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Layups: Custom Pythagorean Exponents

Posted by Neil Paine on May 19, 2009

Here's an interesting article... You've heard of the pythagenport floating exponent in baseball, right? Zach Fein of has come up with something similar for the NBA. The standard 14 that we use is very good, but you can get slightly better results from this formula:

Exp = sqrt(Poss.) / log(Poss.) x 0.75 - 2.8

Where "Poss." is possessions, as defined by our glossary. The overall increase in accuracy is small, but I think it's still a very worthwhile pursuit to find better exponents for the pythagorean method.

Oh, and can we call this the "Pythagenfein" formula from now on?


2 Responses to “Layups: Custom Pythagorean Exponents”

  1. Justin Kubatko Says:

    All of that extra work for a less than 1% decrease in the RMSE? That doesn't seem worth it to me.

  2. Neil Paine Says:

    Probably not, and I'm still using 14 in the future. But I've always wondered about a floating exponent for basketball, and now we have one.