Why the Pistons are Misbehaving and a Quick Comment on Corey Brewer and Kobe Bryant

Posted on March 1, 2011 by

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This is the question my latest for The Huffington Post addresses.  Short answer… the attitude and abilities of the Pistons are not in alignment.  And this disconnect has led to anger and frustration (which is being directed at the coach).

In addition to a link to my work for The Huffington Post, let me direct everyone’s attention to the following stories:

A Few More Links

Quick Comment on the Value of Corey Brewer and Kobe Bryant

Henry’s story argues that Corey Brewer may be capable of making a positive contribution to a team’s success.  The post sites statistics like adjusted plus-minus.  Brewer posted a 1 year adjusted plus-minus (APM) of 0.85 with the Minnesota Timberwolves this year.  And his defensive measure was in the negative range (which is “good”).  Then again, by the same measure Kobe Bryant has a measure of -11.15 (which has to be one of the lowest APM marks in the NBA this season).  And Kobe’s defensive measure is very far in the positive range (which is “bad”). 

So is Brewer “better” than Kobe this year?  Well, APM is very inconsistent from season—to-season.   So like the weather in the Midwest (and this is something often said in places like Nebraska), if you don’t like a person’s APM just give it some time and it will probably change. 

Of course, that is a problem for decision-makers.  How are they supposed to know if a result seen from APM reflects a player’s ability or is simply the “noise” in the model?  If you can’t answer this question (and I don’t think you can), I don’t think you can use this information in making decisions.

Just for the record… according to the automated Wins Produced website (from Dre Alvarez), Brewer has a WP48 of -0.022 and an Adjusted P48 of 0.120.  Kobe’s marks are 0.207 and 0.344.  Such marks are quite consistent with what we have seen from Kobe and Brewer across each player’s respective careers (ADJ P48 has a 0.85 correlation from season-to-season; so it is quite consistent).  In other words, the box score says Kobe is much better than Brewer.  And this has always been true.

Now maybe Brewer’s defense is just amazing.  And maybe his defensive ability puts him on par with Kobe this season.  But I suspect that isn’t true.  So maybe the Knicks were wise to let Brewer find employment elsewhere.

By the way…. a statistical measure doesn’t have to be consistent with conventional wisdom.  In fact, whether a measure is consistent with conventional wisdom or not is not relevant to whether the measure is “good” (at least, that has always been my argument).  The problem with APM is not that it is defies conventional wisdom (like Wins Produced, this is often the case). The problem is that it is quite inconsistent over time.   In addition, the results are simply hard to explain (i.e. can Brewer be such a great defender that he simply overcomes all of his remaining shortcomings?).  Such problems suggest that APM probably doesn’t help people make better decisions.

– DJ

P.S. One last note… Henry doesn’t think the Knicks should have used the APM results to decide whether to keep Brewer.  He thinks they should use it to go look at more film. But if APM tells you a player is “good”, and you then go look at film, what are the odds you will walk out of the film session thinking the player is “good”?