Quiet blogging lately for a variety of reasons. In today’s post, I’m going to spend some time parsing RegEM (Truncated Total Least Squares) methodology, in itself hardly a standard technique, but particularly quirky in the Mann et al 2008 implementation. In the analysis leading up to O’Donnell et al 2010, we ported the Tapio Schneider […]
In a recent post commenting on Rich Muller’s lecture of March 19, 2011 (here) – of which the Climategate portion is more or less the same as his Oct 14, 2010 lecture (online here), John Cook observes: It’s clear that “Mike’s Nature trick” is quite separate to Keith Briffa’s “hide the decline”. Muller has taken […]
Two comments from UC on smoothing CET using Mannian smoothing, a technique peer reviewed by real climate scientists (though not statisticians). I think these coldish years do matter, maybe now there will be some advance in smoothing methods. mike writes (1062784268.txt) ( I think this is somewhat related to CET smoothing (?) ) The second, […]
load MBHsmooths1.txt % http://www.climateaudit.info/wp-content/uploads/2009/11/mbhsmooths1.txt % MBHsmooths1 = [ Year AnnualRecon Instrumental MB98SmoothTrick MBH98SmoothNoTrick MBH99SmoothTrick MBH99SmoothNoTrick ] [B98,A98]=butter(10,2/50); % ’50 year lowpass’ in98=MBHsmooths1(401:981,2); % Annual Recon MBH98, %source: % http://www.nature.com/nature/journal/v430/n6995/extref/FigureData/nhmean.txt , % col 2 Trick=MBHsmooths1(982:996,3); % pad with instrumental (1981..1995) .. % source: % http://www.nature.com/nature/journal/v430/n6995/extref/FigureData/nhmean.txt % col 3 out98t=flipud(filter(B98,A98,flipud([filter(B98,A98,[in98;Trick;zeros(100,1)])]))); %..then smooth % Note that filter.m initializes […]
Date: 16 Nov 1999, Phil I’ve just completed Mike’s Nature trick of adding in the real temps to each series for the last 20 years (ie from 1981 onwards) amd from 1961 for Keith’s to hide the decline. Date: 22 Dec 2004, mike No researchers in this field have ever, to our knowledge, “grafted […]
Let’s continue Mann 2008 – Replication with EIV. To run regreclow.m and regrechigh.m you’ll need files climate, eofnumb, and proxyN, where N runs from 1 to 19. I’ve run prepinputforrecon.m with required folder structure (C:\holocene\s1\zuz10\work1\temann\ etc.) in my computer. After that I did run regrechigh.m in folder C:\holocene\s1\zuz10\work1\temann\zzrecon1209\nhnhscrihad\highf and regreclow.m in folder C:\holocene\s1\zuz10\work1\temann\zzrecon1209\nhnhscrihad\lowf The regem […]
UC writes in that there’s another Mannian problem: And GRL08 ( http://www.meteo.psu.edu/~mann/shared/articles/MannGRL08.pdf ) is the prologue. Tried this new smoother ( http://www.meteo.psu.edu/~mann/smoothing08/lowpassadaptive.m ) with HadCRUT monthly and f=0.0104, [smoothedbest,w0,w1,w2,msebest] = lowpassadaptive(HadM, 0.0104); got this figure, But the weights are [w0 w1 w2] ans = 0.4100 0 0.5500 Surprisingly, this does not agree with the text, […]
%%%% Matlab version of Hockey Stick % %Mann, M. E., R. S. Bradley, and M. K. Hughes (1998), Global-scale %temperature patterns and climate forcing over the past six centuries, %Nature, 392, 779– 787. % %Mann, M. E., R. S. Bradley, and M. K. Hughes (1999), Northern %Hemisphere temperatures during the past millennium: Inferences, uncertainties, %and […]
I then compared verification statistics for the different reconstructions as shown below. OLS yielded much the “best” fit in the calibration period, but the worst fit in the verification period. If OLS is equivalent to ICE, it actually finds the best fit (minimizes calibration residuals), and in proxy-temperature case makes the most obvious overfit. Let […]
There’s an interesting knock-on effect from the collapse of MBH98 Figure 7 (see here and here). See update from UC in May 2011 below in which he did a “bit-true” replication. We’ve spent a lot of time arguing about RE statistics versus r2 statistics. Now think about this dispute in the context of Figure 7. […]
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