APBRmetrics

permaximum wrote:@xkonk

Iverson's +/- playoff numbers suffer hugely because especially in Philly he played almost 95% of available minutes in playoffs. He usually came out for a min or two in a game and that small sample size taken from a game skews +/- numbers. The only playoff game 76ers played without him in a series that they eventually won, was a lose. But that doesn't mean anything at all like his playoff +/- numbers.

xkonk wrote:

permaximum wrote:@xkonk

Iverson's +/- playoff numbers suffer hugely because especially in Philly he played almost 95% of available minutes in playoffs. He usually came out for a min or two in a game and that small sample size taken from a game skews +/- numbers. The only playoff game 76ers played without him in a series that they eventually won, was a lose. But that doesn't mean anything at all like his playoff +/- numbers.

That's a valid point. Although it hasn't really hurt LeBron, who never played fewer than 86% of his team's available playoff minutes until last year, or Durant, who's been right around 90% every year except for his first trip to the playoffs.

We can also argue all day about who had worse back-ups and teammates, but it makes you wonder why the 76ers were so unsuccessful when they had the second-best player of all time playing 95% of their minutes. People complained about LeBron's supporting cast every year he was in Cleveland, but they never won fewer than 35 games while he was there, and once they made the playoffs they never lost in the first round. The few apologists LeBron had after the Decision said that he had to leave because his teammates would never be good enough to get a title, but he still got them to back-to-back 60 win seasons. Iverson's 76ers were never that successful; even when they made it to the Finals they only won 56 games.

... there's a lack of ability in today's players to take over in a playoff game where it matters. .. Yes, I rank prime Iverson second behind prime Jordan.

Between the years of 1999 and 2005 (Philly playoff years), Iverson played 62 playoff games and scored 40+ in 10 games (9-1 record...
What I'm trying to say is this is what "greatness" is about. Winning the games that matter without getting much help.

Iverson in his prime is better than LeBron, especially in playoffs...

Rd  G   2fg%   3fg%  3fgRt  eFG%    FT%    TS%       Min    TSA    Pts   Reb   Ast   Stl   TO
1  28   .444   .358   .22   .465   .753   .518      44.7   29.5   30.6   3.6   6.3   2.4   3.4
2  23   .407   .315   .18   .419   .784   .478      46.0   30.9   29.6   4.3   6.2   2.1   3.2
3   6   .347   .333   .19   .376   .782   .435      45.7   35.0   30.5   4.8   6.8   2.2   3.2
4   5   .447   .282   .24   .441   .729   .486      47.4   36.6   35.6   5.6   3.8   1.8   2.4

permaximum wrote:Found those articles about comparing different metrics on explaining the past and predicting the future. VORP(ASPM) looks like the clear winner. Most importantly it's methodology and reasoning suit my view on the matter perfectly. No surprise it's the only metric Iverson lead the league in 2001 where he had 93 first-place MVP votes out of a possible 124.

Over the four available, common years, I calculate an average difference of PPG error of 0.1, in ASPM's favor over "new" RAPM.

And then what also ought to be recognized, as I understand the presentation, is that this is a summation of the contributions of five players on the court, so on a per player basis there is no difference. If this interpretation is correct, it follows that this comparison offers no comment on the relative value of the competing metrics on the accuracy of the ratings of individual players. And for this, we need to dig a bit deeper.

On the one hand, Daniel's ASPM (and Daniel, please feel free to advise) offers a pared down regression ("Over the years, I have composed the regression a number of ways, and have gradually simplified the structure, minimizing terms to minimize over-fitting issues." http://godismyjudgeok.com/DStats/aspm-and-vorp/) what yields positive returns for both MPG and USG%. Fair enough. But note that there are theoretical reasons to believe that this such returns are not, in fact, positive on the extreme high end, and, sure enough, who is the extreme outlier in these categories? None other than AI. (From 1981 onward, he ranking 1st and 4th in these career statistics, for players playing more than 24 mpg in the latter case.)

Conversely, "new" RAPM, though it has a prior (the specifics of which I cannot recall - what might similarly exalt AI or not, on MPG and USG% grounds) also asks the contemporaneous +/- contributions to speak, and these offer a very different result, in terms of his rank. Again, as noted, his yearly best on J.E.'s site was 18th - what doesn't quite square, I think, with a 19th rank in notional HOF value.

So, my point is this: If one wishes to believe that AI is all that, and I'm just talkin' practice, so be it. But I don't think one should go to this specific rendition of ASPM to offer definitive opinion on a very outlying player.

First, apologies. I was about to amend my remarks about USG% being the concerning factor in the AI rating, when it is, in fact, only the MPG margin - where, again, he ranks #1, post 1981. To contextualize the regression results (please check) they suggest that were AI to have played every minute of every game (assume 48.4) then he could have missed every shot and free throw (TS% = 0) and improved his rating by +0.4 points per possession. The point being: AI is an extreme outlier in this dimension (and in USG%) and his relative rank is accordingly sensitive to the specification of the regression.

Second, there is perhaps an interesting conversation to be had contrasting the fact that ASPM and "new" RAPM between 2008 and 2011 yielded identical PPG error though the former had higher R2, but the question remains: why should one think that the latter method - what has no particular bone to pick with AI (or any other player) and what directly incorporates on-court performance - would rank him decisively lower than the former? And might it be because the former gives positive weight to MPG, beyond what theory might suggest is justified?

MP -0.04221383 0.1703430321

permaximum wrote:You didn't have any problem with an invalid (but reliable) metric such as WS or too noisy RAPM aka "Nick Collison metric" "Amir Johnson metric" goes on an on.

If one is interested in the performance of a particular player, an elite player, for whom there are years and years of data of thousands and thousands of possessions, and one is generally persuaded as to the superiority of +/- approaches (as any right-thinking person should be) why would one not prioritize estimates that are directly (and serially) informed by these actual on-court contributions rather than a synthetic approximation, based on box-score regression, no matter if "on average" it proves better league-wide?