APBRmetrics

Reading through, it doesn't seem to me that the selection bias they mention is right. If you use the four-coins example, assuming that each of the permutations happens once, there are a total of 22 coin flips after a head, and 11 of those flips are heads, just what is expected. The bias the authors ...

Free Throw Rate itself means FTA/FGA. I think that is the one generally accpected in the Four Factors. (Hoopdata for example)
There are some who use FT/FGA, but I think that would be combining two skills into one stat, the ability to get to foul line and the ability to knock them down.

The Four Factors have long been established as the factors behind both offensive and defensive efficiency, but I have yet to see any study on their relative importance. (maybe it's just me) So I ran some regression of several factors with efficiency for teams from 1996-1997 to 2012-2013 (both offens...