The following is a post I wrote for TeamRankings' Stat Geek Idol. For more information on the competition click here.
Earth shattering revelation: you have to make shots to win basketball games. This is an undeniable truth inherent in the great game Dr. Naismith created.
More controversial statement: you DON’T have to shoot well to win basketball games.
These two statements may seem inconsistent on the surface, but in fact are both true. Not every possession consists of one shot. Empty possessions are ones that end in a turnover before a shot is put up. On the contrary, other possessions consist of several shots via the offensive rebound.
Simply put, the quantity of shots you take is just as important as the quality.
Introducing The WHACKS Rating
About two years ago Ken Pomeroy tweeted, “I request to copyright the phrase ‘gets more whacks at the piñata’ to describe a low FG%/high efficiency offense.” When trying to break a piñata, three medium blows will do the same job as one extremely strong blow.
This is the same with basketball. An 80% shooting team is not going to have success if they turn the ball over 75% of the time. Another extreme example would be a 20% shooting team grabbing 75% of all offensive rebounds. This type of team overcomes bad shooting by getting more “whacks at the piñata”.
The WHACKS Formula: (Team’s OEff)-((100.9/49.0)*(Team’s eFG%))
Explanation: The formula is essentially subtracting a team’s expected Offensive Efficiency (OEff or OEfficiency) based ONLY on shooting from the team’s actual OEfficiency. 100.9 represents the Division One average OEfficiency and 49.0 is the Division One average effective field goal percentage. eFG% is multiplied by the constant to establish the same scale as OEff.
Results (all NCAA Tourney teams):
Southern Mississippi comes out as the team whose offense is best able to overcome bad shooting. However, Southern Mississippi’s defense (126th in the country) probably eliminates them from being a viable threat.
UNC’s High WHACKS Rating Makes Them A Legit Title Threat
Instead, I want to turn the attention to a legitimate title contender: North Carolina. The Tar Heels overcome a very average shooting percentage by being the 9th best turnover team and 8th best offensive rebounding team. Overall, their adjusted OEff of 116.4 puts them at the 12th best offense in the country.
“So UNC gets more whacks at at the piñata, big deal!” Well, they key here is that UNC can survive a bad shooting night in this single elimination tournament. To prove this, I looked at the correlation between eFG% and OEfficiency for the top 5 teams in the country (correlations taken from kenpom.com are r*100).
As suspected, UNC’s OEfficiency was LESS dependent on eFG% than any of the other top 5 teams in the country. It’s highly probably UNC will have a bad shooting night at some point in the near future. However, by taking care of the basketball and crashing the glass they will be able to overcome a bad shooting night better than other teams.
Here is a crazy example of just how “lucky” shooting can be. It seems fairly intuitive that rebounding and turnovers are going to have less variation from game to game. By relying less on result of shots and more on quantity of shots, UNC increases their chances of PLAYING LIKE UNC on any given night. If UNC plays like UNC they should be considered a top Final Four candidate and beyond.