APBRmetrics

Ilardi · Joined: 15 May 2008 Posts: 265 Location: Lawrence, KS

I've just calculated mid-season adjusted plus-minus numbers for 2008-09, using the same multi-season methodology that Aaron B. and I used last year to reduce model noise (http://www.82games.com/ilardi2.htm).

Specifically, I used all seasons from 2003-2009 (Through Feb 3, 2009), but weighted prior seasons much less heavily (.125 for 07-08, .078 for 03-07 regular seasons, playoffs double).

Here are this year's Top 10 on overall APM:

Team Player Minutes Offense Defense Error Total
CLE James, LeBron 1807 11.31 5.70 1.20 17.02
NOH Paul, Chris 1571 9.51 6.78 1.57 16.29
BOS Garnett, Kevin 1464 6.49 6.93 1.35 13.42
PHI Iguodala, Andre 1858 4.14 8.99 1.27 13.13
MIA Wade, Dwayne 1826 10.70 1.85 1.32 12.55
HOU Ming, Yao 1408 3.49 8.11 1.21 11.60
POR Aldridge, LaMarcus 1770 4.65 5.56 1.39 10.21
DAL Kidd, Jason 1651 4.84 4.65 1.14 9.49
ORL Lewis, Rashard 1807 5.78 3.58 1.09 9.37
SAS Duncan, Tim 1587 4.78 4.22 1.31 9.00

(Sorry about the lack of formatting; I simply pasted straight from an Excel table - I'll be happy to fix it if someone can step me through the process on this interface.)

A quick observation: Chris Paul's defensive rating is dramatically higher than it was last year (improving from -4.54 to +6.78 this season). As a result, he now battles LeBron for the greatest overall APM impact.

I'd be curious to hear your thoughts on what (if anything) might account for this marked improvement, especially from those of you who have watched the Hornets extensively for the past couple seasons . . .

Ryan J. Parker · Joined: 23 Mar 2007 Posts: 711 Location: Raleigh, NC

Just use the Code button:

Mountain · Joined: 13 Mar 2007 Posts: 1527

What steps? I tried using on one of my excel excerpts in my most recent post (1.Post section. 2. Highlight and click Code.) and it came out all scraggly and I couldn't fix it in repeated tries to adjust it.

Ryan J. Parker · Joined: 23 Mar 2007 Posts: 711 Location: Raleigh, NC

Well I edited it with vim first. Embarassed

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supersub15 · Joined: 21 Sep 2006 Posts: 273

Ilardi · Joined: 15 May 2008 Posts: 265 Location: Lawrence, KS

Back to the question of CP3's defensive improvement . . .

Last year, Paul's opposing PGs had an eFG% of 51.8%; this year it's down to 46.7%. Likewise, this year opposing PG assists are down, turnovers up, iFG% down, and PER down. All that with Chandler missing major minutes this year (and playing much less effectively on d when he's been in).

Ryan J. Parker · Joined: 23 Mar 2007 Posts: 711 Location: Raleigh, NC

Mountain · Joined: 13 Mar 2007 Posts: 1527

It is a dramatic turnaround.

I don't have deep first-hand knowledge on the situation.

Wonder how much is related to Posey. What's his defensive adjusted in New Orleans, single year or under the new weights?

Or maybe more importantly did the departure of Pargo and Jackson (good on raw team defense on/off) help Paul rate better- without those comparisons? Did the end of the two PG guard sets make Paul perform better?

Ilardi · Joined: 15 May 2008 Posts: 265 Location: Lawrence, KS

This season:
Posey on offense: -0.16
Posey on defense: -1.43

I like the hypothesis about the end of the 2-pg sets this year giving CP a big boost on d, as it means he's no longer trying to guard 2s who are often 6+ inches taller.

bastillon · Joined: 04 Nov 2008 Posts: 55

dudeimstoked · Joined: 15 Oct 2007 Posts: 24

Mountain · Joined: 13 Mar 2007 Posts: 1527

The 2 PG thing is probably part of it but Paul probably is playing better defense too. Hungry to advance.

Posey is near enough to neutral on both offense and defense which is not bad for a 6th man.

Mike G · Posted: Thu Feb 12, 2009 10:26 am Post subject:

Sorry if it's been clarified already, but some questions still, about Adj+/- :

- Is 'garbage time' discounted at all? I know Dan R adopted a pretty strict policy about it, early on.

- It was mentioned that a possession doesn't count if it's less than 5 (?) seconds to play in a period. Otherwise it is considered to be a full possession?
Would it be better to call 12 sec .50 of a poss, 3 sec = .125 poss, etc?

- What about 'special situation' lineups: At the end of a period, you may put in 5 shooters, or 5 defenders. Especially in combination with the (few seconds) situation above, defenders may look pretty good on the average such possession. And the shooters/ballhandlers may look pretty bad.
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bchaikin · Joined: 27 Jan 2005 Posts: 690 Location: cleveland, ohio

Chris Paul's defensive rating is dramatically higher than it was last year (improving from -4.54 to +6.78 this season).... I'd be curious to hear your thoughts on what (if anything) might account for this marked improvement...

wow - so he's dramatically better on defense now than he was just a year ago because adjusted +/- says so?...

how about looking at some new orleans hornets / chris paul on court/off court numbers for last year and this year (courtesy 82games.com):

here are hornets numbers with paul on court:

-----year--------------0708-----0809
pts/100poss off----116.0----115.0
pts/100poss def---107.6----106.1
--difference--------- +8.4 ---- +8.9
--min played-------- 3004 ---- 955

i don't see a whole lot of difference here from last season to this season - the offense is a bit worse now than last year, and the defense a bit better. now let's look at the hornets with paul off the court:

-----year--------------0708-----0809
pts/100poss off----100.6----- 98.9
pts/100poss def---101.4----113.5
--difference---------- -0.8 ---- -14.6
--min played-------- 1685 ----- 570

whoa - big difference here. without chris paul on the floor the hornets are much worse on defense now than just a year ago when paul was not on the floor. they allowed 101.4 pts/100poss without paul in 07-08, but a much worse 113.5 pts/100poss without paul now...

in 07-08 with paul their def pts/100poss allowed was 107.6, but much better without paul at just 101.4 pts/100poss allowed. last year in the chris paul thread you tried to convince us that paul was such a poor defender because of this that his poor defense for all intent and purpose negated his excellent offense...

but now a year later in 08-09 they are at 106.1 pts/100poss allowed with paul, better but not by much than in 07-08 at 107.6, yet without paul the team is much worse on defense now than a year ago at 113.5 pts/poss allowed per 100 possesions...

so because of what happened when chris paul was not on the floor both seasons you are trying to say that paul's defense is dramatically better now than a year ago, when what has occured when he was actually on the floor is not dramatically different than a year ago?...

how does what happened when paul did not in fact play affect his defense dramatically?...

the hornets went 56-26 last year in 07-08 and were 11th in the league in defense (lowest pts/poss allowed) and paul led the team in minutes played...

so far in 08-09 the hornets are on pace to go about 49-33 to 50-32, and the team is 13th in the league in defense, and paul is again leading the team in minutes played...

and the hornet's pts/poss on offense (116.0/115.0) and defense (107.6/106.1) are about the same each season with paul on the floor, and paul's stats across the board this year are quite similar to last year (shooting a bit better, almost 3%, rebounding about 25% better now)...

paul was a better than average to good defender in 07-08 (actually got the most votes among PGs for the all-D team, more than either billups or kidd), primarily because of his high steals, and so far in 08-09 is a better than average to good defender, again primarily because of his high steals...

Mountain · Joined: 13 Mar 2007 Posts: 1527

Good add to the analysis Bob.

I looked at Paul at counterpart level and in player pairs for current vs. last season for differences. I also looked at the on/off but I guess I failed to compare equivalent parts season to season.

It does look to me that the off data is having a significant impact on the adjusted estimate, maybe too much. Here the very strong weight for the current season may perhaps be amplifying Paul's defensive number.

This is a challenging task.