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timvp
01-29-2013, 04:56 PM
It’s difficult to quantify the defensive efficacy of NBA players. We have plenty of tools to evaluate offensive play, however judging defense is largely an exercise in traversing subjective notions -- many of which are preconceived or otherwise antiquated.

Though far from perfect, one tool we have at our disposal is Player Pairs (http://www.spurstalk.com/forums/showthread.php?t=208734). Another tool Is Defensive PER, which the charts below detail. This too has its flaws. Those flaws include: a potentially inaccurate assumed position, cross-matches that are unaccounted for, time and score, a lack of adjustment for the surrounding talent on the court, and many other potentially modifying conditions at play.

Despite those cautionary annotations, Defensive PER has value insofar as it’s an objective and impartial valuation of the defense being played by each player.

Mins - The number of minutes the played at the position
P48 - Points allowed per 48 minutes
R48 - Rebounds allowed per 48 minutes
A48 - Assists allowed per 48 minutes
T48 - Turnover forced per 48 minutes
eFG% - Effective field goal percentage allowed (FG% with adjustment for three-pointers)
PER - PER allowed (Defensive PER)
Players are sorted by minutes played




Point Guards
Mins
P48
R48
A48
T48
eFG%
PER


Tony Parker
1472
19.2
4.6
8.4
3.3
.440
13.2


Patrick Mills
380
25.4
4.4
7.7
5.1
.475
15.6


Gary Neal
302
23.5
3.9
7.3
2.7
.481
15.8


Nando De Colo
102
26.4
4.9
10.3
3.9
.583
22.9





Shooting Guards
Mins
P48
R48
A48
T48
eFG%
PER


Manu Ginobili
671
15.5
4.6
4.0
3.5
.431
9.0


Gary Neal
652
18.8
5.7
4.8
2.0
.491
12.6


Danny Green
616
19.9
4.5
5.7
2.6
.539
15.5


Nando De Colo
480
23.6
5.0
4.7
3.0
.430
13.2





Small Forwards
Mins
P48
R48
A48
T48
eFG%
PER


Kawhi Leonard
728
20.1
7.3
2.8
3.2
.529
15.4


Danny Green
593
16.2
8.5
3.5
2.6
.428
10.9


Stephen Jackson
517
17.1
9.6
3.5
3.1
.487
12.7


Manu Ginobili
255
17.7
5.5
3.7
1.8
.457
14.1


Nando De Colo
51
16.7
5.8
1.5
0.7
.409
9.6





Power Forwards
Mins
P48
R48
A48
T48
eFG%
PER


Boris Diaw
1016
18.9
12.0
2.4
2.6
.479
14.4


Matt Bonner
446
19.6
11.2
2.0
2.6
.482
15.4


Tiago Splitter
352
21.1
10.8
2.1
1.8
.470
15.4


DeJuan Blair
263
22.2
11.9
2.3
1.9
.480
18.8


Stephen Jackson
141
19.1
13.4
3.5
3.2
.383
12.1


Kawhi Leonard
47
14.9
8.4
1.9
1.9
.412
10.1





Centers
Mins
P48
R48
A48
T48
eFG%
PER


Tim Duncan
1269
17.6
12.1
2.2
2.3
.505
15.8


Tiago Splitter
729
18.4
14.3
1.8
2.7
.498
16.2


DeJuan Blair
215
14.8
14.1
3.0
3.4
.456
14.6


Boris Diaw
47
8.7
12.1
5.2
2.6
.333
9.6



-Manu Ginobili is the most positively influential defensive player on the Spurs according to Player Pairs. Here, Ginobili also grades out as by far the best defender on the team. Coincidence? Maybe. A result of him playing minutes against overmatched bench units? Perhaps. But it’s getting difficult to ignore what Ginobili is doing on the defensive end. He was elite six weeks ago the last time I researched these stats. Six weeks later and his defensive numbers are as good and even better in some categories. Did Ginobili take Pop’s directive to play better defense this season to heart? Personally, that’s the explanation I’m leaning towards.

-Ginobili’s Hall of Fame backcourt mate Tony Parker is also having a great defensive season. He plays almost exclusively against starters at a very strong position in the NBA and he’s doing quite well. A defense eFG% of .440 is fantastic, as is the 13.2 PER. He’d never get it but if he keeps it up, Parker should be in the running for an All-Defensive Team selection this season.

-Tim Duncan’s opposing stats are about what one would surmise. He’s such an active help defender that he’s not going to shutout opposing centers. However, he does keep them off the boards well and doesn’t give up a whole lot of points.

-Kawhi Leonard, at this stage of his career, is much better defensively when he’s off the ball and is free to make plays. He’s not yet categorizable as a lockdown defender. These stats fit that narrative. While he forces the most turnovers of all the small forwards, his other numbers are underwhelming.

-One of the biggest surprises is that Defensive PER suggests that Danny Green is better at defending small forwards rather than shooting guards. Subjectively, it has appeared to be the other way around. However, we have seen Leonard switch to guard shooting guards more frequently as of late, so perhaps there is something to this.

-Tiago Splitter doesn’t jump off the page here. At center, he gives up too many rebounds, which -- honestly -- fits with subjective observations. Other than that weakness, though, his numbers compare favorable to Duncan at center. At power forward, he does a much better job limiting rebounds. And while he gives up more points there, the opposing eFG% is impressively low.

-The backup point guards are an interesting group. Nando De Colo is getting roasted … and that’s bound to happen to a tall rookie who is taking on smaller and faster players. Patrick Mills vs. Gary Neal is close to even other than one aspect: turnovers. Mills is always really active on D and that appears to be manifesting itself in the form of forced turnovers. If he keeps that up, that’s another reason why the Australian may be the best answer at backup point guard.

-At shooting guard, De Colo is a much better defender (and, wow, even better at small forward). Considering that most shooting guards are about his size, that’s not in the least bit surprising. Neal is also much better defensively at shooting guard. But, yeah, we all knew that already. Overall, the Spurs are doing a great job of defending shooting guards.

-Many of us were surprised at Stephen Jackson’s Player Pairs numbers. These numbers, too, are impressive. Jackson is putting up fantastic Defensive PER numbers at both small forward and power forward. He’s allowing a lot of rebounds but he’s also forcing a lot of turnovers and doing strong work eFG%-wise. Maybe Jackson is better than what our eyes tell us when he’s molassesing out there.

-Boris Diaw looks to be doing a better than average job. He gives up a lot of rebounds but everything else is strong. He has a small sample size at center but so far he’s no worse for wear despite his size disadvantage.

-Matt Bonner is the same ballpark as Diaw. Slightly better on the boards; slightly worse defending his man. Makes sense.

-It’s a small sample size but Leonard has been really good defensively at power forward. The fact that both Leonard and Jackson are doing well at power forward gives Pop a whole lot of flexibility going forward.

-DeJuan Blair’s stats are interesting. He’s much, much better at center. Considering how much his athleticism as declined this season, that shouldn’t be shocking. At this point, his strength in the post is at a much higher level than is his quickness on the perimeter. At center, Blair has been pretty darn good so far this season … especially considering how historically horrible he has been at Defensive PER.

-Judging solely on these statistics, here are some conclusions: Splitter probably would be best served as a full-time power forward (and, hey, that would correspond to the Aron Baynes acquisition), Mills should be the backup PG, if Neal plays it should be at SG, Blair should stick to center, De Colo should be used as a swingman and Pop should liberally utilize small ball.

Brunodf
01-29-2013, 05:09 PM
Thanks. But those stats are weird, how is Splitter better as a Center? if as a PF he is a better rebounder/defender.

timvp
01-29-2013, 05:12 PM
how is Splitter better as a Center? if as a PF he is a better rebounder/defender.Oops, meant power forward. Thanks.

TDMVPDPOY
01-29-2013, 05:19 PM
ur analysis.....how come you didnt say a word about that hero PG of urs....or do you want me to say it...

Bruno
01-29-2013, 05:19 PM
If it's from 82 games.com, aside of the issue with the cross matchups, they really got in the wrong for who is playing backup PG. When Neal is paired with De Colo, they are assuming that Neal is playing/defending PG and De Colo SG which is wrong. Neal and De Colo have been paired quite a lot (146 minutes) so it's really screwed Neal PG defensive numbers and De Colo SG defensive numbers.

Brunodf
01-29-2013, 05:20 PM
Oops, meant power forward. Thanks.

Ah that makes sense.

When the Spurs uses switches to defend the PnR and the guard misses against a PF/C, who gets the defensive stats?

TDMVPDPOY
01-29-2013, 05:35 PM
so timvp

whats the standard you would accept for a bench player and for starter? thats acceptable....

cause i look at TP....whether his a starter or playing against the bench...his defensive per, is not good

benfti
01-29-2013, 05:35 PM
timvp, are you on some conspiry with one of my companies competitors to find any way possible to make me avoid doing actual work?

Chinook
01-29-2013, 05:44 PM
How much of Splitter's increased production at the power-forward spot is simply due to playing with Duncan, and not really that he's playing the four as opposed to the five? I guess that's hard to find out unless Baynes gets into the rotation (and even then, Aron's more likely to be the power-forward in that case, anyway). I think that this chart shows that Splitter just plays best with Duncan, which also happens when he's playing with the starting unit. The same can be said of many players on the team.

TMTTRIO
01-29-2013, 05:50 PM
-Manu Ginobili (http://www.surfcanyon.com/search?f=slc&q=Ginobili&p=wtigck) is the most positively influential defensive player on the Spurs according to Player Pairs. Here, Ginobili also grades out as by far the best defender on the team. Coincidence? Maybe. A result of him playing minutes against overmatched bench units? Perhaps.
So who cares whether it's against the starters or the bench players he's doing something. Besides he's a bench player anyway.

TDMVPDPOY
01-29-2013, 05:50 PM
How much of Splitter's increased production at the power-forward spot is simply due to playing with Duncan, and not really that he's playing the four as opposed to the five? I guess that's hard to find out unless Baynes gets into the rotation (and even then, Aron's more likely to be the power-forward in that case, anyway). I think that this chart shows that Splitter just plays best with Duncan, which also happens when he's playing with the starting unit. The same can be said of many players on the team.

im telling you from watchin the games, his probably the best big on the team defensively....

tim duncan is nothing more than a tosb defending the other weakass big, while splitter is force to defend the main big thats the scoring threat to use up his 6 fouls....

Dr. Robert Lee
01-29-2013, 06:06 PM
MANU IS BEASTIN 'PER PAR. Per par. Tbh.

Dude's one of the most underrated defenders in the game of basketball today.

Meanwhile, Gary Neal just let some trash blow by him for another easy score. Fkn pathetic. And looks like he just clanked another hero off the back rim.

Mel_13
01-29-2013, 06:22 PM
-Judging solely on these statistics, here are some conclusions: Splitter probably would be best served as a full-time power forward (and, hey, that would correspond to the Aron Baynes acquisition), Mills should be the backup PG, if Neal plays it should be at SG, Blair should stick to center, De Colo should be used as a swingman and Pop should liberally utilize small ball.

Something's gotta give. If you go to a 4 big rotation with Baynes as the backup center, extend Splitter's minutes at PF to maintain his current playing time, and liberally utilize smallball; then Diaw's minutes will have to be reduced drastically. Baynes/Diaw would have to be much better than Splitter/Diaw for that to result in a net benefit for the team. Squeezing Baynes into the rotation at Diaw's expense seems unlikely to me.

As to the position we refer to as backup PG. It is an easier term than 'reserve guard who plays next to Manu while Tony rests and usually guards the opposing PG but has no real PG responsibilities on offense other than to advance the ball into the frontcourt and pass the ball to Manu'. I like Mills for that role. It reduces Neal to the role of situational shooter/instant offense which he is well suited for.

ElNono
01-29-2013, 06:44 PM
Haven't seen opposing player PER as a total measurement of defensive prowess before. Normally I've seen it mixed up with other stats like DWS, etc... props for the novelty.

Do you know how league-regarded great defenders rank with this metric? ie: does Chandler ranks high against other bigs by solely looking at this stat? That's normally a fair good indicator of accuracy.

ElNono
01-29-2013, 06:46 PM
BTW, thanks for the writeup and props also for trying to tackle this on a scientific way... it's been awfully difficult to gauge defensive impact on the NBA translated to numbers.

Mel_13
01-29-2013, 06:49 PM
Haven't seen opposing player PER as a total measurement of defensive prowess before. Normally I've seen it mixed up with other stats like DWS, etc... props for the novelty.

Do you know how league-regarded great defenders rank with this metric? ie: does Chandler ranks high against other bigs by solely looking at this stat? That's normally a fair good indicator of accuracy.

Click on the team. Then click on the player. Then click on 'by position'. Chandler's opposing centers have a PER of 16.6.

http://82games.com/

therealtruth
01-29-2013, 08:08 PM
Is Splitter the starting power forward or starting center?

ElNono
01-29-2013, 08:16 PM
Click on the team. Then click on the player. Then click on 'by position'. Chandler's opposing centers have a PER of 16.6.

http://82games.com/

I was hoping you could rank them... Oh, well... I see a lot of clicks in my future to answer my question... the 16.6 number looks already kinda suspect (as far as gauging defensive prowess)

Russ
01-29-2013, 08:53 PM
I wonder what Bowen's defensive PER efficiency was? It may not have been that great, perhaps for the same reason that Kawhi Leonard's isn't that great.

And some guy on the second unit might have a good statistical rating for similar reasons.

This is a fascinating analytical window into the Spurs' defense, but in the end, when it comes to D, I think the ultimate test is the eyeball test.

Spursfanfromafar
01-29-2013, 10:15 PM
Timvp, player pair numbers + 82games's Defensive PER are a good combination, but not sufficient, in my opinion. There is also the Synergy on court/off court stats that establish the defensive value of lineups + players. i think without including that in to the picture the defensive reading will not be complete. Firstly, because defensive PER is a box score stat and player pair does not take into account other dimensions (other players' role in the pair's efficiency).

quentin_compson
01-30-2013, 02:14 PM
It would be interesting what the league average of defensive PER is. It might be something around 15, as I remember having read that this is about the average number of offensive PER in the NBA.