Hockey sticks, principal components, and spurious significance

@article{mcintyre2005HockeySP,
  title={Hockey sticks, principal components, and spurious significance},
  author={stephen. mcintyre and Ross McKitrick},
  journal={Geophysical Research Letters},
  year={2005},
  volume={32}
}
The “hockey stick” shaped temperature reconstruction of Mann et al. (1998, 1999) has been widely applied. However it has not been previously noted in print that, prior to their principal components (PCs) analysis on tree ring networks, they carried out an unusual data transformation which strongly affects the resulting PCs. Their method, when tested on persistent red noise, nearly always produces a hockey stick shaped first principal component (PC1) and overstates the first eigenvalue. In the… 

Comment on “Hockey sticks, principal components, and spurious significance” by S. McIntyre and R. McKitrick

[1] McIntyre and McKitrick [2005] (hereinafter referred to as MM05) point out a bias in the Mann et al. [1998] (hereinafter referred to as MBH98) Northern Hemisphere temperature reconstruction, one

Comment on “Hockey sticks, principal components, and spurious significance” by S. McIntyre and R. McKitrick

[1] We analyse a climate simulation of the last millennium to check whether the ‘‘artificial hockey stick’’ (AHS) effect introduced by biased centering has a significant bearing on the performance of

Reply to comment by Huybers on “Hockey sticks, principal components, and spurious significance”

[1] McIntyre and McKitrick [2005a] (hereinafter referred to as MM05) showed that the actual Mann et al. [1998] (hereinafter referred to as MBH98) PC method used an unreported short-centering method,

Comment on “Hockey sticks, principal components, and spurious significance” by S. McIntyre and R. McKitrick

Climate reconstructions based on proxy records require steps of standardization of the different series prior to their calibration to instrumental data. In a recent publication in GRL, McIntyre and

Elementary Reconstruction of the Hockey Stick Curve : Discussion of Paper by Li , Nychka and Ammann

The paper by Li, Nychka and Ammann (2010) has exemplified the power of Bayesian Hierarchical Models to solve fundamental problems in paleoclimatology. However, much can also be learned by more

Reply to comment by von Storch and Zorita on “Hockey sticks, principal components, and spurious significance”

[1] Von Storch and Zorita [2005] (hereinafter referred to as VZ) concur that the Mann et al. [1998] (hereinafter referred to as MBH98) principal component (PC) method ‘‘very often shows a hockey

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McKitrick – Discussion of McShane and Wyner

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As McShane and Wyner (2010) observe, there are formidable statistical problems in “reconstructing” past temperatures from networks of so-called “proxy” data with weak “signal” and complicated

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Corrections to the Mann et. al. (1998) Proxy Data Base and Northern Hemispheric Average Temperature Series

The data set of proxies of past climate used in Mann, Bradley and Hughes (1998, “MBH98” hereafter) for the estimation of temperatures from 1400 to 1980 contains collation errors, unjustifiable
...

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The differences between the results of McIntyre and McKitrick [2003] and Mann et al. [1998] can be reconciled by only two series: The Gaspé cedar ring width series and the first principal component

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TLDR
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