APBRmetrics

[greyberger]

Wow kind of takes the air out of Kevin Love's 30-30 game. That Nash and Gerald Wallace had better nights is understandable, especially with the difference between 106 possessions and 87 or 88... but that Micheal Beasley might have been the hero of that game is something that went entirely overlooked in the media.

I'm not sure I would have come to that conclusion myself, but there's an case there. Without Beasley's scoring contribution the Wolves would have been 28/72.

[DSMok1]

[DSMok1]

Another sample of single-game ASPM: Last night's Heat-Suns game:

[DSMok1]

Single game for the Thunder/Celtics Yesterday:

[Italian Stallion]

I'm a huge Knicks fan. I was looking at some adjusted +/- data from another source and noticed that Raymond Felton looks terrible by that metric so far this year.

That doesn't jive with box score data, personal observation, the Knicks much improved performance (I realize that Fields has had a huge positive impact) or the fact that IMO he's clearly better than Duhon was last year.

Does anyone have an explanation for why he's rating so poorly so far?

IMO something is amiss

[greyberger]

Well, if you mean just-this-year-so-far, isn't APM over a 30 game sample very noisy? I'm not sure APM is much of an improvement over looking at raw +/- in small samples.

[DSMok1]

[Crow]

Traditional Adjusted +/- for less than half of a season is of very limited use by itself but not entirely useless in my opinion.

The adjusted +/- at basketballvalue.com is non-regularized and likely over-fit in cases, especially at the extremes, which is where Felton falls in this estimate, and in small sample sizes. Felton's extremely negative rating probably has some significant relationship with Fields' extremely positive rating.

Ordinarily I'd be fairly comfortable using the traditional 2 season Adjusted +/- (even though I prefer the regularized and longer term versions) but he was traded and that could change his play and team impact so I'll look further into the current season data.

His raw team defensive efficiency on / off is the worst on the team (-9 per 48 minutes) and actually 8th worst in the league among those having played over about 15 minutes per game. His team defensive efficiency while on the court is also tied for the team worst with Amare among those playing more than 10% of team minutes. This is probably a main cause of the poor Adjusted +/-.

Felton's 2 season bv.com Adjusted +/- (really about 1.4 seasons) is still quite weak but no where near his extreme 1 year number. It has far lower stated / estimated average error. Whether he eventually ends up the season neutral or positive on 2 season Adjusted +/- like on the previous long timeframe Adjusted +/- ratings or at least a lot less negative or not may come down to how negative his impact on team defense really is this season and how much of the extreme rating is noise / special circumstance / collinearity.

The raw +/- shows Felton-Fields-Stoudemire have played 716 minutes together and are +59 for a nice enough average of +4 per 48 minutes. Looking at selective pair data among them and finding the differences between it and the triplet data I find that Felton-Stoudemire on the court without Fields have been -4.4 per 48 minutes in 238 minutes while Fields-Stoudemire without Felton are +21 per 48 minutes in 84 minutes. If you want to think about how good or bad Fields or Felton are respectively using +/- raw or Adjusted, it is worth noting that these specific minutes are having a pretty big impact separating them and so it would be worth reviewing on video of these different sets of minutes and a range of discrete individual and team boxscore stats associated with them to see what detail you can find about what specifically is going on and why it is producing very different scoreboard results- so far.

These are very small minute samples and of course might be creating overly extreme impressions that will moderate with time, but some of what is happening might well continue if unexamined and left unchanged It is certainly worth trying to get a handle on rather than just waiting, hoping or ignoring. I haven't done a thorough study... but I can quickly see the offensive and defensive efficiency splits which reveal that Fields-Stoudemire without Felton has shown major improvements on both sides of the court compared to the averages for the trio together while Felton-Stoudemire without Fields slips on both but more so on offense compared to the trio together.

Adjusted +/- has limitations, especially on very short-term data on a non-regularized version, but consideration of the current data alongside previous Adjusted +/- estimates and lots of other information can help with creating a decent big picture and helps direct further research (on Felton himself, Felton's impact compared to Fields overall and with and without each other.)

Of course the full reality is more complicated. Other teammates need some attention too (especially the weak at SG Douglas and Mason) as do the play calls and the mix of game situations faced by the player combinations (which might be notably different in ways beyond the quality of the other players on the court and beyond what a basic version of Adjusted +/- adjusts for). But raw and Adjusted +/- data can help some in the broad search for a deeper understanding.

Felton's relatively good performance on individual boxscore stats is another perspective about his impact, to be considered alongside +/- data. Using one without the other seems less strong / unwise to me. Looking at various splits of that individual data including when the player is in various combinations / lineups with key others probably would help even more.

Shot defense is not in simple boxscore based metrics so you either need to look at raw and Adjusted +/- or include counterpart data or both to consider that large element of the game.

[Italian Stallion]

Has anyone tried to incorporate the changed distance for 3 pointers into any of their studies?

It was shorter from 1994-1997 and players like Jordan and a few others may have benefited relative to others

[Mike G]

Mookie Blaylock got more than half of his career 3-ptrs in this 3-year interval. It also happened to fall in the middle of his career, age 27-29. He had easily his 3 best TS% seasons.

But both his PER and his WS/48 were higher the previous year, '93-94, than they were the next 2 years. His career by every measure topped out in '97, and then the 3-pt rug was pulled from under him, and he was in instant decline.

Even this extreme example of 3-pt feasting didn't really create his stardom, but just had him shooting more 3's. Jordan, on a smaller scale, also made these short 3's much better. But his PER and WS rates didn't jump appreciably.

A rule change, whether a short arc, a hand-check rule, the no-charge circle, is an equal opportunity invitation to adjust your game. Some are more adaptable than others.
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36% of all statistics are wrong

[Italian Stallion]

[DSMok1]

I had to update the primary Advanced SPM spreadsheet because Basketball Reference changed the columns in the team table. I also caught a few minor bugs.

Update here: Google Docs

That spreadsheet includes ASPM, ASPM projections, salary analysis, single-game predictions, single-game analysis, and player comparisons.
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GodismyJudgeOK.com/DStats
Twitter.com/DSMok1

[inkt2002]

Looks great!
Thanks for posting.

[Italian Stallion]

Crow,

By the way, thanks for that detailed analysis.

[Crow]

Ok, thanks for the follow-up acknowledgment.