[Mod Edit] Must Read: Drew Fustin Article on Deflategate Science

[QuantumMechanic]

What it means is that if Walt Anderson used a gauge that closely resembled the calibration of the gauge the Patriots used, he should have measured the Patriots balls at 12.0. The fact that he measured them at 12.5 means the gauge he was using (which he recalls as the logo gauge) would have been reading around 0.5 higher. Not coincidentally, the Logo gauge consistently measures ~.5 higher than the other gauges. This means Walt had to have used the Logo gauge, and the simulation using the Logo gauge shows that the half-time measurements of Patriots footballs are entirely explained by the effect of weather on air pressure.

Oh, ok. I see what you're saying, now. So JJ measures the balls after gloving at 12.6psig. When the ball equilibriates to room temp in 15-20 minutes the pressure has dropped to 12.0psig. Now the balls come to Anderson, whose gauge measures them at 12.5psig but since we're assuming JJ's gauge read true we thus assume Anderson was using the logo gauge. Makes sense as far as it goes.

However, what grounds do we have to assume that JJ's gauge reads true?

 

[Danger Zone]

http://profootballtalk.nbcsports.co...inner-disagrees-with-science-in-wells-report/

“I believe the data available on ball pressures can be explained on the basis of physical law, without manipulation,” MacKinnon writes. “The scientific analysis in the Wells Report was a good attempt to seek the truth, however, it was based on data that are simply insufficient. In experimental science to reach a meaningful conclusion we make measurements multiple times under well-defined physical conditions. This is how we deal with the error or ‘spread’ of measured values. In the pressure measurements physical conditions were not very well-defined and major uncertainties, such as which gauge was used in pre-game measurements, affect conclusions. Finally, the claim of a statistically significant difference in pressure drop between the two team balls regardless of which gauge was used did not account for the fact that the Colts balls were apparently measured at the end of halftime since the officials ran out of time and made only four measurements – in other words, the Colts balls were measured after the Patriots balls and had warmed up more. For the above reasons, the Wells Report conclusion that physical law cannot explain the pressures is incorrect.”

 

[wahwho]

There's also a question of if the order of events was Measure Pats -> Measure Colts -> Inflate Pats or Measure Pats -> Inflate Pats -> Measure Colts; if it's the latter, then the graphs and controls are way off. (There's an assumption that it was the former throughout the document but I don't think I ever saw a direct statement that it really happened that way. Maybe I missed it, though.)

For anyone who missed it, the Pats answered this question in their rebuttal today. It was Measure Pats -> Inflate Pats -> Measure Colts. That's a huge difference.

 

[jeffro]

I just noticed that Fustin points out (near the bottom of his report) that the football numbering in the halftime measurements do not seem to correspond to the order in which they were measured. If you try to order the measurements by ball number then there is no clear PSI/time trend. These measurements are FUBAR.