Letter to Daniel Marlow on Exponent Error

On June 29, I sent a letter to Ted Wells, notifying him of the erroneous description of key figures in the Exponent report, but did not receive any acknowledgement.  In the presumption that Daniel Marlow of Princeton is more likely to be concerned about the erroneous research record (as well as having obligations that the research record be properly presented) I sent him a similar letter today, copying lawyers Daniel Goldberg and Jeffrey Kessler.

Dear Dr Marlow,

I am an experienced data analyst and have followed the Deflategate controversy with interest.  I wish to draw the following material misdescription and error in the Exponent report to your attention.  Will Happer, who I am copying, knows me and can vouch for me.  I am also copying this to Daniel Goldberg and Jeffrey Kessler.

In Figure 27, Exponent stated that the Patriot and Colt footballs were “set with the Logo Gauge” at 12.5 psig and 13 psig respectively.

However, this description is erroneous. The transients in the figure can only result from the footballs being set with the Master Gauge (NOT the Logo Gauge)  at 12.5 and 13.0 respectively.

The incorrect description is very material, because, if the footballs had been set with the Logo Gauge – as stated in the figure, the transients would be lower and the time interval of potential intersection with observations would be increased to approximately 6 minutes even at the 67 deg F initialization temperature assumed in the Figure (the temperature most adverse to the Patriots).  After correcting the error, it can no longer be said that anomalous Patriot deflation exists regardless of assumption on gauges.

While both you and Exponent have argued that the Non-Logo gauge must have been used for Patriot measurements, this does not justify Exponent’s erroneous description of the procedures used in Figure 27 (and 30) or any conclusions drawn from that figure. I have  described the issue in more detail http://climateaudit.org/2015/08/07/exponents-trick-to-exaggerate-the-decline/.

I find it very troubling that judgements have already been made based on figures that have been incorrectly described.   I draw this to your attention in the belief that you will also be concerned and will feel obliged to take steps to correct the research record as soon as possible. Obviously, the Deflategate  controversy has drawn very attention and is proceeding to a difficult decision, a decision that, in my opinion, is made more difficult by the misrepresentation of these figures in the Wells Report. In my opinion, there is some urgency that you correct the record expeditiously if you concur with my analysis, as I anticipate that you will.

I previously drew this error to the attention of Ted Wells on June 29 without any effect, but hope that you will have more concern.

Regards,
Stephen McIntyre
Climate Audit​

———- Forwarded message ———-

From: Stephen McIntyre
Date: Mon, Jun 29, 2015 at 9:28 PM
Subject: Exponent Report
To: Ted Wells at Paul Weiss
Dear Mr Wells,

While there have been many criticisms of Exponent’s technical analysis, I wish to draw your attention to a material and highly important misrepresentation of methodology in their technical report.  The calculation of transients, used in the important analyses of Figures 27 and 30, is described as follows:

In recognition of the remaining uncertainty as to which gauge was used to measure the footballs pre-game and in the interest of completeness, similar tests were run using the Logo Gauge. The Logo Gauge was used to set the pressure of two balls to 12.50 psig (representative of the Patriots) and two balls to 13.00 psig (representative of the Colts). From each set (corresponding to each team), one ball remained dry while exposed to the game temperature and the other was wet.

For reasons set out in more detail at Climate Audit (http://climateaudit.org/2015/06/29/exponents-transients-bodge-or-botch/), it is impossible that the bolded statement is a correct description of Exponent’s actual methodology. To arrive at the dry Patriot transient illustrated in Figure 27,  the Logo Gauge would have had to have been set to ~12.81 psig. It appears more likely that a different gauge was used to initialize the footballs in the simulations illustrated in these figures.   If Exponent had used the stated methodology, they would not arrive at the results illustrated in Figures 27 and 30.

The misrepresentation is material and warrants an immediate corrigendum,  together with retraction of technical analysis depending on this mistake. It is by no means the only statistical error in Exponent’s report, but is somewhat distinguished by it being an actual misrepresentation as opposed to a methodological critique.

I have considerable experience in statistical analysis.  I have made presentations to a panel of the U.S. National Academy of Sciences, a subcommittee of the U.S. House of Representatives and my work has been covered on the front page of the Wall St Journal, by CNN and Fox News and internationally. In 2010, the New Statesman magazine in the U.K. recognized me as one of “50 People Who Mattered” in 2010.

Regards,
Stephen McIntyre
Climate Audit
www.climateaudit.org

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