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Tuesday, September 16, 2014

2/29 Two Quick Links

NYSUN: Vandeweghe Would Succeed Only if Isiah Isn’t Around

[Vandeweghe's] record does come with some warts. He served as general manager of the Nuggets from 2001 through 2006, helping to rebuild Denver from a lottery team into a playoff contender. The key deal was, not surprisingly, a trade with the Knicks — he got Marcus Camby and the rights to big man Nene from New York in return for Antonio McDyess. He also made a solid move when he signed point guard Andre Miller to a free-agent deal.
However, the rest of his résumé looks spottier. He gave up three first-round picks in the sign-and-trade deal with New Jersey for Kenyon Martin, and Martin’s seven-year, $91 million contract has been one of the league’s worst values. He also passed on Amare Stoudemire in the 2002 draft … twice. One of them was the Nene choice, and the other was all-time bust Nikoloz Tskitishvili.
That said, if he’s hired by the Knicks his biggest move will be choosing the next coach … or rather, that’s what it should be. If he’s stuck with Isiah, he probably won’t accomplish much.
Nonetheless, it would offer a very slight glimmer of hope that perhaps things might get less awful. He’d presumably have the power to start trading the many misshapen pieces of this roster. And one hopes, at least, he’d have Dolan’s commitment to a genuine rebuilding project as opposed to the slapdash quick fix Isiah tried when he took over.
But it’s puzzling that Dolan can’t realize the huge public relations boost he’d get from cutting the cord with Isiah entirely. The fan base would be rejuvenated, to the point that they’d actually be willing to sit tight and support the team through the inevitable multi-year rebuilding job.

Diminishing Returns and the Value of Offensive and Defensive Rebounds
More Diminishing Returns

In some ways I think this study provides stronger evidence for the impact of diminishing returns on defensive rebounding than my previous post. The charts allow one to easily see the effects of diminishing returns, and by looking at the rebounding of all the players in each lineup, the issues brought up by coaches potentially pairing good rebounders with poor rebounders are largely eliminated.

The specific marginal values found of 0.8 for offensive rebounds and 0.3 for defensive rebounds are also interesting. These match closely with how John Hollinger’s PER weights offensive rebounds relative to defensive rebounds (ORB are weighted by the league DRB%, which is around 0.7, and DRB are weighted by the league ORB%, which is around 0.3). And again, these values suggest that Dave Berri’s Wins Produced greatly overvalues players with high defensive rebounding percentages and undervalues players with low defensive rebounding percentages because the system assumes that each player DRB contributes a full DRB on the team level. Alternative Win Score (or AWS), the variation on Wins Produced suggested by Dan Rosenbaum in his paper, “The Pot Calling the Kettle Black”, weights ORB at 0.7 and DRB at 0.3. While these values are based on an assumption and not backed by evidence (just like Berri’s assumption that both should be weighted at 1 is not backed by any evidence), the evidence from the study I have done here (and Cherokee_ACB’s study) suggests that AWS (and PER) may be a lot closer to the mark on rebounding than Wins Produced.

8 comments on “2/29 Two Quick Links

  1. Nick

    My question is why would NJ go through the trouble of having Kiki as an assistant after their prior assisant went to GM Philly and then let him go and to their biggest “rival” of all teams?

  2. Caleb

    Kiki is a terrible GM, if you ask me… just based on the examples above. Martin and Tskitishvilli? Whew. I also note that he took Carmelo Anthony ahead of Bosh, Wade and Josh Howard… all much better, in my book. Vandeweghe looks like a guy who values big names over anything else. Exactly like a certain GM who shall go nameless…

    The rebounding article mischaracterizes a couple of things about Berri, I think… for example, calling it his “assumption” that a rebound should be weighted as “1″ in his scheme. Berri’s method is based on straight math — the correlation between certain stats and wins. (Unlike Hollinger, who for better or worse assigned semi-arbitrary values to these stats). It’s hard to argue against Berri’s numbers where they relate to TEAM stats. They’re self-referential, just a statement of fact that the correlation exists.

    The problem arises in assuming the correlation can be translated to individual statistics. In practice, the biggest problem is giving credit for rebounds that would be more fairly credited to defense (in the case of defenseive rebounds) or crappy shooting/shot creation (in the case of offensive rebounds).

    Here’s another way to explain:
    Berri assigns full credit to the individual player, for a rebound that he grabs. It’s partly unfair, because the rebound was only available because the other team missed the shot. Zach Randolph grabbed the board, but maybe Balkman deserves some credit for it, because he forced Paul Pierce into a bad shot.

    Berri attempts to correct for this, by including some credit linked to team defense (Michael Finley gets as much credit for Spurs defense as Tim Duncan, but hey — it’s something)… and with a position adjustment, a mathematical trick which tries to account for the reality that big guys get most of the rebounds…

    …but it still seems that his rebound weight is off.

  3. Caleb

    weird news about Lue – why would he sign here when he can be a backup on a contending team? Sounds totally imginary.

    He’s an expiring contract, too — hard to see the point of this move, unless it’s to see what the team looks like with an actual, albeit mediocre, PG. It’s not like Jones or Morris are in our long-term plans, either.

  4. Frank

    I think Kiki is a fine GM — he actually has a plan when putting together a team unlike IT. Denver was nowhere when he came and now they are somewhere. Can’t blame him even a little bit for picking Carmelo — he is a great player and had the least risk and comparable upside at that time to the other players you listed. And missing on Skita – well, even Joe Dumars drafted Darko and no one calls him a bad GM just based on that (although he really could’ve should’ve had Carmelo at least out of that #2 pick if not Bosh or Wade. DET would be seriously scary with one of those guys).

    Re: Kenyon Martin – he was a great energy guy and player for the Nets during the championship run and has had a run of injuries that could happen to anyone.

    Look, at least Kiki has a brain in his head which is more than I can say for anyone in the Knicks front office. I’d rather have Colangelo but Kiki would be a fine upgrade from IT.

  5. Eli W

    When I talked about Wins Produced assuming that rebounds have a value of 1, I was referring to the translation from the player to team level. The value WP assigns to each team rebound is based on a regression measuring how much team stats contribute to wins, but then Berri assumes that the translation from player to team stats is 1-to-1. But it appears that is far from the case for defensive rebounds, where each player DRB contributes a lot less than one DRB to the team total because a large percentage of player DRB would have been rebounded by a teammate anyway.

  6. Mulligan

    I was about to make the same argument re: Kiki and Dumars. If Martin’s knees hadn’t completely degenerated, he would be valuable to that team.
    Also, he’s learning from Thorn right now and that dude is a master.

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