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NBA 3-Point Attempts and Going For it On 4th Down

In overly simple terms (ignoring things like fouls, rebounds, game theory, etc.), the expected value of a 2-point field goal attempt is the 2-point field goal percentage multiplied by 2, and the expected value of a 3-point field goal attempt is the 3-point field goal percentage multiplied by 3. Here’s a look at the EV for both 2-point and 3-point attempts in every NBA season going back to 1979-1980, courtesy of basketball-reference:

nba

The inflection point came right around 1990; after that, the 3-point shot was associated with a higher expected value, and since ’97-’98, the 3-point shot has about 12% more EV than a 2-point shot. Now, I know just about nothing about the NBA and even less about NBA analytics, but it’s easy to draw a couple of conclusions from this chart. One would be that teams should be taking more 3-pointers, even though “traditional coaches” have not been fans of the 3-point shot. It’s easy to look at this chart and dismiss it, and say that a team shouldn’t take a bunch of 3 pointers just because the math says it makes sense. On the other hand, you have the Golden State Warriors.

Teams have been taking more and more 3-pointers, though, so this isn’t just theory. In this instance, teams are believing the numbers. If you chart the percentage of field goal attempts that are 3-pointers, it looks something like a graph of NFL completion percentage on steroids:

3 pt per

During the ’91-’92 season, only 8.7% of all field goal attempts were three pointers; this past season, that number has more than tripled to 28.5%. Now that teams are taking more 3 pointers, and being successful, it’s easy to say that the math supports it and it makes sense. What is the natural NFL comparison?

I’m not sure, but the first thing that comes to mind for me is going for it on 4th down. For decades, advanced analytics have argued that teams should be going for it more frequently on 4th down. The math supports it, but “traditional coaching” advises against it. At some point, though, I imagine a team will become much more aggressive about going for it on 4th down, it will work, and then everyone will say “duh”.

But I’ll open this up to you: what do you view as the NFL analog to three-pointers?

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