Here’s a comment on handling of Preisendorfer’s Rule N in the code dump; I’ll post some further comments on Preisendorfer on Preisendorfer’s Rule N in a few days. There is NO source code showing the application of Preisendorfer’s Rule N to tree ring networks – a battleground issue, if you will. There is some source code showing the application of a procedure described as "Rule N" to determine the number of temperature PCs to retain, but the procedure in the source code is not consistent either with Rule N of Preisendorfer [1988] or with the procedure illustrated for tree ring networks at realclimate here Continue reading →
I’ve written on a number of occasions on Briffa’s Polar Urals reconstruction, which is used in nearly every multiproxy reconstruction, no doubt because of its uniquely cold MWP. It’s one of the key series in Crowley and Lowery [2000] and Jones et al [1998]; it’s not as important in MBH98-99 (which is more or less just the bristlecones in the MWP. Here’s some information from a relatively inaccessible source: Shiyatov, S.G. Reconstruction of climate and the upper treeline dynamics, Publications of the Academy of Finland 6/95, 144-147. Continue reading →
I’ve commented before on the lack of independence between authors in the supposedly "independent" multiproxy studies: Mann et al [1998, 1999], Jones et al [1998], Mann and Jones [2003], Crowley and Lowery [2000], Briffa et al [2000]. I’ve mentioned in passing that the proxies themselves are not independent, but not provided lists to show the extent of overlap. I’ve provided this information below for a few of the Hockey Team Studies. MORE
One of the big selling points of Crowley and Lowery [2000] was the “non-synchroneity of temperature change”. One of the key series in showing this was Zhu [1973]. I located Zhu [1973] today. It was great fun, not least for Zhu crediting the teachings of Chairman Mao for inspiring his work. I even reminisce a little about 1968. Continue reading →
US Congressman Joe Barton expressed some thoughts here (link courtesy of Jerry Brennan).
I reported recently on that the recently archived (July 2005) source code multiproxy.f shows that the cross-validation R2 statistic was calculated and not reported.
Today, I’m merely going to summarize some collation details from my inspection of the code, listing input files, output files and providing a lexicon of variables. The source code requires a variety of input files which do not exist at the existing data archive. Under the circumstances, I would have expected punctilious archiving, but this hasn’t happened. In addition, if one crosschecks the steps documented in the new source code with the replication issues listed here , rather few of them are covered in this current code dump.
I’ll return to this in a future post, with a particular consideration of Preisendorfer’s Rule N. Continue reading →
In our GRL article, we pointed out that MBH98 had misrepresented their principal components methodology as being "conventional", when it wasn’t.
At realclimate , they argued that it was an alternative centering "convention".
Continue reading →
In some of our discussions of data archiving, the principal rationalization of a researcher’s not archiving data at recognized permanent archives (such as WDCP) has been the argument that they should be able to maintain confidentiality for a period of exclusive use.
I’ve noticed that some researchers have established password-protected private archives, to which some but not all interested researchers can have access. This seems like a strange sort of confidentiality to me. As an analogy, legal advice to a client is privileged, but the client would waive the privilege if he showed the advice to a bunch of his friends. I realize that the analogy isn’t perfect, but I think that there is an issue here.
I can somewhat understand the argument for data being private for a limited period (although I would be pretty tough on enforcing the terms of the contract), but I’m having trouble understanding the rationale for password protected sites with access limited to the initiate. I’ve tried unsuccessfully to get access to the European data at SO&P, managed by Briffa and Osborn. We can only hope that Briffa’s concept of a reasonable period of exclusive use will be less than 22 years.
Continue reading →
Let no one say that I don’t give credit where credit is due. Keith Briffa, yes Keith Briffa, has archived 13 tree ring site chronologies at WDCP: it’s only 17 years since publication and 22-24 years since collection, but who’s counting? Continue reading →
“Lasciate ogni speranza, voi ch’entrate…”
If you look at the footer of any page, you’ll see the current statistics on how many spam comments have been dealt with by Spam Karma 2 since I installed it on the 9th of July.
As you can see, managing even a moderately successful weblog like this one would be a full time task without automated help like this.
I have also upgraded the Spam Karma 2 software to the latest version.
