An article published in the New York Times last week began as follows:
For Free Throws, 50 Years of Practice Is No Help
by John Branch
CEDAR CITY, Utah –
Yes, an article from the New York Times was filed from Cedar City, Utah.
Now Cedar City is home to a number of wonderful things. There is
- Southern Utah University, a school that I think deserves far more attention than it receives (it’s really a very good school, and no, I am not just saying this).
- the Utah Shakespearean Festival, which won a Tony Award in 2000 (yes, it’s quite good).
- within a very short drive, a number of national parks including Bryce Canyon, Cedar Breaks, and Zion National Park.
Although all of this deserves more national attention, the New York Times ignored it all. No, what John Branch wanted to focus upon was free throws.
Coming to Utah to Discuss Free Throws?
And why would Branch come to Cedar City to discuss free throws? It turns out that the Southern Utah Thunderbirds lead the NCAA in free throw percentage.
And that leads us to ask…. why would the New York Times send someone to Cedar City to cover the Thunderbirds ability to hit shots from the charity stripe? Although the story involved a trip to Cedar City, the focus was on the following:
- Free throw percentage is remarkably consistent across time. An average college player hits 69% of his free throws. Players in the NBA and WNBA hit about 75%. With respect to the NBA and NCAA, these averages have persisted since at least the 1960s.
- It’s argued in the article that coaches can impact free throw percentage. At least, that is a reason offered for the superior free throw shooting observed at Southern Utah.
- Most coaches, though, do not focus on free throw shooting (hence performance does not change). And coaches ignore free throw shooting (again, according to the article) because other aspects of the game are considered more important. After all, as the article note:
“There is little correlation between free-throw percentages and winning percentages. Only one of the 25 best shooting teams, No. 2 North Carolina, is also in the latest Associated Press top 25 rankings. Southern Utah has a losing record. That is why, despite accounting for more than 20 percent of scoring in men’s college basketball and just below 20 percent in the N.B.A., free throws receive a fraction of the attention from coaches, players and fans.”
The Importance of Free Throw Shooting
If we look at the NBA we can see evidence for why coaches should ignore free throw shooting. From 1977-78 to 2007-08 the correlation between a team’s free throw percentage and team winning percentage is only 0.18. In other words, free throw percentage explains only 3% of team wins [correlation is r, explanatory power is r2]. Given these numbers it’s clear that teams should just ignore free throw percentage.
Of course, there’s a problem with these numbers. Our simple model of winning percentage supposes that wins are only explained by free throw percentage. In other words, we didn’t include any other explanatory variable. And since other factors definitely matter, our model is mis-specified. In simpler terms, because we didn’t consider any other factor that impacts wins, our simple model really really won’t tell us the actual link between winning percentage and free throw percentage.
When we do specify the model for winning percentage properly we do see that free throw percentage does matter quite a bit. And to see how much it matters, consider the productivity of players who struggle at the free throw line.
Shaq and Superman
Perhaps the most famous poor performer at the line is Shaquille O’Neal. Shaq entered the league in 1992-93. Across the next 16 seasons (ending with the 2007-08 campaign), O’Neal posted a 0.307 WP48. Certainly this is an excellent mark (average is 0.100). But relative to the following sample of all-time greats, Shaq comes up a bit short:
- Magic Johnson: 0.429 Career WP48
- Larry Bird: 0.365 Career WP48
- Michael Jordan before his first retirement: 0.390 Career WP48
- Michal Jordan before his second retirement: 0.362 Career WP48
- Michael Jordan before his third retirement: 0.332 Career WP48
- David Robinson: 0.350 Career WP48
What do these numbers tell us? Well, MJ – if he wanted to maximize his career WP48 (not that this was his motivation) – should have limited his retirements. But more important to our story, Shaq comes up short relative to these all-time greats.
Of course, Shaq comes up short because he has trouble hitting free throws. For his career he only hit 52.4% of his free throws. What if Shaq hit at a 75% rate? Across his career he attempted 10,376 free throw attempts and made 5,441. If he was average from the charity stripe, though, he would have hit 2,361 more free throws. With each additional point worth 0.033 wins (which we know from our complete model of wins), if Shaq scored 2,361 more points across his career – with no change in free throw attempts or field goal attempts – O’Neal would have produced 76.9 additional wins. And this means Shaq’s career WP48 would be 0.405 prior to the 2008-09 season. In sum, if Shaq just hit his free throws, his productivity would have compared more favorably to a few more of the all-time greats.
A similar story could be told about Dwight Howard in 2008-09. Currently Howard is posting the following numbers (prior to Sunday’s game):
- 60.4% free throw percentage
- 18.5 Wins Produced
- 0.417 WP48
If Howard could hit 75% of his free throws, though, he would have scored 95 more points, produced 3.1 additional wins, and he would be currently posting a 0.486 WP48.
The examples of Shaq and Howard illustrate the importance of hitting free throws. Missing these shots reduces the number of points a team scores and that reduces the ability of a team to win.
Of course, hitting free throws – by themselves – are not enough to win games. You also have to efficiently shoot from the field, rebound, create turnovers, and avoid turnovers. So coaches do have to focus on more than free throws. But if it’s true that coaches can change free throw percentage (and I am not sure this is the case), then they are throwing away points by not spending more time on this issue.
As for Southern Utah, obviously we need to do more than just hit free throws. In fact, if we did all the things I noted above, we would be a dominant team in the Summit League. As it is, the Thunderbirds – after winning their first game in the Summit League tournament today — will need to win two more games to reach the NCAA tournament. And if that happens, SUU might start to become known for something besides an underrated academic program (really, it’s quite good), a wonderful Shakespearean festival, and the scenic beauty of Southern Utah.
– DJ
The WoW Journal Comments Policy
Our research on the NBA was summarized HERE.
The Technical Notes at wagesofwins.com provides substantially more information on the published research behind Wins Produced and Win Score
Wins Produced, Win Score, and PAWSmin are also discussed in the following posts:
Simple Models of Player Performance
What Wins Produced Says and What It Does Not Say
Introducing PAWSmin — and a Defense of Box Score Statistics
Finally, A Guide to Evaluating Models contains useful hints on how to interpret and evaluate statistical models.
Alex
March 9, 2009
There’s a nice bit in ‘Andy Roddick Beat Me with a Frying Pan’ about teaching a guy who had never played basketball to shoot free throws. It makes a convincing case that anyone willing to learn who finds a good teacher could shoot at least 75%.
Anthony Porter
March 9, 2009
What do you think about Mark Cuban burning you at the Sloan Conference, saying that you “have the dumbest data he’s ever heard of”?
axim
March 9, 2009
if shaq was a 75% free throw shooter, he probably would not have been fouled this much. If he were a 75% free throw shooter his career would have unfolded much differently
JAW
March 9, 2009
That’s a great point Axim. There’s an interaction between times at the line and free throw %
Also, Alex, there’s two problems w/ that statement:
1) I can shoot free throws pretty well at this point, after playing an NBA level game my legs would be jelly and I’d shoot terribly. That’s one issue.
2) Most people have normal-sized hands, I think that Howard and Shaq might just be among the class for whom their hands are too big to shoot well from that far away. They actually maybe should try going underhand, or something.
jbrett
March 9, 2009
If Shaq was a 75% free throw shooter, he would have made a few thousand more largely-uncontested zero- to 24-inch shots. Hard to see a bad way for that to turn out.
Alex Allain
March 10, 2009
I think something about your data is not right–either in this article, or a previous. In 2008, you wrote “In contrast, Robinson connected on 74% of his shots from the line. Has (sic) Shaq matched Robinson’s efficiency from the line, he would have produced 32.9 additional wins in his career and posted a 0.365 career WP48”.
But here, you indicate that a 75% free throw percentage would have been worth over 70 wins. I can’t see how the 1% difference would have mattered. It seems like the other article was wrong?
mrparker
March 10, 2009
On Cuban’s remarks at he Sloan conference:
That gives me hope. I have been under the false assumption that divulging too much data evens out the competition to the point that if you publicly develop a superior method you would help the competition too much. Instead it seems that people are too stubborn. Thats a good thing for someone like me. I hope Berri doesn’t respond to anything cuban says. Though if I were in his position I might point out that if Cuban’s coach had “listened” to win score in 2007 then they wouldn’t have sat one of their most productive players(Eric Dampier) for a series against a lesser opponent and lost in the first round when they were one of the best teams of all time. But thats just me.
Basketball Statistical Analysis
March 10, 2009
Who has publicly developed a superior method? Because I definitely don’t see one here. I’ll give you the benefit of a doubt, though… Maybe you were talking about Kevin Pelton’s WARP.
Robert
March 10, 2009
mrparker, you’re one of the best gimmick accounts ever. well done.
Michael
March 10, 2009
Does anyone have a link to this Cuban stuff? What exactly did he say and under what context?
mr. parker
March 11, 2009
Robert,
I think that joke went over my head.
Basketball stats…..,
Here’s what I don’t understand. Mr. Berri writes about alot of players being under or overrated. Inevitably overrated player is put in a situation where his “worth” must be proven and fails(cough Iverson cough Kobe). Inevitably underrated player gets a chance to prove his worth and succeeds(cough Billups cough Garnett).
I like WARP, but IMO it still overrates a lot of players. The Wizards would not get better swapping Caron Butler and Kevin Durant, but thats what Warp suggests.
The real value I take in wins produced is the cost of choosing one player over another or switching one player for another. wp48 seems to predict improvement in these situations before they happen. Other metrics fall short.
Its not the end all be all for me. I don’t think Magic was better than Jordan etc, etc.
Christopher
March 11, 2009
Well, the data, as you presented, actually emphasize how important FT% is. Shaq would go from 0.307 to 0.405 WP48 if he could shot the league average. That means that Shaq could increase his base productivity by 33% just by practicing foul shots. For Superman this is “only” 17% (less but Howard is better from the line). It would be interesting to see how much each player would gain/lose in WP48 relatively to shooting the league average from the stripe.
Phil
March 23, 2009
Jaw,
Slightly off-topic, but Shaq and Howard both have terrible mechanics for their shooting; very jerky movements.
There are plenty of players with large hands that are superb shooters – Yao and Dirk have comparably large hands, but are great shooters. I remember seeing a print of Sabonis’ hands in the Niketown in Portland, Oregon. They were HUGE, but he was a superb shooter.