Making Sense of NBA Stats: NBA Foul Trouble

Our latest foray into making sense of NBA stats will have us look at foul trouble in the NBA. It can be very narrative filled with people throwing out things like “he's defending Blake Griffin, so he'll definitely be in foul trouble. Foul trouble, however, is much more highly correlated to the player committing the foul (0.78) than it is to the player being fouled (0.63). One example of an outlier to that is James Harden, as he draws more fouls than anyone in the league on a nightly basis.

Foul Trouble Causes Inconsistency

In many cases players are labelled inconsistent because of the inconsistency of their fantasy production, but it's not necessarily a reflection of their play if it's foul trouble related. For instance, before his “retirement" Larry Sanders was one of the most consistently good rim protectors in the NBA, but his fantasy production was a roller coaster due to his propensity to get in foul trouble. He's a very extreme example, but also one well worth looking at. Below we have a graph of the most fouls per 36 minutes in the NBA, among players who play at least 18 minutes per game.

As you can see, there are two players who average actually fouling out in each 36 minute segment, Sanders and Jusuf Nurkic. Nurkic is another player who has a really bad reputation as an inconsistent player, but it's almost entirely tied to his foul trouble. Predicting big games from him becomes more luck than with other players in the NBA, because you can play him in the best of matchups when he's expected to play a full complement of minutes and get a complete dud out of him due to foul trouble. As you can see with the rest of the players on this list, it's a who's who of guys who have let us down in great situations over the course of the season.

Foul Trouble Can be Relegated to Big Men

As you saw with the above list, there are zero guards on it. Guards simply don't foul as much as big men, because most fouls occur around the basket, where the big men patrol. While there are a plethora of big men above 4 fouls per 36 minutes, there are very few guards, three officially to be exact. Let's take a look at those below.

The guy who tops this list, Henry Walker, is officially a shooting guard, but he's played 73% of his minutes at power forward this season for a depleted Miami team. We can basically throw him out. The rest of the list is comprised of two types of guards, fantastic defenders and awful defenders. The reason for this is really good defenders, like Patrick Beverley and Tony Allen, hound the offensive players because it's their main focus and they aren't worried about fouling. While poor defenders, like Aaron Brooks and Jeremy Lin, have to use their hands more on defense because they can't stay in front of their opposition without fouling.

Referee Information

Knowing who is refereeing a game can be an advantage as well. Each referee is human and has his or her own tendencies just as players do, so ignoring a large part of the NBA game makes little sense. Referees, of course, are all supposed to call the game the same way, but it's simply not possible. For instance, Nick Buchert calls 10 more fouls per game than the 40th highest foul calling referee, 50 fouls called per game compared to 40. This is a huge difference if you're looking to play someone like Nurkic, who we mentioned above, and is worth investigating should you be interested in taking a risk on a foul prone player that night.