APBRmetrics

Maybe what I am seeing from these checks is mostly noise. But what do you do then? Great point, Crow. Yes, I agree that you can use Lineup APM minus individual APM to measure synergy. But as you noted, there often is not enough data points to draw a conclusion, because the number of lineup combinat...

Only the extreme starting lineups are near 1 point of synergy up or down (per game or per 100 possessions?) and only a few starting lineups play a full 1/3rd of the game. Is it possible to compute the average absolute lineup synergy for all lineups, minutes weighted? The simple average absolute lin...

The article's results for synergy for starting lineups show no more than a 10% change from sum of separate player ratings to combined lineup rating. So essentially is the article saying player synergies are pretty low and not that important? Or less sweeping, that experienced net synergies in actua...

Crow wrote:What is the average lineup impact rating of the average lineup played in the league? Is it close to 12-15?

Great guess! The average PORP across our entire data set is 2.82pts, or 14.1 per lineup.

I have a question about synergies of abilities with themselves. For low probability events, like steals, is it an assumption of your model that they have positive synergy? In other words, is this just a consequence of the form of your model, and the second derivative of the cdf of the normal distri...

Do you have any opinion / view based on training & experience about the value of computing blended metrics for decision-making instead of going with a single metric? Say SkillPM and RAPM or a more involved blend with additional metrics? Is this potentially or likely an optimal strategy or mainl...

What if you have a 20%-winning team, and you add David Robinson and Tim Duncan? The Spurs did that and became a 70% winning team. Is there any way to predict these things? David Robinson, yes, because he had already played in the league. Tim Duncan, doubtful, since he was a rookie. But yes, if the ...

Do you have can comment on the appropriateness of regression to the mean as practiced by RAPM but not traditional APM and I assume not by SkillPM either? To what extent does this choice interrelate with whatever average observed variance between expected performance based on separate player ratings...

Have you systematically compared the overall values of SkillPM to RAPM or other APM or other boxscore stats? Would you be interested in presenting data on how well they do comparatively at predicting lineup performance? We have not yet. The focus of our paper is to introduce a framework that evalua...

Why is Batum such a high and popular choice from the free agent pool when he is not listed as top 10 on overall SPM or any of the separate skill lists? Is he well-rounded? Is his particular skill profile just particularly well-matched with the skill deficiencies of many team's best 4s, given that i...

Is it true that total synergy of a lineup would be the sum of the overall net synergies of 10 player pairs and 21 skill synergies per pair for a total of 210 synergies? No, the total synergy of a lineup is calculated as PORP(p1,p2,p3,p4,p5) - PORP(p1,rp,rp,rp,rp) - PORP(p2,rp,rp,rp,rp) - PORP(p3,rp...

(1) What is the baseline for a team of "replacement players", specifically a team of such would produce a score differential of what? I ask for to calibrate your "PORP". Assuming that a team of replacement players is, as one would expect, well below average, this places the valu...

Philip - Is there any reason to think that SPM doesn't have the same inherent weaknesses that make APM a poor tool? Namely, terrible issues with collinearity that lead to poor predictive ability? SPM will have the same issue with collinearity. We addressed this issue in our paper by using four year...

Is this to suggest that a team featuring Dwight Howard and Kevin Garnett would be worse than a team featuring Dwight Howard, all else equal? If yes, that philosophy would rock the basketball world. (Obviously, I'm using some extreme examples here, but you catch my drift, no?) It just means the sum ...