Mapping the NBA: Inside Out

The most efficient shot attempt in basketball is a pair of free throws (unless your name is Chuck Hayes). The league as a whole shoots 75 percent from the line, which means an average trip to the charity stripe will net a point and a half. But you can't exactly draw up a play to get free throws, try as Dwyane Wade might. Free throws are more circumstance than plan, though certain players (LeBron James, Kevin Martin) obviously have styles tailored toward drawing fouls.

You can decide what field goals you'll attempt, though. Unsurprisingly, distance from the hoop matters greatly in a shot's efficiency. Shots taken at the rim -- dunks, lay-ups, putbacks, tips and other assorted very short attempts -- are the most efficient attempts from the floor, with the league as a whole hitting 60 percent of its at-rim attempts this season. The further you move out, the lower the average conversion rate. Attempts between 5-10 feet fall at a 45 percent clip this season. From 10 to 15 feet, the league field goal percentage is a shade above 40 percent. From 15 feet to the three-point line, the conversion rate is 39 percent. On threes, the league is currently shooting just below 35 percent.

But wait! Threes count for an extra point, and that can't be dismissed. This is why we like to use effective field goal percentage when talking about floor efficiency: it counts made threes as 1.5 made field goals, owing to the fact that a made three-pointer is the scoring equivalent of one-and-a-half made two-pointers. When you adjust for that, the league's efficiency on threes is bumped to 52 percent, making it the second most efficienct shot from the floor.

And it's really quite a difference between the two efficient locations (60 percent at the rim and 52 percent from deep) and the other slots (45, 40 and 39 percent, respectively). If you split 20 attempts evenly between the deep paint and three-point territory, you'd be expected to score 22.4 points (assuming league average efficiency). If you instead took 10 short jumpers, five mid-range jumpers and five long two-point jumpers, you'd be expected to score only 17 points. Teams should clearly prefer shots at the rim and from beyond the arc as opposed to all other locations. It's not always that easy -- every team tries to get dunks and lay-ups, but some players are far more adept at getting them (for themselves and teammates). But clearly, some teams settle for two-point jumpers too frequently, given the efficiency spread.

So which teams take the greater share of their attempts at the rim? From downtown? Do any teams get tons of shots in both locations?



The x axis shows each team's percentage of attempts taken at the rim, with more frequent close shooters to the right. The y axis represents the same spread with percentage of attempts taken from behind the three-point arc, with the most frequent three-ball shooters (Orlando, New York) at the top.

Only two teams find themselves in a position in which they take more shots at the rim than league average and more threes than league average: Houston and Sacramento. New York (the second most frequent deep gunners) and Charlotte (the most frequent shooters at the rim ... by a wide margin [!]) come close. It's no surprise that the Rockets have a "smarter" shot selection on paper than other teams -- the Houston front office is driven by data, and shot data is among the most valuable available. The Kings are a bit more interesting, if only because last season the team took plenty of threes but was roughly the worst squad in the paint. Tyreke Evans, who gets the rim frequently, has changed that dramatically.

Interestingly enough, Cleveland and the Lakers have basically identical at-the-rim and three-point frequency profiles. Oddly, though, the Cavaliers are far more efficient in both categories: 64 percent to L.A.'s 60 percent at the rim, and 63 percent (eFG) to L.A's 50 percent from deep. Cleveland happens to be really bad (comparatively) at converting everything in between, though.

Do any teams have woeful shot selections based on location? Only one team takes fewer shots near the rim than Washington, yet the Wizards sit in the bottom dozen in three-pointer attempt frequency. What gives? Blame it on a set of players (Caron Butler, Antawn Jamison and Andray Blatche, to name three) more likely to fire mid-range twos than to shoot threes or get to the rim. Flip Saunders has cursed Washington's shot selection repeatedly, and that surely has more to do with the level of contention those shots receive from opponents than location, but the team's shot selection profile based on location sure isn't showing the offense is set up for success. A talent change will be needed for the profile to be fixed (though obviously actual offensive performance is more important than the shot selection profile).

This is the point at which I ask Chicago if they miss Ben Gordon, ask Minnesota is it is in the market for a shooting guard or three, and tell Milwaukee to get Andrew Bogut the ball more often.

(Three cheers for HoopData.com, from which all data above comes.)