Comments on: Another Interesting Correlation Graphic

By: ChrisJ

ChrisJ — Sat, 27 Sep 2008 18:23:28 +0000

Sidebar- Could some explain the meaning of the bi-modality? Thanks. -chris

By: Pete Stroud

Pete Stroud — Fri, 26 Sep 2008 11:00:52 +0000

Surely Mann’s defence of Gore’s snows of Kilimanjaro claptrap that was judged completely erroneous by a British high court judge, must make even a rabid alarmist doubt the ‘Nobel Laureate’s’ scientific competence.

By: Steve McIntyre

Steve McIntyre — Fri, 26 Sep 2008 10:34:38 +0000

a Nobel Prize-winning scientist

Isn’t the proprietor of Climate Audit a “co-winner” of whatever prize that Michael Mann won? Maybe we can have a parade together.

By: Jean S

Jean S — Fri, 26 Sep 2008 07:47:11 +0000

Re: sean egan (#5), RegEM stands for "Regularized EM algorithm" by Tapio Schneider, see here. Not that I'm aware of. The problem with RegEM is that very little is known of its properties. However, one should stress that again (see old posts in CA and check publications here) Mann is using a modified version of RegEM as I observed here. If I were Tapio Schneider, I'd be quick to check that this unreported modification does not change the intended behavior of the algorithm...

By: Arthur Dent

Arthur Dent — Fri, 26 Sep 2008 07:44:59 +0000

Note that the IPCC won the Nobel Prize and I have seen many contributers to the IPCC referred to as ‘Nobel Prize Winners. Just another way of dumbing down the Nobel prize.

By: sean egan

sean egan — Fri, 26 Sep 2008 06:32:30 +0000

What is RegEMed and can we add it to the list of Common Acronyms used on this blog.
Are there any onff island uses/references

By: Hu McCulloch

Hu McCulloch — Fri, 26 Sep 2008 03:46:33 +0000

Stan #3 quotes the Providence (RI) Journal to the effect,

Michael E. Mann, a Nobel Prize-winning scientist, had just spent an hour explaining why he thinks there is virtual scientific consensus that people are causing the earth to warm and sea levels to rise, when a self-described “left-leaning, pro-environment person,” a meteorologist, rose to angrily dispute him.

Umm, Al Gore won a Nobel Peace Prize for passing Mann’s HS off as Lonnie Thompson’s Ice Core data. But that’s not quite equivalent to Mann having won a Nobel Prize himself. Or did I miss something?

By: stan

stan — Fri, 26 Sep 2008 01:42:02 +0000

I suppose you have seen this, but just wanted to pass it on in case you haven’t. http://www.projo.com/news/content/URI_Honors_Colloquium_25_09-25-08_LUBN73R_v12.1607f3c.html

Mann doesn’t seem to like you.

By: Hu McCulloch

Hu McCulloch — Thu, 25 Sep 2008 20:51:43 +0000

The pick-two effect should be present at both high and low frequencies. The apparent difference may just be due to the size of the histogram bins, relative to the spread of the correlations. The high-frequence correlations have a higher sample size, and hence a tighter distribution. If the high freq. bins were made proportionately smaller, they might show similar bimodality, especially for the TR graph.

By: Steve McIntyre

Steve McIntyre — Thu, 25 Sep 2008 18:32:57 +0000

A further example on this. Yule 1926 calculated correlations between sine series sampled more frequently than their period, but with random displacement one to another. The correlation distribution was strongly bimodal as shown below. (This is the famous paper on spurious regression with the example relating C of E marriages to mortality - one which has remarkable RE statistics (so I guess it must be a validated relationship [Wahl and Ammann 2007].