APBRmetrics

Coinciding with October 11 being National Coming Out Day, TrueHoop has a couple of blog posts on the subject, with obvious, special focus on the circumstance of Jason Collins. And more particularly, the issue of whether or not he will be a player in the Association this year.

Henry Abbot writes the following paragraph: "If he's signed to an NBA team, Collins is not likely to make the team much better. It could be that there are straight basketball reasons he remains unemployed."

This, it seems to me, is a very strange paragraph to write. Not only because the first sentence is almost certainly untrue, but because the second sentence is one which can be checked by readily available evidence.

Now, I'm a +/- guy so my first and second reflex is to go to Jeremias' site, and what you find there is that Jason Collins last year was a very, not good player, with a rating of -3.9 (the 47th worst on the list). And for special distinction, the numbers for 2012-13 say he was the worst offensive player in the game. Then, given that at 34 he is very much on the wrong side of the aging curve, next year he should be expected to be distinctly worse still.

So, in +/- terms, next year Collins is not only likely not to make a team much better; he is likely (when on the court) to make a team much worse. So, there clearly are straight basketball reasons he remains unemployed.

But if +/- is only so much voodoo, there are other sources that confirm the point. You go to basketball-reference and query the database to find how many player seasons there have been for centers, aged 34 or above, and WS/48 <= 0.054 (what was Jason Collins' rating was last year with decline anticipated), and you get a very short list.

In this century, the only two players to meet these criteria, where this accomplishment didn't mark their last year in the NBA were Chris Dudley and Francisco Elson. And for these two, their careers lasted just one more year.

So, does the experience of Chris and Francisco offer hope to Jason Collins that he has at least has a fighting chance to get a job this year. Well, maybe. But it should also be noted in xRAPM terms, both of these players posted distinctly higher ratings in year n-1 than Jason Collins did last year.

This said, with reference to what player experience might Jason Collins expect a job offer? When I look at the list of players that meet both the aforementioned basketball reference search criteria and having an xRAPM (or fake xRAPM) worse than or equal to -3.9, the only examples I find are Bill Wennington and Joe Kleine.

So, what's the bottom line? First, there are indeed "straight basketball reasons" to believe that Jason Collins has essentially zero chance of being on a roster before the start of the season. Furthermore, based upon expected performance, only were there to be a very abnormal rash of injuries to NBA centers would we only possibly expect to see him called up mid-season.

Given this history, it will be rather unfortunate to see any unpleasant speculation about bias playing a central role in his not being offered a contract. It would not be fair, either to the issue or to Jason Collins.

Indeed, if we believe that the modern NBA is a bit better at counting than its 1990s counterpart, there is no historical precedent for a center of his last season performance (and at his age) to see a return to the NBA.

No, no center has ever been that "bad" and played in a season, but no center has every been like Jason Collins, with the possible exception of his brother.

He's actually a plus/minus star. You're looking at xRAPM, where the prior partly depends on box score stats and the final number is a mix of plus/minus and box score stats. That's Jason's failing: he doesn't rebound, score, block shots, or do much of anything that shows up in traditional box scores. But he's one of the best post defenders in modern league history and sets monster screens.

Using "pure" RAPM, he's had several seasons with +3 on defense. In 2005 he topped out at an incredible +6.3, one of the highest ever. His offense didn't normal cancel out the effects of his defense either, as he's normally been above 0. If Battier was the no-stars all-star, Jason Collins is definitely the starting center.

xRAPM improves the prediction with introducing those stats, yes. On the aggregate, it's better at guessing player value, but Jason Collins is an outlier. He's a unique player lost in the obsession with traditional stats. He's like a specialist pitcher to use versus lefties, and he's so good he's almost in the running for an award but he's used so sparingly he's lost in the shuffle. He's more of a situation player. Versus big post centers, he has tremendous value, and in these last years of his career that's when his teams have been using him.

http://insider.espn.go.com/nba/story/_/ ... s-all-star
In the 2010-11 playoffs, the fifth-seeded Atlanta Hawks beat the fourth-seeded Orlando Magic in six games in the first round of the playoffs even though the Magic had won eight more games in the regular season. This wasn't a shock-the-world upset, but how the Hawks pulled it off raised some eyebrows.

Collins was the star of the series. He averaged 17 minutes per game and had only one job on his to-do list: stop Dwight Howard. That was a tall task considering Howard was by far the most dominant big man in the league and finished second in the MVP voting that season. But stop him he did. Howard averaged 21.9 points and 13.5 rebounds per 36 minutes during the regular season, but with Collins on the floor in the playoffs, Howard's averages plummeted to 16.1 points and 12.2 rebounds.

More importantly, Collins' effort translated to winning. When Howard played 155 minutes without Collins on the court, he averaged 26.9 points and 13.5 rebounds per 36 minutes, and the Magic outscored the Hawks by 20. But the Hawks outscored the Magic by five points in the 103 minutes with Collins on the floor against the MVP candidate. Superman met his kryptonite, and the Hawks prevailed.

...

This wasn't just a one-series blip. Going back to when the data became available in 2007-08, Collins has limited Howard to just 47.1 percent shooting and 16.5 points per 36 minutes while the two have shared the court in the regular season, according to NBA.com/stats. When Howard played with Collins on the bench? Those numbers jumped to 60.1 percent shooting and 19.5 points per 36 minutes. Similarly, Collins' teams have lost by a total of 146 points (minus-11.3 points every 48 minutes) with him on the bench and Howard on the floor. With Collins on the court, Howard's teams have lost by nine points, or about three points every 48 minutes.

And actually, he's not the detriment on rebounding people think, because he boxes out well:
http://www.basketballprospectus.com/art ... cleid=2116
The Maymin-Maymin-Shen team found that Collins increased his team's defensive rebound percentage by more than any other player from 2006-07 through 2009-10 despite never grabbing more than 14.4 percent of available defensive boards (league average for a center is around 22 percent). Subjectively, the explanation for this discrepancy has been that Collins is so good at boxing out he allows his teammates to grab additional rebounds. By looking at player positioning, optical tracking might eventually allow us to quantify how much less likely players boxed out by Collins are to secure offensive rebounds.


Jason Collins hasn't been signed because there aren't any good opportunities yet. Jason Collins is really useful versus big post scorers, so he's a weapon on the bench for Howard, and maybe a couple others like Hibbert or Bynum. So he could be picked up in the west for teams fearing Houston. But look at the top teams: Grizzlies have Marc Gasol. Spurs have Duncan and a deep cast. Thunder have Perkins. Houston has ... Howard. Clippers are a possibility, since Doc is there and their frontcourt defense is atrocious. Miami could have picked him up as a counter for Indiana, but they went after Oden. He could be picked up halfway through the season after some injuries pile up and teams aim for the matchups in the postseason. It's not time to panic yet.

AcrossTheCourt, I'm not sure I see the force in your criticism of my remarks.

Whatever Jason Collins is or was he isn't or wasn't a +/- star overall. He was at one time an exceptional defensive player (and at the same time a very good player on net) but over time his precipitous offensive decline overcame this positive, such that on net at age 34 he was very, not good player. So says xRAPM (via Jeremias).

Now, it may or may not be the case that a defensive specialist like Jason Collins is especially disadvantaged by switching from a "pure" RAPM (what I suppose uses only a year x-1 value as the prior for x) to Jeremias' xRAPM (what incorporates box score stats to become part of the prior).

The relevant technical issues aside though, what is the alleged size of said disadvantage? You note in 2005 (by common account his career year) that "pure" RAPM shows a defensive rating of 6.3 but this compares to an xRAPM defensive rating of 5.9, what was fourth best in the NBA. Is this 0.4 difference either big or relevant in terms of the point I was making?

And as for:

AcrossTheCourt wrote:His offense didn't normal cancel out the effects of his defense either, as he's normally been above 0.

I have no idea what data supports this claim. (What is the source of your "pure" RAPM?) xRAPM has his rookie year being his best offensive year, and even then it was negative.

The bottom line is that were Jason Collins a "unique player lost in the obsession with traditional stats", this would show up in xRAPM, but it does not. What it shows is that he is an old player, getting older, already in the bottom decile of the NBA. As such, on the playing merits, one should expect that there is little chance for him joining a roster any time soon.

Might there be a late-season pickup by some team hoping that he could put a body on Dwight Howard (or someone other, supposed dominant offensive center) for a few minutes a game? Sure, that could happen. But it wouldn't necessarily make it rational, given the large, net negative of his expected rating and the myriad other ways that alternative late-season pickups might yield better expected results on the scoreboard.

... he could put a body on Dwight Howard ...

This particular expression should perhaps go away, given the circumstances.

Bypassing comment on Mike G's comedic stylings, a further word is actually appropriate on the question of whether there is a job available for Jason Collins in today's NBA.

Kevin Arnovitz writes tellingly: "As the league gets stretchier -- with some teams employing as few as four conventional big men -- fewer NBA jobs remain for a center whose primary on-court asset is interior defense."

Issues pertaining to defining "stretchier" aside, what is clear, at least in a +/- world, is that conventional centers aren't important offensive threats in today's game. As such, why would you want to hire someone who has huge offensive liabilities of his own to stop a player with an offensive rating of only 1+. Well...you wouldn't.