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 Rutherford et al here here here here . I’m going to reprise two issues today: Collation Errors, a small but amusing […]
Julien Emile-Geay from Judith Curry’s university – who, together with Kim Cobb, is teaching a course on the Hockey Stick – has joined our debate with a forceful criticism of Craig Loehle’s recent paper. While Emile-Geay seems to be a lively young man with some very cordial comments about CA here and his comments are […]
I recommend that CA readers visit UC’s blog for some interesting discussion. (BTW UC visited Toronto recently and we had a nice dinner.) UC posted the following interesting figure on Unthreaded as follows: BTW, got interesting result when I replaced Temperature PCs with solar in MBH98 algorithm. Similar RE values as in the original, and […]
In a recent post, I’ve indicated that IPCC authors seems to have invented a “test” for long-term persistence that is nowhere attested in any statistical literature and, if I’ve interpreted what they’ve done correctly, appears to be a useless test. Jean S and I have made a few references to the Review Comments on the […]
In browsing AR4 chapter 3, I encountered something that seems very strange in Table 3.2 which reports trends and trend significance for a variety of prominent temperature series (HAdCRU, HadSST, CRUTem). The caption states: The Durbin Watson D-statistic (not shown) for the residuals, after allowing for first-order serial correlation, never indicates significant positive serial correlation. […]
We’ve had a couple of discussions of dealing with end-points for smoothing. Here’s a little note about smoothing algorithms, which I think is pretty funny. It’s hard to imagine a note about smoothing algorithms being funny, but see what you think.
Over at realclimate, Mann has advocated a new “explanation” of the Divergence Problem raised by one of their readers in connection with IPCC AR4 Figure 6.10. Mann says that there is no Divergence Problem; he blames the reader for failing understand boundary constraints in smoothed series. Raising the Divergence Problem at realclimate was so blasphemous […]
Willis raised an interesting point about trying to invert series based on partial correlation coefficients with monthly temperatures. His post, together with UC’s response are collected here.
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 recipes to known statistical methodologies that you can read about in texts. I commented the other day on the form of Principal Components […]
Wilson and Luckman 2003 observe: The first PCs from the RW and MXD PCA are naturally orthogonal (r = —0.006) over the 1900—1991 period suggesting the in’?fluence of different forcing mechanisms upon these parameters. They move on without pausing here, but this point should not be left without a commentary. The issue here is one […]
Climate Audit 