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digger
09-06-2012, 06:08 PM
http://www.grantland.com/story/_/id/8284393/breaking-best-nfl-stats

Football's Pythagorean Theorem

In a Sentence: Point differential is a better indicator of future winning percentage than winning percentage itself.
How It Works: Created by Bill James for baseball and modified for football in the early '90s by current Houston Rockets general manager Daryl Morey, the Pythagorean theorem (or "Pythagorean expectation") is a formula that translates a team's points scored and allowed into an "expected" winning percentage. That formula isn't exactly for the faint of heart:
Points For<sup>2.37</sup> / (Points For<sup>2.37</sup> + Points Against<sup>2.37</sup>)
As an example, let's take the 2011 Chiefs, who went 7-9 while scoring 212 points and allowing 338. Our formula is 212<sup>2.37</sup> / (212<sup>2.37</sup> + 338<sup>2.37</sup>) = 0.248. That's the Chiefs' expected winning percentage from their point differential, and if we multiply it by 16 games, we get a total of just 4.0 wins. The Pythagorean theorem suggests that the Chiefs outperformed their true level of performance by three full wins.


See we did better last year. :banghead:

Baconeater
09-06-2012, 06:28 PM
Well three of our wins were gifts, so that sounds about right.

Just Passin' By
09-06-2012, 06:52 PM
When you've only got a 16 game sample size, and you've got several blowouts, especially when they go in both directions, the theorem doesn't really work.

whoman69
09-06-2012, 06:53 PM
What Bill's theory never takes into account is that teams are not always consistent.

BWillie
09-06-2012, 06:58 PM
When you've only got a 16 game sample size, and you've got several blowouts, especially when they go in both directions, the theorem doesn't really work.

Yeah I would take it with a grain of salt. But I would love to bet money against someone who thought the Orioles had a chance to win the AL East.

saphojunkie
09-06-2012, 07:06 PM
I'm guessing that any statistical analysis followed by an entire article explaining why there are discrepancies is a shitty one.

JoeyChuckles
09-06-2012, 07:18 PM
I'm guessing this poster is Bill Barnwell.

digger
09-06-2012, 09:25 PM
I'm guessing this poster is Bill Barnwell.
And you would be wrong. Just though it was interesting.:thumb:

Pasta Giant Meatball
09-06-2012, 09:51 PM
They got outscored by like 100 points the first 2 weeks, soooo. Like was said above a sample size that small is going to be extremely flawed.

NFL16
09-06-2012, 11:18 PM
When you've only got a 16 game sample size, and you've got several blowouts, especially when they go in both directions, the theorem doesn't really work.

Not quite sure about that. Blowouts in both directions would balance each other out and give a more accurate prediction, I believe.

Count Alex's Losses
09-06-2012, 11:19 PM
The Pythagorean theorem suggests that the Chiefs outperformed their true level of performance by three full wins.


Well, well, well.

Who was saying that ALL OFFSEASON?

LMAO

BigMeatballDave
09-06-2012, 11:27 PM
These things can't factor injuries.

Or replacement refs...

Just Passin' By
09-06-2012, 11:32 PM
Not quite sure about that. Blowouts in both directions would balance each other out and give a more accurate prediction, I believe.

Only if they were over the course of a long series of games. In a short series, like the 16 games in the NFL, you can't smooth out the edges of your data.

SNR
09-06-2012, 11:40 PM
This formula is fucking bullshit. I got out my calculator to find out the Chiefs' current expected winning percentage, but my calculator kept spitting the formula back out at me with an "ERROR" message. This shit doesn't work at all.

cdcox
09-06-2012, 11:54 PM
Pythagorean wins from year n-1 is a better predictor than WLT record in year n-1 for the record in year n. It's pretty much an indisputable fact.

jspchief
09-07-2012, 01:24 AM
These things can't factor injuries.

Or replacement refs...

Here we go again...

RippedmyFlesh
09-07-2012, 07:54 AM
I think stats can predict future performance in baseball much more so than football.
A baseball players career is longer so they are at a certain stat level for a longer period of time. Football players tend to go up and down more from a stat stand point.
In baseball stats can help you predict what will happen in football it is more why something happened than what will happen.