding margin, at +11.4 per game. But a closer look reveals why. Baylor forces turnovers on just 17.2% of their defensive possessions, good for 324th overall in the country. This means that the opposition has many more shots to shoot, which naturally results in a lot more available defensive rebounds. And, since defensive rebounds are easier to grab than offensive ones, it artificially inflates Baylor’s numbers. In fact, Baylor is only 67th in defensive rebounding when calculating the percentage of opponents’ misses that they grab, which is the most important.

As Beadlemania hero John Gasaway posits, rebounding is really two skills: offensive and defensive rebounding. Defensive rebounding is the best way to compare how good two different teams are on the glass, because everyone tries equally hard to get defensive rebounds.

Offensive rebounds, however, are another story. Hard as it may be to believe, some teams don’t really try to get offensive rebounds. Take Colorado under Jeff Bzdelik. The Buffs are far more concerned with getting back on defense, usually leaving only one guy down low to try to grab an offensive board. This is a result of wanting to limit possessions. To wit, Colorado is 333rd in offensive rebounding this year and was 342nd last year. Staying in the Big 12, Kansas State still leads the country in offensive rebounding, at 43.5% Thus, rebounding margin can penalize teams that don’t try to go after offensive rebounds with the same vigor as other teams. We can argue the merits of this strategy another day, but the fact remains these teams are penalized for no reason in rebounding margin.

I don’t think I even need to tell you the last one: pace. Obviously teams that play fast are going to take more shots, which will result in more misses, which will result in more rebounds available. Take the Texas Longhorns. Texas is 6th in rebounding margin at +6.2 per game, and although they do well on the offensive glass, they’re merely adequate on the defensive glass, where more rebounds are available. This high rebounding margin is due to the fact that they are the 5th fastest team in the country. Northern Iowa is 104th in rebounding margin at +2.8 per game. However, they are much better than Texas on the defensive glass, only allowing the opponents to rebound 27.5% of their misses. This is because Northern Iowa plays at the 343rd fastest pace in the country at 60.9 possessions per game.

So there you go. How to be a good team in rebounding margin: play fast, don’t force turnovers, miss quite a few of your shots. I don’t want to give that team credit for much of anything, do you?


This, as you might expect, is merely looking at who gets to the line the most in a different way. Rather than referring to it as such and such team goes to the line 28 times per game, it's better to go about it as a function of number of the number of field goal attempts they have, in order to better incorporate pace.

If you skipped to the end (or already know all this) just remember this: pace is important. Determine who is the best by looking at per possession rather than per game, never ever ever cite rebounding margin, and give people extra credit for making threes.