A.P. Hoops: Putting it All on the Line

Brandon Costner's L.A. D-Fenders team has been one of the best in the NBA D-League this year at getting its points the easy way.
Chris Graythen/Getty Images

We have reached a big day: the last of the “Four Factors of Basketball Success.”

Thus far we have discussed shooting efficiency (eFG%), rebounding (REB%) and ball control (TORatio). Today we’ll tackle the final factor: Free Throws.

Perhaps you’ve already heard that free throws matter. That teams and players that get to the free throw line typically do better than those who don’t. If you fall into this category – you are correct. The reason is simple: possessions ending in two free throws typically result in more points than possessions that don’t.

The mathematical proof of this a tad trickier that the concept itself, but still rather manageable. The NBA D-League as a whole averages 103.3 points per 100 possessions (a value called Offensive Rating, which we’ll discuss later this year). Across the whole league, composite free throw percentage stands at 72 percent.

That means, for every pair of free throws taken, we’d expect roughly 1.4 points to be scored (.72 x 2 FTA = 1.4). Therefore, over 100 possessions ending with two free throw attempts, we’d expect 140 points to be scored – almost 37 points more (and 36.7 percent higher) than the 103.3 number we remember as the league’s offensive rating.

Now that we understand the importance of free throws, let’s take a look at how free throw effectiveness is measured. Free throw rate can be measured two different ways depending on your preference. The first measurement gauges the number of free throws taken per field goal attempt...and it's really simple. This is done the following way:

Voila. Free throws over field goals.

However, measuring free throw attempts does not account for good or poor free throw shooting. In other words, just getting to the line ain’t enough.

For example, Charles Garcia is tied for the second-most free throw attempts in the NBA D-League this year, with 97, but has only converted 54.6 percent of them. Since Garcia is a good scorer otherwise, it is actually beneficial for opposing defenses to send him to the free throw line, which would ultimately inflate and skew his free throw rate. (Dwight Howard creates a similar problem on the NBA side of things).

It is for this reason that a better measure of free throw effectiveness charts free throws made per field goal attempt. The calculation is as follows:

The better a player or team is at free-throw shooting, the closer their FTA and FTM rates will be. Now let’s take a look at teams with the best FTA rate and FTM rate in the NBA D-League. You will notice that poor free-throw shooting teams such as the Canton Charge and Tulsa 66ers have a comparatively higher FTA rate than FTM rate.