In 2014, DRPM ranked Lebron 23rd among SFs, well behind Jae Crowder (#12). Paul Pierce was ranked #2, just ahead of Tony Allen.
In 2015, DRPM ranks Lebron #7. Tony Allen moved up slightly to #2, but Paul Pierce dropped all the way to #22 and Crowder dropped all the way to #48.
If DRPM is really measuring the individuals and not team effects, why is it moving the players who changed teams all over the place?
To assume that a change in defensive RPM the year after a team change, must be a result of the said team change, is flawed logic. There are more things at play than just a change in team.
For example, a person's role can change - e.g. Avery Bradley. One year your only responsibility is to go out there and play hard D for 10 minutes a night. The next year the team tells you you need to play 28 MPG, and they want you to be the #3 offensive option. Now you can't play defense at 150% on every possession, you need to pace yourself and make that energy last.
A player's mental circumstances can change - e.g. Zach Randolph. Known early in his career as a lazy guy with a weight problem and a horrible work ethic. He's completely turned that mentality around (well, expect for the weight) a long time ago, and when he did his play improved dramatically as a result.
A guys physical circumstances can change - e.g. Kevin Garnett. Garnett was one of the NBA's greatest offensive players in 2008 when he came to Boston. Now he can barely contribute on that end of the floor. Much of that is a result of age - he's just not as explosive athletically as he once was, and he can't do the things he once could. Defensively his numbers are still good (+2.32 DRPM, 11th among PF's) but that's a far cry from where it would have been when he was 30 years old.
Players develop. Andrew Wiggins had a horrible DRPM last year of -2.13 was horrible last year, ranked 70/80 among NBA SF's. But he's a rookie. As he learns the game, learns rotations, learns how to read players, I'm sure that his defense is going improve dramatically in the coming years.
Motivation - a guy who has just won a championship might suddenly see his hunger for victory fade a little. His Defense (and hence DRPM) may suffer as a result.
There are many, many factors that could have changed. For example, Paul Pierce didn't only change from one team to another - he also got a year older. Maybe he just lost a step defensively? I mean the guy is in his mid-to-late 30's so that's kind of expected.
Lebron changed teams, and his rating improved. Maybe that's just because he got knocked out of the playoffs the prior year, and so he came into the new year especially driven and motivated because he didn't want to get knocked out again. How can we conclusively say that the rating changed because he changed teams?
Joe Crowder saw a much alrger role with far greater minutes in Boston, where he played around 25 MPG as a constant rotation player (versus about 10 MPG as a end of bench guy in Dallas). maybe he had to pace himself in that bigger role, and hence his defense dropped off.
There are a number of factors that can explain these changes in RPM beyond simply "the player changed teams". Some of the changes may be due to team environmental circumstances, sure. But that's true for any statistic. You can name almost any stat you like, and I can make a case as to how that stat could vary for a player based on team environment changes.
Likewise, for every player who DID have their DRPM change after they changed teams...I can name you a player who had their DRPM change despite staying on the exact same team.
Avery Bradley is one example. He ranked 6th among PG's with a DRPM of +1.22 in in 2013/14 (yes, they list him as a PG - no idea why) but in 2014/15 he dropped to +0.73 and a rank of 13th among PG's.
John Wall had a DRPM of -0.44 in 2013/14 (25th among PG) and that improved to +1.73 (4th among PG) in 2014/15. That's an improvement of +2.17 and 21 ranks.
Brandon Jennings ha a DRPM of -4.37 in 2013/14 which ranked him 68th among PG, then in 2014/15 that improved to -1.41 and a rank of 46th.
Stephen Curry improved from -0.38 and 23rd in 2013/14, to +1.91 and 2nd in 2014/15.
All of those guy stayed on the same team.
The very simply factor here is what Real Plus Minus actually represents. It represents (more or less) how much your team improves / declines when you step out there on the court. If you step on the court and your team gets worse, then having you on the court brings a negative impact. If bringing you in causes your team defense to improve, then you are having a positive impact.
Even late bench role players tend to play more than 1,000 minutes on the court over the course of an NBA season. The sample size is large, and rotations vary enough to take away much of their impact - especially on teams like Boston, which had it's roster and rotations constantly changing.
At least that's how I see it.
Topic: isaiah thomas-how to make him even better (Read 8567 times)