Sunday, January 19, 2014

You want the truth…You can’t handle the truth…

Some of these problems just seemed the sort of errors that are caused by sloppy data handling concerning location labels, use of obsolete editions, unexplained truncations of available series, etc. Although such errors should have been spotted in the peer review process and they would adversely affect the quality of Mann’s conclusions they had a relatively small effect on the final results.

But McIntyre and McKitrick found one major error, an error so big that it invalidated the entire conclusion of the whole paper. A whopper of an error.

The error continues to be propagated throughout the AGW debate.  Despite it being proved false.  One graph shows it all…

Hockey Schtick

The key finding in the Wegman Report was that “Our committee believes that the assessments that the decade of the 1990s was the hottest decade in a millennium and that 1998 was the hottest year in a millennium cannot be supported by the MBH98/99 [the technical name of Mann's original Hockey Stick paper]”

The other conclusions of the Wegman Report are also very interesting; It listed the following conclusions:

Conclusion 1. The politicization of academic scholarly work leads to confusing public debates. Scholarly papers published in peer reviewed journals are considered the archival record of research. There is usually no requirement to archive supplemental material such as code and data. Consequently, the supplementary material for academic work is often poorly documented and archived and is not sufficiently robust to withstand intense public debate. In the present example there was too much reliance on peer review, which seemed not to be sufficiently independent.

Conclusion 2. Sharing of research materials, data, and results is haphazard and often grudgingly done. We were especially struck by Dr. Mann’s insistence that the code he developed was his intellectual property and that he could legally hold it personally without disclosing it to peers. When code and data are not shared and methodology is not fully disclosed, peers do not have the ability to replicate the work and thus independent verification is impossible.

Conclusion 3. As statisticians, we were struck by the isolation of communities such as the paleoclimate community that rely heavily on statistical methods, yet do not seem to be interacting with the mainstream statistical community. The public policy implications of this debate are financially staggering and yet apparently no independent statistical expertise was sought or used.

Conclusion 4. While the paleoclimate reconstruction has gathered much publicity because it reinforces a policy agenda, it does not provide insight and understanding of the physical mechanisms of climate change except to the extent that tree ring, ice cores and such give physical evidence such as the prevalence of green-house gases. What is needed is deeper understanding of the physical mechanisms of climate change.

Hockey Schtick

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You are not entitled to your opinion. You are entitled to your informed opinion. No one is entitled to be ignorant.

Harlan Ellison