Pac-12 Basketball: Introducing Individual Efficiency Margin

Identifying statistics and analytics that aren’t influenced by outside factors in sports is no easy task.

I have recently created a formula, however, that filters out a given team’s strength in order to determine how much true value a player holds. I call it Individual Efficiency Margin.

For those who aren’t familiar with tempo-free stats, basketball has now been boiled down to possession-by-possession stats to better understand the game, most notably showcased by the highly popularized efficiency ratings - complex measures of points scored/allowed per 100 possessions. As far as wins and losses are concerned, the stat is fairly simple: if a team’s offensive efficiency rating is higher than its defensive rating, the team will always win. (You always want to score more points per possession than you allow.)

Two noteworthy names on the basketball analytics Mount Rushmore, Dean Oliver and Ken Pomeroy, have found great value in individual efficiency ratings and “net” ratings, which are computed simply by subtracting offensive rating by defensive rating. (UCLA’s Lonzo Ball has recorded an offensive rating of 136.6 and defensive rating of 98.1 through 11 games this season, giving the freshman a +38.5 net rating.)

Using each Pac-12 player’s net efficiency rating, their team’s ratings, and average ratings for the D-1 this season, I compiled a complete list of efficiency margin ratings that are not specific to any given team. This means that net efficiency ratings will not be impacted by a team’s strength, so a UCLA and Oregon State player will be weighted equally.

Minute percentage (a measure of how many possible minutes a player appears on the floor) also plays the role of filtering out players that have skyrocketed up rankings due to small sample size. The entire list of Pac-12 individual efficiency margins is attached below:

Washington State forward Josh Hawkinson (who has single-handedly held together the Cougar program the past three seasons) has a 112.8/95.8 efficiency slash line through 10 games, which may seem like a decent mark to some, but is fairly significant when you consider the strength of his WSU team. Washington State is one of very few power conference teams in the country with a negative efficiency margin in conference play, further showing Hawkinson’s worth to the Cougars.

Drew Eubanks and Markelle Fultz, two players that do not rank in the top 15 in the Pac-12 in offensive or defensive efficiency, are other examples of quality players on weak teams that continue to log strong efficiency margins.

Conversely, UCLA’s T.J. Leaf leads the league in offensive efficiency with a blistering 141.6 rating, but due to the Bruins’ historic offensive start this season, he doesn’t carry nearly as much relative value to his team as players like Hawkinson, Eubanks or Fultz.

These numbers will constantly fluctuate as the season progresses and efficiency numbers rebalance, but non-team specific efficiency margins should be something on every basketball stat geek’s radar. Look for more on this subject in the near future.