Statistic: PER (Player Efficieny Rating)
What is it?
- PER, created by John Hollinger of ESPN, is a single numeric rating of a player’s per minute production.
- PER takes into positive contributions (Points, Free Throws, Rebounds, Assists) and negative contributions (Turnovers, Missed Shots, Personal Fouls).
- Hollinger adjusts his PER formulas each season so that a PER score of 15.00 represents the league average.
Why should I be interested?
“What PER can do, however, is summarize a player’s statistical accomplishments in a single number. That allows us to unify the disparate data on each player we try to track in our heads (e.g., Corey Maggette: free-throw machine, good rebounder, decent shooter, poor passer, etc.) so that we can move on to evaluating what might be missing from the stats.” – John Hollinger
- The quote above by Hollinger captures the crux of PER. It gives us a single number, which represents all of a player’s statistical contributions.
- Since PER is a per minute rating it allows us to make reasonably fair comparisons between players who have vastly different roles on their teams. For example: in the 2009 – 2010 NBA season Elton Brand had a PER of 15.7 and Mareese Speights had a PER of 17.6. Brand played 30.4 minutes per game and Speights played only 16.4. Brand’s per game numbers will look much better because he played more minutes. PER shows us that Speights was actually much more effective during his time on the floor.
- Since the league average is set to 15.00 each season it lets you judge how far above or below average a player’s overall contributions are.
Why should I be skeptical?
- With a comprehensive rating like PER, you get general information about the quality of a player’s production but not much in the way of specifics. For example PER can tell you that Mareese Speights was an above average player in his minutes on the court, but it doesn’t tell you if he is a strong rebounder, or a poor free throw shooter, etc.
- PER does not do a good job of rating the production of strong defensive players who don’t generate many steals or blocks. For example, Bruce Bowen is widely viewed as one of the best perimeter defenders of the last decade. However, he didn’t create a lot of steals or blocks and never finished a season with a PER higher than 10.00. Therefore, PER misses most of his very effective defensive contributions.
Where can I find it?
- What is PER? – A more detailed explanation from Hollinger himself.
- PER was created by John Hollinger, and much of his work at ESPN.com uses PER for comparisons, analysis, rankings and predictions. You can check out his ESPN archive here.
- PER has become more mainstrean, and can be found on the player pages or team breakdowns at many basketball statistic websites. Some of my favorites:
Draftexpress NBA Stats