A: The most concise explanation I have is it's a rating of a player's per minute statistical effectiveness. So basically, you give them points for all the good stuff, subtract points for all the bad stuff and out comes a rating. It's a bit more complicated than that, but in a nutshell that's what it is.
Q: How did you invent this statistical rating?
A: It was a lot of trial and error. I've always been kind of a stat head. I was really influenced by Bill James' books when I was a kid. I had started thinking about how I could apply it to basketball. I worked on PER for a long time just by myself just on Excel spreadsheets. And then when the Internet came along, I started putting my ratings online. This was in 1996. Even from there, I think it was probably three or four years before it got to the point where it is now.