Consistent play is a concept that is incessantly talked about by broadcasters and pundits in the world of sports. How often do we hear an announcer talk about how a certain player needs to be more consistent for their team to win a game?
Other than “heart”, consistency is the most talked about aspect of basketball that no one has yet to measure. That being said, it’s actually fairly easy to come up with a basic way to look at consistency.
The following metric attempts to measure consistent effectiveness and ineffectiveness in players using John Hollinger’s game score and PER.
Like any stat, it’s not the end all, be all of all numbers, nor is it intended to be. However, it gives fans a gist of which players are consistently reliable (or unreliable). This can prove to be a valuable tool in terms of player evaluation.
John Hollinger’s game score is essentially the PER of a player’s single game performance. It has its critics, but it’s one of few statistics that measures a player’s single game performance.
By taking the standard deviation of a given player’s game scores for the entire season, one gets a number that tells us how much variation there was in the game scores. The more consistent a player was, the closer to zero the standard deviation of his game scores become.
However, simply doing this to measure a player’s consistent effectiveness is flawed. For instance, let’s take Kobe Bryant and Robert Sacre. Bryant’s standard deviation of game scores was 7.83 in 2012-13. Sacre’s was 1.83. Sacre’s standard deviation is closer to zero, so this means that his game score values had less variation than Kobe’s. This may be true, but it does not tell us which player was consistently effective.
So how do we separate the consistently effective players from the consistently ineffective ones?
We simply divide the standard deviation by the season PER. This gives us (in mathematical diction) the coefficient of variation. It tells us how consistent a player is RELATIVE to his own average.
After doing this operation, it becomes clear and obvious that Bryant is far more consistently effective than Sacre. Bryant’s coefficient of variation is 0.34, while Sacre’s is 0.54.
Here are the consistency ratings for the Los Angeles Lakers from this past season.
2012-13 CONSISTENCY RATINGS (LA LAKERS):
- Once again, the higher the coefficient of variation is, the more variable a player will perform relative to his average.
- Jordan Hill is the most consistently effective player on the Lakers. He has the lowest coefficient of variation. Again, this does not mean he is the most EFFECTIVE player on the team. It only means that one can expect Hill to play at a level near his 18.5 PER on a consistent basis.
- Steve Blake, Jodie Meeks, and Metta World Peace are great examples of players who would put in an amazing performance one night, then follow it up with a horrible game. We never knew what to expect from these guys. All of their coefficients of variation exceed 0.44.
- Another interesting observation is Dwight Howard’s coefficient of variation. He was fourth on the team this year with a 0.377 coefficient of variation. That’s great, but it’s a huge rise from his final year with Orlando, when his coefficient of variation was 0.322.
- To add more perspective to all of this, though, LeBron James’ coefficient of variation this season was a miniscule 0.19. Kevin Durant’s was even better at 0.18. Both of these guys weren’t consistently effective – they were consistently dominant.
- The fact that the Lakers didn’t have a single player below 0.30 shows that the team was plagued with inconsistencies this season, which was obvious for anyone who watched the team this year. However, now it’s quantifiable.
- This metric works well for lesser quality players who don’t see much floor time, too. Because the denominator (PER) is small for these types of players, the coefficient of variation often turns out to be large for guys like Sacre and Devin Ebanks. This tells us that they’re consistently ineffective when they play. If they DID play well, their denominator would be larger causing their coefficient of correlation to decrease.
Taking the standard deviation of game scores for guys like Earl Clark who sat in the back of the bench and rarely played early on but then became a regular can be a bit convoluted. Clark rarely played early in the season and as a result, received low game scores. In the second half he played well and became an integral component for the Lakers. As a result, up went his game scores. The variety of numbers can inflate his standard deviation and make him look like an inconsistent player when really he just wasn’t playing much in the beginning of the season. It may be more effective to only include games where a player plays at least 12 minutes. But then we ignore performances from guys who played less than a quarter and made an impact on the game. Although rare, it’s unfair to ignore this. Therefore, we include the garbage time games for Clark early in the season and penalize him for not being a regular. Again, no stat is perfect, especially in this analytics era.
This metric helps us break down players into four different groups:
- High PER, High Standard Deviation: This is Dwight Howard and Kobe Bryant. They have high PERs, but can be inconsistent at times.
- High PER, Low Standard Deviation: This is Kevin Durant and LeBron James. This is where everyone wants to be. These are guys who are consistently dominant.
- Low PER, High Standard Deviation: This is Jodie Meeks and Metta World Peace. They can put up big games, but more often than not they’re going to be average or below average.
- Low PER, Low Standard Deviation: This is Robert Sacre and Devin Ebanks. They are consistently ineffective.
The following table illustrates this notion:
This season, the Lakers had a lot of guys who had a PER below 15 (which is the league average) and a game score standard deviation greater than five. They were an inconsistent ball club.
Now while Durant, LeBron, and Kobe all had game score standard deviations greater than five, they made up for it because of their efficiency on the court. In other words, a standard deviation of five or six is not bad for super stars like LeBron or Kobe. Unfortunately for Kobe and Howard, their game score standard deviations hovered over seven. They would like theirs to be below six.
It’s all relative. That’s why it’s important to look at the coefficient of variation at the end of the day to see who consistently plays up to their own level and as previously mentioned, the Lakers didn’t have a single guy who had a coefficient of variation below 0.30.
Pretty cool! I’d love to see this turns out if you include all NBA players (and additional splits like whether they started the game or not, minutes played, home/road, etc). You could dive into things like consistent off-the-bench performers (good PER low std-dev ); the X-factors (good PER with highest std-dev), the effect of home court on consistency, and what stars in the league you can depend on night in night out.
Not a fan of PER, but interesting approach nonetheless. Wondering if you could do this with various lineups to see which lineups were most consistent and effective too.
All-time greats don’t go 1/4 In the Finals and have their overall level of play go down on the biggest stages…just sayin
Off topic, but LeBron is putting up numbers that would make 6-24 look like a very very decent shooting stat. Well, not really, but he’s now seeing what it’s like to be the man, really, against a good defensive team.
That was an Old Fashioned Arse Whooping!!!
Danny Green and Gary Neal are both guys the Spurs picked up from the free talent pool.
Warren Wee Lim says
Just as I predicted the Spurs blasting the Heat and blowing them out of the water… With DG and GN? Wow.
Didnt predict that at all. No one could have.
This is just part of the reason why a deep quality team built on good payroll management can help big time.
Duncan is playing for 12M and Parker is playing for 10. Also, getting guys like Neal and Green has nothing to do with payroll. Green came off the waiver wire and Neal was signed after playing overseas. That is just talent identification and deployment.
The Lakers are a different beast. It’s a family run business, but it’s a business that was used to run by a businessman who was more in a ‘win at any cost’ mentality than a ‘win at reasonable cost’ mentality.
While we have been wildly successful with the former mentality, we may have to shift into the second, which will require a lot of restructuring and reorganizing from the top down. Not sure if we’ll be up to it though.
“Spurs: They need to be beaten. I admire the way they play and the way they are coached about as much as I admired the way Larry Bird played and KC Jones coached. In other words – I despise them.”
Robert, if there’s any hope of Lebron, the last thing that ought to occur is another Heat title, i.e., while the chance might still be slim with the Heat not winning the title this year and next, if they instead go on to win this year and next, no way Lebron walks away from a continuing title string and so slim chance becomes zero, zip, nada, zilch. You know what they say, sometimes you’ve just got to take one for the team.
Next, for rr, if he’s here, Duncan and Parker playing for what they are means, well, next year they’ll be at just under 23 mil combined, while Kobe will be at 30, so is them 2 versus Kobe plus they get to pick up another guy for 7 mil, or 2 Danny Greens, each at 3.5 mil (which is his salary for this season). Glad for ownership that he puts rear ends in the seat, since Kobe cannot possibly be worth 30 mil in purely on the court performance.
Warren Wee Lim says
Not much on Kobe but the value of a good contract will make the team better. Duncan and Parker at combined 24 million when Gasol earns 19 by himself, I’d take the former.
Rr, if you are against this advocacy of having good contracts on the team that is able to acquire talent year after year, I cant really agree with you.
That’s fine, but you didn’t address the point. The Lakers theoretically could have signed Danny Green and Gary Neal, too. You can always add guys for the minimum, no matter how high your payroll is. And, the Lakers actually did have three somewhat analogous players on their roster: Ebanks, a young swing man they drafted and paid about 1M last year; Morris, a cheap backup PG, and Meeks, a cheap somewhat undersized spot-up shooter.
The difference there isn’t “payroll management”; it’s scouting and talent management.
As far as Duncan and Parker playing for less than half of what Kobe and Pau play for:
1. I have said many, many times that Kobe’s and Pau’s deals were a year too long and/or too expensive. I said that when they signed them. That said, I don’t really object to the deals, given what Kobe and Pau have done for the franchise.
2. I don’t know if I would call Duncan and Parker’s deals “payroll management” as much as I would call them a “tribute to Gregg Popovich’s great leadership.” Duncan and Parker want to be there. Also, those deals were signed after the new CBA kicked in. Duncan was up around 20M before that, and Kobe and Pau, if they are here or elsewhere, will obviously be playing for much less in the future.
I have a response to Warren and Slappy stuck in mod, but Slappy is right about James. The only way he leaves Miami is with a Finals loss or two, which might conceivably lead to some kind of falling out with Wade.
But if he does decide to leave Miami, I see no reason to think that the Lakers would have a better shot at him than Cleveland, Dallas, Chicago, or some other team would.
As much as I would like the idea of a LeBron-Howard led Lakers, I shudder at the psychological damage they would inflict upon themselves and the kind of media circus they’d bring with them. I would guess that they would make the Shaq-Kobe media feud tame in comparison, simply because they’ll probably be both so wishy-washy and not own up to anything that may damage their reputation.
But yeah, I would still like to have both on my team since there is no chance of getting Hibbert and Durant or something.
“That is just talent identification and deployment.”
To some extent, yes. But if you read most of the articles on Danny Green and the Spurs, the general picture that emerges is that it was talent development. The Spurs cut Green twice. His talent didn’t change. It was the grooming done by Pop, the conference call with Roy Williams, getting Green into the proper mindset – and yes, being lucky with timing to the point where Green was desperate enough to change his work habits – that made the difference. It also depends on what you mean by “talent” – Green always had the raw tools – but he needed the development the Spurs’ coaching staff provided.
This is not in any way supposed to be a backhanded dig at our coach. Just an admiration of a coaching staff – not just limited to Pop, but including Engelland, who re-worked Parker’s form and tapped into Leonard’s potential as a corner specialist in 1 summer – that puts their players in a better position to succeed than any other organization.
Renato Afonso says
I have this running discussion about PER with a lot of people. Being a former basketball player, a part-time coach (in my country’s 3rd league), a basketball fan and a mechanical engineer, I believe I know a thing or two about basketball stats. So hear/read me out, please…
PER is an amazing stat that took a long time to perfect/upgrade and that has its value. The fact that every season we set the average at 15 lets us know who was stat dominant in each particular season. Take a look at Lebron’s PER. He is the most dominant player and the numbers reflect that. Same goes for Kobe’s standard deviation, which tells us what we already know: Kobe has extremely good nights and some off nights as well. It won’t work so well on low usage players though. Yes, Jordan Hill is extremely efficient, but would those efficiency numbers hold if he played 35mpg? And even if he played those 35mpg, would he be more helpful to the team than a Pau Gasol?
PER has a lot of shortcomings, as Dr. Hollinger admits, but people tend to overvalue that stat. PER is great to discuss who’s the best player in each season. One could even use PER with W/S ratio per 48 combined to determine who’s MVP. It’s a stat that exists to make us discuss player X vs player Y. What we need to realize is real scouting stats… What’s the % of made shots by Steph Curry when he drives left? What happens when you iso Tiago Splitter in the post? How effective is the Spurs game if the game is forced to run through Splitter’s hands against a good low post defender? Those are the kind of stats teams actually use in order to come up with a gameplan… And even then, we’re still talking about offensive stats!
I really don’t care about Ron Artest’s PER standard deviation. Yes, I like it better when he scores points but I prefer to see his work on the defensive side. Think about it for a second… With Ron Artest locked in on him, would you rather see Durant slap 40p6r4a with 50-90-40 splits or see him get 18p16r11a with 35-90-30 splits? If he’s shooting less and being forced to pass the ball, it really depends on how you’re forcing him to do just that. Is it due to help defense? Is Ron Artest locking him down? Are the guys receiving Durant’s pass wide open to shoot? Are they reliable shooters? PER can’t measure Ron Artest’s defense nor can it reflect defensive adjustments made by a team throughout a game. The other thing that it doesn’t take into account is the PER of said player when he’s on court with good three point shooters or amazing pick and roll players. I mean, is Dwight’s PER really all that is about him? How many times is he double teamed when there aren’t enough shooters on the floor? How many opposing shots he didn’t blocked but altered the shooters form enough to cause a miss which he didn’t rebound?
Basically it’s an isolated stat that tells us who are the major stars. Now, I have another question about PER… How did he come up with that formula? Those weight ratios, weren’t they made to prove that Jordan had the best season ever? I love basketball stats and use them thoroughly whenever I can but this one I just don’t…
Shaq: The Big Motivator? Or Just Him Continuing His Pattern Of Taking Shots At Dwight?
Appreciate the effort in `measuring consistency´, but it simply comes down to too many numbers for me. That is, all of the stats are fine, but it´s what happens on the court game in and game out that matters-
How can anyone tap into a player´s head each night and predict with any certainty what his production will be for the game? These professionals are simply human, as Chick used to say now and again.
None of us on this planet are robots (at least not yet).
Even luck has a factor in each team´s outcome.
a shout-out to Snoopy2006,
`Talent Development´, well said man
Slappy: I understand the LeBron logic, but I think you said it all: “If there is any hope”. I know for a fact, I am going to be ill if SA wins. And we are going to have to listen to how Pop is one of the best ever, Duncan is better than Kobe, and the Spurs have done it all from a small market. And worse yet the LeBronze worship will continue win or lose. He is the modern Wilt Chamberlain (Wilt only won 2 titles, but the individual accolades put him in the best ever convo).
Now for my own pipedream (we would need Celtic permission for this):
Manny P: To once again show you how open-minded I can be, I am hereby amending my list. Doc Rivers can now be added along with Phil, Shaw, and B Scott. We have had previous luck with former Lakers, former Celtics, and coaches who have rings. If you can get 2 of those in one guy, he goes on the list. So now there are 4 ideas. Hire good people and get out of the way – this is a business !
that puts their players in a better position to succeed than any other organization.
Sure, That is what I meant by deployment–how guys are used.
Renato, good to see some posts from you, you post rarely these days. Excellent post! You addressed my thoughts on PER far more succinctly than I could.
NBA coaches, scouts and trainers are all seeking the magic formula that will give them the tool to pick the next Kobe Bryant instead of the next Adam Morrison.
Craig W. says
You simply had to see Wilt play to understand just how dominant he was at his position – against everyone. It is one of the reasons I think counting rings doesn’t really measure players any more than counting statistics alone. If this were tennis then I could agree with you, but nobody – not Wilt, not MJ, not Lebron – can win any rings by themselves. It always takes a team – and that means players and coaches.
Nice article but i dont need a 1000 statistics and numbers to know how inconsistent this team was all season long and who were the most and less inconsistent, i have eyes.
Darius Soriano says
Thanks for that insight, Fern. We all have eyes. What Andre was trying to figure out goes beyond what we see with our eyes. I mean, I think I’m a pretty astute observer and I thought this information was quite useful.
As for PER, Hollinger explained in length how he came up with the formula. It was actually quite thoughtful and reasonable, with each stat weighed to be roughly equal to 1 point.
(Points x 1.0) + (FGM x 0.4) + (FGA x -0.7) + ((FTA-FTM) x -0.4) + (OREB x 0.7) + (DREB x 0.3) + (STL x 1.0) + (AST x 0.7) + (BLK x 0.7) + (PF x -0.4) + (TO x -1.0)
Renato Afonso says
Thanks Chearn, nice to see you’re still around as well!