This project was similar to the last project, but this is looking at shot zone rather than exact location in feet. For the data I used, there are 7 different shot zones: restricted area, in the paint (non-restricted area), mid-range, left corner 3, right corner 3, above the break 3, and beyond half court (backcourt). I was interested to look at how much a shot is worth at each zone, and then think about how that could apply to how we think about and watch NBA basketball. The data used is shot data in the NBA from 2015-2020. The code for the project can be found at this link:
Here is the chart output from the code:
The chart above shows the average value of a shot (blue bar), average shooting percentage (red line), and overall average value of any given shot (gray dotted line). This image mirrors the results of my last project, but it also puts into perspective even more how valuable shots near the rim are, and how much less valuable shots just outside the rim are. The restricted area is only four feet in size in every direction around the rim. According to the data presented here, a player should not shoot the ball from outside of that area unless they are outside the 3-point line. I will say this again: analytics people aren't obsessed with 3's, and no "analytics person" would ever tell a player to pass up a layup for a three.
I also think it is interesting to look at the difference between the value of a corner three vs. an above the break three. There are a few reasons for why a corner three may be more valuable outside of what conventional wisdom might say. The obvious reason for why a corner three is worth more is because it is closer in distance. The closer you are to the rim, the easier the shot. That seems obvious, but the difference between a 22-foot shot and a 24-foot shot shouldn't be that high. As you might have seen in my last project, the shooting percentages generally plateau after about five feet. Here is an updated version of that chart to illustrate that point:
So, the reason I think corner threes are actually so valuable is because of shot quality. Think about what types of shots a normal corner three is. Generally, it is going to be a catch and shoot. You rarely shoot off of movement, off the dribble, or in a late clock heave situation from the corner. I would imagine the average quality of a look from an above the break three is simply much lower. Further research would have to be done to figure this out. This doesn't mean that teams shouldn't be chasing corner threes because they absolutely should be. If you are the slightest bit more likely to make a shot because you are 1-2 feet closer, then you should take that opportunity. That is part of the reason why I love hammer plays so much: they are the best way to get a look in the corner.
Understanding these basic charts and values is not only important to an offense, but it is vitally important to a defense. When building a defensive scheme, you need to consider these types of charts. The teams that gave up the most threes defensively last season were the Raptors, Heat, and Bucks. Despite that, those teams ranked 2nd, 9th, and 1st in terms of overall defense, respectively. They did this by understanding shots at the rim are even more valuable than shots from three. Those three teams were all top-6 in terms of allowing shots at the rim, and they built their defenses on the premise of giving up open threes to prevent contested layups. That is just smart coaching and understanding the numbers.
Below is the data for each shot zone (shot % and value):
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