[BostonCard]

[quote author=CTcard link=topic=15920.msg176255#msg176255 date=1476726793]
[quote author=CrazedZooChimp link=topic=15920.msg176253#msg176253 date=1476726398]

I'm actually surprised the "recent" model has us ranked so high, seeing as we're 1-2 in our past three games with an ugly score differential.

Indeed, sometimes the ratings Sagarin posts are bizarre enough that I suspect actual calculating errors.
Of course since he doesn't publish exactly what he does, no one can check.
[/quote]

Sagarin's highly flawed models have been reverse engineered by various groups over the years. The "Predictor" model basically consists of weighted linear regression using almost-uncapped score margins. Sagarin's season ending ratings have retrodictive value, but any objective analysis (measuring deviation from the final score) concludes that the consensus opening and closing betting lines are far stronger predictors. The problem with Sagarin's (and others') predictive models is primarily that they are purely statistical with no adjustments for factors that may have distorted previous results (e.g. lucky plays, officiating errors, personnel changes) or will impact future results (e.g. injuries, weather conditions).
[/quote]

"All models are wrong. Some are useful."

-- George P. Box

Of course betting lines will be better than any computer system, because if computer models were better, you would have a chance at arbitrage. In that sense, the efficient market hypothesis applies to betting markets. The betting models incorporate information from the computer ones, plus all the subjective matters you mention.  There is no way to systematically apply an adjustment based on external factors to a computer model, so any such application would be ad hoc (say, deducting a couple points because of McCaffrey's injury), but how do you determine the magnitude of the deduction?

[s]Sagarin is a tool[/s]. The Sagarin rating system is a tool.  It can offer some insight about games.  As long as you understand its intrinsic limitations, it is still useful, which is about all you want from something like that.

Beats the hell out of Jon Wilner's twisted insights in his rankings.

BC

[BostonCard]

[quote author=CTcard link=topic=15920.msg176255#msg176255 date=1476726793]
[quote author=CrazedZooChimp link=topic=15920.msg176253#msg176253 date=1476726398]

I'm actually surprised the "recent" model has us ranked so high, seeing as we're 1-2 in our past three games with an ugly score differential.

Indeed, sometimes the ratings Sagarin posts are bizarre enough that I suspect actual calculating errors.
Of course since he doesn't publish exactly what he does, no one can check.
[/quote]

Sagarin's highly flawed models have been reverse engineered by various groups over the years. The "Predictor" model basically consists of weighted linear regression using almost-uncapped score margins. Sagarin's season ending ratings have retrodictive value, but any objective analysis (measuring deviation from the final score) concludes that the consensus opening and closing betting lines are far stronger predictors. The problem with Sagarin's (and others') predictive models is primarily that they are purely statistical with no adjustments for factors that may have distorted previous results (e.g. lucky plays, officiating errors, personnel changes) or will impact future results (e.g. injuries, weather conditions).
[/quote]

"All models are wrong. Some are useful."

-- George P. Box

Of course betting lines will be better than any computer system, because if computer models were better, you would have a chance at arbitrage. In that sense, the efficient market hypothesis applies to betting markets. The betting models incorporate information from the computer ones, plus all the subjective matters you mention.  There is no way to systematically apply an adjustment based on external factors to a computer model, so any such application would be ad hoc (say, deducting a couple points because of McCaffrey's injury), but how do you determine the magnitude of the deduction?

[s]Sagarin is a tool[/s]. The Sagarin rating system is a tool.  It can offer some insight about games.  As long as you understand its intrinsic limitations, it is still useful, which is about all you want from something like that.

Beats the hell out of Jon Wilner's twisted insights in his rankings.

BC