“Noisy” covariance matrices have been discussed here on many occasions in a variety of contexts, largely because the underlying strategy of Mannian methods is to calculate the covariance of everything to everything else and then calculate verification stats using methods that ignore the data mining that effectively takes place with huge covariance matrices. Steig et […]
Roman Mureika perceptively observed about 10 days ago that the AWS reconstruction consisted of only 3 PCs. Jeff Id has extended this to observing that the AVHRR reconstruction consists of only 3 PCs. Jeff’s demonstration of this is correct, but a little awkward. I’ll show an alternate demonstration which shows a useful linear algebra property […]
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 regressions and infills. The apparent convergence to three PCs noted by Roman is still pending as a highly interesting phenomenon. […]
Standardization in Mannian algorithms is always a bit of an adventure. The bias towards bristlecones and HS-shaped series from the impact of Mann’s short segment standardization on his tree ring PCs has been widely publicized. Smerdon’s demonstration of defects in Rutherford et al 2005, Mann et al 2005 and Mann et al 2007 all relate […]
Andrew Sullivan, a well-known writer, has been blogging since 2001 and won the 2008 Best Blog award (displayed at his site.) In November, prior to this competition, he published an excellent essay on blogging in the Atlantic Monthly, one that I read at the time and meant discuss. Give it a read. While his lessons […]
My squash club has wonderful squash doubles pro-am that runs over the first few weeks of February. The pro at our club, Eric Baldwin, does a great job organizing and it is well supported by the pros around Toronto, which is an very active squash community. Jonathon Power is now a member, as is Gary […]
Ross writes: Has Gavin posted on his IJOC paper? [SM – yes. At RC today.] I will head over tomorrow to have a look. Not today–it’s very sunny here and the ice rink beckons. I am not sure how replication plays into the issue, since I posted my data and code from the get-go. I […]
Full many a gem of purest ray serene The dark unfathomed caves of ocean bear: Full many a flower is born to blush unseen, And waste its sweetness on the desert air. Thomas Gray (English Poet, 1716-1771) From time to time, we here at Climate Audit have the opportunity to draw attention to otherwise obscure […]
More changes at 6 ocean stations at BAS listed here , together with a revised “credit” here. One of the 6 stations is Chatham Island, where I noticed a problem on June 13, 2008 when I was trying to replicate GISS methodology using Wellington NZ as an example. John Goetz pinned the erroneous source to […]
Many bemused blog readers know by now that Gavin Schmidt aka Mystery Man has taken a few hours off from his dedicated and long-standing interest in station data integrity to file a complaint to the University of Colorado about a post that Roger Jr wrote about the Gavin Affair. Gavin has refused Pielke permission to […]
Climate Audit 