With this wealth of data, the hard part is figuring out how to apply it when building a team and formulating game plans. Per Dean Oliver’s research, the premise is that offensive and defensive eFG% has the most impact on winning. The next most influential stats are TO%, OR% and Free Throw rate. We have heard coaches at all levels talk about taking good shots, eliminating easy shots for the opponent, not turning it over and rebounding the ball. In a nutshell that’s what these stats measure, but in a more intricate and detailed way.
In evaluating the Four Factors for any team, we must remember that being good in these areas does not guarantee wins. It can however be an excellent predictor of success. In addition, while the overall rank of each individual statistic is important, the differential between offensive and defensive numbers can be more indicative of success. We can’t look just at eFG% offense without also comparing that to eFG% defense.
When evaluating the eFG% stats and differential of NCAA teams here are some facts:
- 28 of the top 68 offensive eFG% teams are in the NCAA tournament (41.2%)
- 30 of the top 68 defensive eFG% teams are in the NCAA tournament (44.1%)
- 39 of the top 68 differential teams (off eFG% - def eFG%) are in the NCAA tournament (57.4%)
- 6 of the 68 team NCAA field had a negative eFG% differential
The fact that jumped out to me was the last one in regards to the NCAA field only having six teams with negative eFG% in the tournament. When you look deeper, it gets even more interesting. The teams in the negative were Colorado, Providence, Milwaukee, Wofford, Mount St. Mary’s and Cal Poly. Out of those 6 only two, Colorado & Providence (bubble team), would have made the tournament without being an automatic qualifier. The interesting statistic for both of those schools is that they both have very positive OR% differential: Colorado +7.9 and Providence +4.7. One could argue that they make up for the eFG% disparity by consistently winning the battle of the back boards.
Out of curiosity I also looked back at the NCAA fields for 2013 and 2012. In the NCAA field for 2013, only Illinois and James Madison had negative eFG% differentials. While both of these teams had slight negatives in rebounding differential, they both had positive TO% differentials: Illinois +4.3 and James Madison +3.9. Back in 2012, the field contained six teams with negative eFG%: Southern Miss, West Virginia, Loyola MD, Detroit, Lamar and W Kentucky. Only two of these teams, Southern Miss and West Virginia, were at large bids. Similar to 2014 they both have high positive OR% differentials: Southern Miss +7.5 and West Virginia +10.5.
So in conclusion, eFG% differential does not guarantee enough success to make the NCAA field, it is highly unlikely to have a negative differential and make it in. If your team doesn’t consistently win the eFG% stat, you better be able to rebound at a high rate or take care of the ball. Regardless of the stats, you can always make a run in the conference tournament to go dancing!