What actually does matter in terms of winning games?
To answer this, we first need to get to the more important question: what matters for winning games period, and what matters for overall efficiency, both raw and adjusted?
This offseason, I had the opportunity to dive into both questions for…well, fun? Before we go too deep, it’s important to know that when Dean Oliver originally created the Four Factors in the early 2000s, his studies envisioned the Efficiency Equation as breaking down in a manner similar to this:
- eFG%: 40% of overall efficiency
- TO%: 25%
- OREB%: 20%
- FTR: 15%
The good news for Mr. Oliver, a personal hero, is that the actual ranking of these four stats still holds true. Effective Field Goal Percentage is still the most important stat to both winning and overall efficiency in college basketball, followed in order by TO%, OREB%, and FTR. The less-good news, I guess, is that the actual shares of these four stats needs a serious realignment in modern college basketball. Based on my research, the actual breakdown of the Four Factors in the 2019-20 and 2020-21 seasons goes more like this:
- eFG%: 50% of raw efficiency; 53% of opponent-adjusted efficiency
- TO%: 25% raw; 24% opponent-adjusted
- OREB%: 19% raw; 17% opponent-adjusted
- FTR: 6% raw; 6% opponent-adjusted
The only piece that has remained almost entirely unchanged in the 17 years since Oliver published his work are turnovers, which have consistently remained 25% of the total pie. However, shooting is more important than it’s ever been, with one’s Free Throw Rate – the share of free throw attempts versus field goal attempts – less important than ever. It barely scratches its way to 6% of the pie in both raw and adjusted efficiency.
When it came to actual wins and losses, eFG% reigns even more supreme. Teams that win the eFG% battle win 81.5% of the time, which is a far cry from OREB% (62.1%), FTR (61.1%), and TO% (59.9%). Moreover, in games where teams won only one of the Four Factors, nothing came close to eFG%’s prominence in determining the final result:
- Only eFG%: 36.3% win rate
- Only TO%: 7.9% win rate
- Only OREB%: 6.3% win rate
- Only FTR: 1.5% win rate
If you aren’t winning the shooting battle consistently, you aren’t going to win many games. If you win the two most important factors, your odds of losing are pretty darn small. In 2020-21, 1,708 teams won both the eFG% and the TO% battle in a given game. Those teams went 1,602-106 (93.8%). No other combination of stats produced a win rate that extreme.
Is the recipe for close games any different?
Here’s where the fun begins. Keep the all-game figures shown above in your head for the next few paragraphs, if you don’t mind. Based on our 3,079-game sample size, here’s how the Four Factors correlated to efficiency, both raw and opponent-adjusted, in only close games:
- eFG%: 57% of raw efficiency; 61% of opponent-adjusted efficiency
- TO%: 29% raw; 26% opponent-adjusted
- OREB%: 11% raw; 10% opponent-adjusted
- FTR: 3% raw; 3% opponent-adjusted
Again, in an average setting, nothing mattered more to the final result than winning the eFG% battle. Turnovers grew in importance just a tad, but what stood out most was how little rebounding seemed to matter. It only represented 11% of the overall pie even in the best light, which was quite disappointing as someone who does get quite excited over a quality offensive rebound. There wasn’t much of a serious difference in terms of home/away splits, either; road teams that won the OREB% battle won 50.6% of the time, while home teams were a hair better at 52.1%.
If we stop here, we can say the following: shooting is still king, turnovers are of fair importance, and rebounds are very overrated. However, there’s the somewhat important matter of determining wins and losses, not just efficiency. After all, no one cares what percentage of your pie was three-point shooting or stolen possessions as long as you post the win at the end of the day. When I ran these numbers the first time, the results were honestly a mild surprise:
- Won FTR: 62.9% win rate
- Won eFG%: 62.5%
- Won OREB%: 51.8%
- Won TO%: 49%
This puts the turnover battle in an almost entirely meaningless light, at least at face value. What it also does is show the importance of officiating. Free Throw Rate suddenly became the most important stat of all with the highest correlation to winning close games of any of the Four Factors. This is pretty funny, considering how unimportant it seems to be in games decided by 7+ points. Of course, if you’re a fan of a team that plays in a lot of close games, it makes a lot of sense. Free throw attempts and foul counts take on an elevated importance when you’re playing in a tight game, simply because the average pair of free throws in college basketball is worth around 1.4 points per possession. If you get more of those attempts than the opponent in a game that’s otherwise even, you’re probably more likely to win.
…also, it really helps to be at home.
- Road teams that won FTR: 56.9% win rate
- Home teams that won FTR: 67.8% win rate
Along with this, no combination was a better predictor of a future win in close games than winning both eFG% and FTR, which resulted in a 75.3% win rate.
Here’s what makes this so hard to take meaningful action on: Free Throw Rate is still the least-important Four Factor to efficiency (which is more stable than a simple W-L record) in both blowouts and nail-biters. Considering that still focusing on eFG% + TO% (66.6% win rate) or eFG% + OREB% (69.5%) would’ve produced a pretty nice base of results anyway, you shouldn’t start overhauling your offensive system to draw 30 fouls every single game. Simply put, not every game you play will be a close one.
So, yes: the recipe for actually winning close games is a bit different than it is for everything else. However, a good bit of it can be explained by where you’re playing, and you should still be aiming to out-shoot your opponent anyway.
NEXT PAGE: Miscellaneous other research areas you may care for, including a Tennessee-specific look