Sorry for OT Steve.

The parallel with econometrics is something I’ve often thought about when reading up on the latest “statistical” methods used in a climate science paper being dissected. Econometricians are the stewards of the analytical methods used in economics. As a consequence these methods are less likely to be hijacked by economists with political agendas.

Steve: ? This article has been referred to in almost every post. The chronology was done using corridor standardization and this is what accounts for the chrnoology difference – this point discussed in one of the early posts.

I understand one should dig the CA and literature for oneself to find out, but at the same time this (and similar) question (even if trivial for those who know the story from A to Z) might be informative to other CA readers as well, because surely many are like me new to the problem, but would like to know more. A brief hint would be greatly appreciated.

Steve: H and S use corridor standardization which, as a method, removes centennial variability. Briffa’s RCS has centennial variability, but the extent to which it contains artifacts in any case is the issue.

When using Google Earth, it always helps to turn the altitude record on (then you can easily figure out the river flow directions). I also tend to use the UTM gridding to locate and pinpoint areas and spots. Similarly, using the metric system, as the Russians do, reduces “hunt” time for specific areas

Look at the map in Fig. 1 of Hantemirov and Shiyatov 2002. There are all three rivers and sampling sites. You may then compare it with Google Maps – they are rather small and therefore not named. All three flow from North to South.

No one could be more frank, more painstaking, more free from subjective bias or parti pris than Professor Tinbergen. There is no one therefore so far as human qualities go, whom it would be safer to trust with black magic. That there is anyone I would trust with it at this present stage or that this brand of statistical alchemy is ripe to become a branch of science, I am not yet persuaded.

Does Briffa’s RCS rise above “statistical alchemy”? That’s the question.

The selection criteria and how that process should properly be performed is the all important issue and should be dominating the discussion. And that is why I get so turned-off when the discussion veers off into hurt feelings. Cherry picking is cherry picking, whether intentional or unintentional, and it carries a statistical price. Without an a prior selection criteria, the selection has to be considered cherry picking, whether performed by a saint or a not-so-saintly someone.
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Did Briffa “randomly” pick Schweingruber sites to add – right now, we have no way of knowing?

Advocates at realclimate and elsewhere urge us to defer to Briffa’s choices. If Briffa’s articles are to be viewed as a branch of prophetic or oracular literature, then followers are, of course, entitled to defer to his choices.

However, if Briffa’s articles are to be considered as scientific articles, then the selection criteria need to be clearly stated and it should be possible to verify the choices

download.file(“http://data.climateaudit.org/data/tree/schweingruber.details.tab”,”temp.dat”,mode=”wb”); load(“temp.dat”)

then do something like:

temp = details$lat>60 & details$long>88 & details$long<112
details[temp,]

http://www.eoearth.org/article/Tree_rings_and_past_climate_in_the_Arctic

“…tree-ring chronologies were highly correlated across distances up to 200 km (up to 500 km in northern regions)..”