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Benchmarking from VZ Pseudoproxies
Von Storch et al 2004 advocated using climate models to generate pseudoproxies to test the properties of proposed multivariate methods. Hardly unreasonable. I might argue that these are long-winded...
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RegEM
RegEM has reared its ugly head again in Mann’s review of Burger and Cubasch. An EM algorithm was one of the very first things that I tried when I started doing this a couple of years ago. When I tried...
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Jean S on Rutherford et al 2005
Jean S has sent the following longer contribution on Rutherford et al 2005. I always appreciate Jean S’s thoughtful comments (which is no secret to readers here). So enjoy. JeanS: Now since the review...
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More on "Naturally Orthogonal"
I realize that not all CA readers are interested in multivariate methods and that dendroclimatologists want to “forget the math”, but I find it interesting to try to relate dendro and paleoclimate...
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Re-Visiting RegEM: Rutherford et al 2005
Mann et al 2007 is a new RegEM version, replacing the RegEM calculations of Rutherford et al 2005. The logic is not entirely self-contained and so I re-visited some of our previous comments on...
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Mann and Perfect Reconstructions
I finally turned over a few stones in Mann’s EIV reconstructions, little suspecting the perfection that awaited me in the cave using the simple and unassuming alter ego shglfulihad_smxx. The figure...
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Smerdon et al 2008 on RegEM
Smerdon et al 2008 is an interesting article on RegEM, continuing a series of exchanges between Smerdon and the Mann group that has been going on for a couple of years. We haven’t spent much time here...
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Porting RegEM to R #1
I’ve transliterated relevant Tapio Schneider code into R (pttls.m) and parts of regem.m that seem relevant at present. Jeff Id has extracted a variety of intermediates from his Matlab run and I’ve...
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RegEM PTTLS Ported to R
I’ve now ported my emulation of Schneider’s RegEM PTTLS to R and benchmarked it against Jeff’s Matlab as shown below. I caution readers that this is just an algorithm. There are other ways of doing...
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Why did Steig use a cut-off parameter of k=3?
A question that Jean S inquired about before we were so rudely interrupted. The expanation in Steig et al was: Principal component analysis of the weather station data produces results similar to those...
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