OhayoKD wrote:f4p wrote:so before i go any further, am i reading this table correctly?

they put in the metric of choice, use it to predict, and the RMSE represents the average error on the team net rating?
so like they use EPM, guess +2.48 net rating and then on average, since the RMSE is 2.48 (let's just assume RMSE and MAE are close enough for government work here), the team ends up being either a 0.0 (41 wins) or a +4.96 (54 wins)? so if they plug in WS48 and guess +2.48, it could be -0.37 (40 wins) or 5.35 (55 wins)?
Seems about right, yeah. Though maybe someone whose good at this stuff like unibro can check we're interpreting this properly
so this seems to get at the point i was talking about in our other back and forth about all of these metrics:
...but is still going to be a struggle where i think the error bars (i.e. who actually gets the credit from the lineups) probably exceed the differences we are talking about...
setting aside PER for a second, which isn't even trying to predict anything, the error on EPM is 2.48 and the error on BPM is 2.7 and for WS48 is 2.85. the difference in their errors is an order of magnitude smaller than the error. that's a difference (from EPM) of about 0.6 wins for BPM and 1.0 wins for WS48, presumably against a background guess of 41 wins for the average team. and comparing to RPM basically eliminates any difference with BPM and makes the difference with WS48 about 0.7 wins. these are small differences. EPM isn't God talking to us on a mountain, except instead of the 10 commandments, he's giving us his top 10. and BPM/WS48 isn't a shirtless drunk guy yelling at the end of the bar. even PER manages to trip and fall, without even trying or being the same thing, into only about a 2 win difference with EPM and 1.6 win difference with RPM. the overlap of the predicted value for individual players on these things is going to be pretty substantial and leave us well within the zone of interpretation of what matters more for each player. and of course, the RAPM/PIPM stuff is inbetween the BPM and WS48 errors.