Offensive Efficiency Rating (sometimes abbreviated ORtg or OEff or simply Rating or Efficiency) is based on the work of Dean Oliver, NBA consultant and author of Basketball on Paper. In my estimation, it is mathematically more sound than Hollinger’s PER, and the number actually represents something (points produced per 100 possessions), as opposed to being a comparison to league average.
The table is initially sorted by Offensive Efficiency Rating. I also included my schedule-adjusted Offensive Rating, Individual Scoring Possessions, Total Possessions, and Points Produced (the three of which comprise the overall rating), Floor Percentage (ISP/ITP), Efficiency Contribution (based on the player’s contribution to team Efficiency Rating), and EC divided by total possessions.
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Can you send me the formula for calculating ORtg for college players? Can you calculate using only box score data?
If you really have an interest in using the formula, I recommend purchasing Dean Oliver’s Basketball on Paper book—from what I remember, it’s too complex to simply post here. Depending on the level of school, a college box score is enough to calculate it. Most D-I and D-II schools would be easy enough.
It’s been several years since I really did a lot of heavy basketball analysis, so the book is really your best resource for this sort of thing. The basic formula can also be found in the glossary here, but that probably won’t get you very far.