In Defense of Being Young

By:
Published: October 22, 2014

Aside from having seemingly every player injured for significant portions of the season, there has been nothing more frustrating in the last 2 seasons than watching opponents carve up New Orleans defenses night after night.  The last two versions of New Orleans basketball have played unequivocally shameful defense.

There have been a lot of explanations thrown at the inferior defense—poor personnel, Monty’s insistence on hedging, injuries, etc.. but I think the most glaring one has been staring us in the face this entire time.  It has been considered, but perhaps not heavily enough.  The Pelicans were just young.  Really, really young.  Though system certainly impacts the results a team’s defense generates, it’s hard to run a business when the vast majority of the employees are interns.  The NBA’s learning curve is steep and it shows in records.

So how much of the terrible defense from these 2 years is explained by age?  Monty Williams has coached New Orleans for 4 years, so I took New Orleans’ defensive rankings from the last 4 years and compared to them to their “age rankings.”  The results are below.

New Orleans Age vs. Defensive Performance

Pelicans

 

 

 

 

 

 

 

It really isn’t that surprising that the Pelicans defensive performance went into a steady decline after Chris Paul and crew left New Orleans, so I decided to dig a little deeper.  I took the 5 youngest teams from the past two seasons (the ones in which New Orleans had a horrible defense) and repeated the process to see how strong the relationship was between a team’s weighted average age and its defensive performance.

Defensive Ratings of 5 Youngest Teams, 12-13 and 13-14

Team

 

 

 

 

 

 

 

There are two notable exceptions here (in yellow), the first being Houston in 12-13.  Houston had a dominant anchor on defense, Omer Asik, the Pelicans’ biggest acquisition of the summer.  The only other team to overcome its youth and register a respectable defensive rating is last year’s Magic squad, which is nothing short of a miracle (daps Jacque Vaughn).  Every other team (including the Pelicans, in green) has been terrible

Quantifying individual defensive ability

Young teams are bad at defense because they are made up of young players—and though it’s hard to quantify individual defensive ability, RAPM is becoming an increasingly popular/effective tool to evaluate NBA players at an individual level.  For what I wanted to research, I required a type of RAPM that did not use priors to guide RAPM scores (many of these priors effectively penalize young players), so I got in touch with Talking Practice, who was nice enough to give me some defensive values from the last few seasons.

I took all of the NBA players from the last 4 years and placed them into “age bins” for each season.  Each of these years was grouped into 5 age bins- Group 1, 2, 3, 4, and 5, with 1 being the youngest and 5 being the oldest.  I was looking for something very specific- what amount of players in the younger age bins registered as positive defenders?

individual

 

 

 

 

 

 

The results were pretty clear- older players graded as much better defenders than their younger counterparts.  There is a bit of survivorship bias here, as many of the older players are still in the league because they have proven that they are effective players- meaning that it isn’t surprising that older players rate as better defenders.  But this just proves the point, because the Pelicans have been giving significant playing time to young guys who aren’t necessarily going to last in the league.

I don’t know how much of the Pelicans defensive performance in the past 2 years is on Monty and how much is on the players, but evidence suggests that it’s incredibly tough to create a respectable defense with young players.  Jacque Vaughn did, so it’s not impossible, but the majority of young teams in the past two seasons have been pretty damn bad at defense.  I’m not here to pretend that I haven’t been frustrated with specific things- unnecessary doubles in the post, for instance.. or Robin Lopez hedging on pick/rolls with Greivis Vasquez expected to recover to his man (heh).  And I’ve written as much.  But this season is first in a while that Monty has had anything resembling established defensive talent.  So let’s see how the team performs with Omer Asik, Jrue Holiday, and Anthony Davis before we criticize a system that just may not have had the right parts.

 

10 Comments

Leave a Reply

Your email address will not be published.