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« Gas prices | Main | A correspondence of warmists »
Thursday
Jul072011

More bend it by Bayes

Nic Lewis's article on the IPCC's "bending by Bayes" of the Foster and Gregory estimate of climate sensitivity got quite a lot of interest a few days back. Nic has followed up with a searching letter to IPCC lead author Gabriele Hegerl.

I think this one will run for a while yet.

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Reader Comments (72)

Surely it's "Bend it like Bayes", in honour of Beckham, Bish. But absolutely brilliant name. Your time in the sick bay has not been wasted.

Jul 8, 2011 at 12:22 AM | Unregistered CommenterRichard Drake

What about honoring Mann'e mentor and recent author of his own Hockey Stick story - bend it like Bradley.

Jul 8, 2011 at 1:40 AM | Unregistered CommenterSteve McIntyre

That actually made me snigger out loud Steve McIntyre. Who said the sly old fox doesn't have a sense of humour? ;)

Jul 8, 2011 at 2:15 AM | Unregistered CommenterLC

Yes this will be important in scientific circles. All those "gate" nonsenses culled from Greenpeace are only in the politicians/dumbed down IPCC reports. The latest scandal is in the "scientific" IPCC paers - and is not trivial.

Jul 8, 2011 at 2:25 AM | Unregistered CommenterBill

Gabriele Hegerl who has an office 3 doors along from Geoffrey Boulton in Edinburgh, right? Looks like they're going to need another inquiry...I wonder whether the perennially limber Boulton will oblige?

Jul 8, 2011 at 4:32 AM | Unregistered CommenterZT

ZT, are you suggesting: bend it like Boulton.

Jul 8, 2011 at 5:01 AM | Unregistered CommenterSteve McIntyre

Yes, doesn't the phrase capture an air of ethical flexibility and preening pomposity worthy of the UEA's professional troubleshooter?

Jul 8, 2011 at 6:16 AM | Unregistered CommenterZT

Steve McIntyre wrote:

What about honoring Mann's mentor [...]

Steve, as a fellow Canadian writing on a British blog, I am shocked and appalled to see that your writing has been so adversely influenced by those damn Yanks! The word is "honouring" is it not? ;-)

But "bend it like Bradley" and "bend it like Boulton" are both so apt ... and brilliant!

Which makes me wonder ... Perhaps it's time to reconsider the expansion of the acronym "IPCC". May I humbly suggest: "International Purveyors of Contrivances & Codswallop".

Jul 8, 2011 at 6:18 AM | Unregistered Commenterhro001

ZT, are you suggesting: bend it like Boulton.

No for inquiries (and the odd Parliament building or 2) its

Spend it like Muir

Jul 8, 2011 at 7:15 AM | Unregistered CommenterBreath of Fresh Air

On a more serious note ... I could be wrong (it has been known to happen!), but while I readily confess to being statistically-challenged, my impression from the many comments in response to Nic's original post is that no one has suggested that his conclusions are in doubt. Yes, there have been comments from IPCC defenders, but their "arguments" have been more in the line of deflection than correction.

What is somewhat surprising (to me, at least) is that there have been so few responses to Nic's letter to Hegerl - particularly from the usual footsoldiers in the virtual army of <Curry detractors>.

All of the above suggests to me that Steig taught O'Donnell et al a valuable lesson: forget about having post-publication conversations behind closed screens.

My hat's off to Nic not only for that which I do not comprehend (through no fault of his), but also for his perspicacity in bringing the "conversation" into the open.

And my hat's also off to Judith Curry for giving the floor - on a much watched platform - to Nic's revelations, questions and expositions.

Jul 8, 2011 at 7:28 AM | Unregistered Commenterhro001

@hr001

Intentional Peddlers of Contrived (Climate) Crap?

Jul 8, 2011 at 7:28 AM | Unregistered CommenterLatimer Alder

Chaps

I thought it a bit unkind on Rev Bayes to suggest that he was guilty of bending things! Hence "bend it by Bayes".

Jul 8, 2011 at 8:00 AM | Registered CommenterBishop Hill

@Latimer Alder

Yeah, that might work, too. Except for your (parenthetical) which suggests that your ... uh ... acronymic reconstruction might be slightly modified and more (you should pardon the expression) robustly applied to UNFCCC: Uniilateral Notions of Contrived Climate Crap.

Jul 8, 2011 at 8:04 AM | Unregistered Commenterhro001

I rather expect, in the light of this scandal, that Pachauri will close down the IPCC stating that AR5 will be the last publication and then come back some few weeks later with some new publishing enterprise - perhaps with 'Sun' in its title.
:)

Jul 8, 2011 at 8:20 AM | Unregistered Commentersimpleseekeraftertruth

ooops ...

UNFCCC: Uniilateral Notions of Contrived Climate Crap.

should be:

UNFCCC: Uniilateral Notions Forcing Contrived Climate Crap

Jul 8, 2011 at 8:23 AM | Unregistered Commenterhro001

@simpleseekeraftertruth

I rather expect, in the light of this scandal, that Pachauri will close down the IPCC stating that AR5 will be the last publication and then come back some few weeks later with some new publishing enterprise - perhaps with 'Sun' in its title.

As in "Sun enchanted heating"?!

OK, I'll get my coat!

Jul 8, 2011 at 8:50 AM | Unregistered Commenterhro001

You lot are on form this morning :)

may I suggest: IPCC: Intellectual Propaganda Contrivance Club

Jul 8, 2011 at 9:14 AM | Unregistered CommenterFrosty

I never imagined so much wonderful humour could be stimulated by such miserable behaviour from the IPCC and I dips me lid, as a wide-eyed Kiwi innocent abroad, at such a consort of individuals brilliantly bending metaphor!

Jul 8, 2011 at 9:17 AM | Unregistered CommenterAlexander K

Either the IPCC WG1 authors had little expertise and knowledge in statistics in that they cocked up in representing the current state of the science, or they had enough expertise and knowledge to change scientific results that fitted the 'consensus'.

Maintaining scientific integrity and dodgy IPCC authoring seem to be mutually exclusive ethical and professional actions for this current crop of climate scientists.


Either way the usual suspects look suspiciously bad.

Jul 8, 2011 at 9:20 AM | Unregistered CommenterMac

If Nic's letter to Gabriel Hegerl, featured on Judy Curry's blog, is a fair sample of his output, I am more than a little in awe of his abilities, his exemplary good manners and his patience. The comments following this letter are illuminating in that the cast of characters that usually climb on to anything that has even a faint whiff of adverse criticism of the IPCC are staying very quiet.
On a slightly different note, this thread has impelled me to 'hit the books' in attempt to get my head around the Rev. Bayes' seminal ideas and the development of theories examining probability. My ignorance is huge but repairable.
And it's nice to see that the Bishop has made a return to health.

Jul 8, 2011 at 10:19 AM | Unregistered CommenterAlexander K

The Bishop is right to protect the Reverend Bayes from calumny! His methodology is rigorous, but is open to abuse by those who select prior distributions not based on their knowledge but based on a desired outcome.

Will we see a dramatic reining-in of the IPCC’s arrogance and aggression this time round? They must know that more and more specialists are sitting like coiled springs waiting to shred any nonsense from spin-merchants and other prior-conclusion-driven participants, be they scientists or political radicals or both.

These people became carried away with their exuberance over having found computer modellers and computer models capable of producing results so well-suited to:

(1) promoting radical agendas for, variously, the dismantling of industrial societies, the promotion of ‘world government’, the development of an elite ruling class based around control of ‘the environment’, creating generations of children raised as ‘little political activists’, and no doubt many others pursued by those able to spot a golden opportunity
(2) producing newspaper headlines to scare people (and create countless secondary and tertiary levels of more innocent and well-intentioned activists intent on ‘doing their bit for the planet’)
(3) funding research grants for work on and around these models by the core ‘team’ – the few dozen at the very heart of the technical side of CO2 alarmism
(4) funding research grants for work by perhaps tens of thousands of scientists, sociologists, geographers, and no doubt others, on the impacts of climate variation (given the variability of this climate, all of this work could be focused on just about any era if one could imagine ways of getting data for them – there is nothing, after all, particularly unusual or untoward about weather etc in recent decades that couldn’t be found in earlier ones)

In parallel with the exposure of this technical manoeuvre to bring observational data in line with model outputs, Donna Laframboise has been revisiting a more blatant manoeuvre – that of running a press conference to make assertions in line with alarmist worldviews but in blatant disregard of available expertise and data. A disregard which observational data since has served to further expose as foolish in the extreme. I refer to the Trenberth/McCarthy press conference on hurricanes and global warming in 2004. More here: http://nofrakkingconsensus.com/2011/07/05/landsea-the-ipcc-the-union-of-concerned-scientists/ and here: http://nofrakkingconsensus.com/2011/07/07/chris-landsea-and-the-moral-midgets/

Donna refers to moral midgets getting a Nobel Peace prize. We shall gain more insight into the morality of the IPCC by its response, or lack of response, to this recent work by Nic Lewis.

Meanwhile, may the good Reverend rest easy. (more on him here: http://bayesian.org/bayes)

Jul 8, 2011 at 10:35 AM | Unregistered CommenterJohn Shade

Alexander K @ 9:17 AM,

'at such a consort of individuals brilliantly bending metaphor!'

As the Lebowsky might say,

A metaphor with 'like' is, like, a simile, man (Mann)?

:)

Jul 8, 2011 at 10:43 AM | Unregistered CommenterChuckles

"Sun enchanted heating"

Comedy gold hro001

Jul 8, 2011 at 10:53 AM | Unregistered Commentermct

As an example to others, I hereby retract my suggestion of Bend it like Bayes, with humblest apologies for any offence caused to Bayes, Beckham or Bishop. Bend it like Boulton, on the other hand, is apt, given the collegiality with Hegerl. Indeed, if climate bendiness is an onion (stay with me), we have here an example from the inner ring - estimation of climate sensitivity being as central for the IPCC as it gets - and the outer (yet another Climategate inquiry bent into submission). A metaphor to make the eyes water.

Jul 8, 2011 at 10:54 AM | Unregistered CommenterRichard Drake

John Shade:
“... specialists are sitting like coiled springs waiting...”
Quick! Josh! a drawing!
(sorry John. Just winding you up)

Jul 8, 2011 at 10:57 AM | Unregistered Commentergeoffchambers

Chuckles,
My tutor in Eng.Lit 101, more than a day or three ago, defined wit as 'the ability to bend a metaphor' - I do know what a simile is!

Jul 8, 2011 at 12:02 PM | Unregistered CommenterAlexander K

I guess it is hard to sit like a coiled spring, and hard to believe that coiled springs do any waiting. And I don't know if I have mangled a simile or a metaphor. It was all clear prior to 10:57 AM (thanks geoff!) but my posterior view is muddled.

Jul 8, 2011 at 12:30 PM | Unregistered CommenterJohn Shade

Breaking News: In order to improve its reputation, the IPPC has just bought rights from News International to allow its next report to be called "The News of the World".

Jul 8, 2011 at 12:33 PM | Unregistered CommenterFrederick Bloggsworth

Well, we need to keep ourselves amused while those crickets chirp and we await responses from the IPCC. So:

IPCC: Institute for the Political Co-option of Climate
Theme song: Some Enchanted Evening, I Will Fool a Stranger
Now hiring: former News of the World staff

Jul 8, 2011 at 12:51 PM | Unregistered CommenterJohn Shade

John Shade,

Are hacking skills required or relevent?

Jul 8, 2011 at 1:30 PM | Unregistered Commentergolf charley

<Zed mode>

Stop posting about that, all of you. You're a disgrace.

Post about this instead. Befehl ist Befehl.

</Zed mode>

Jul 8, 2011 at 1:35 PM | Unregistered CommenterJustice4Rinka

@ Mac

Either the IPCC WG1 authors had little expertise and knowledge in statistics in that they cocked up in representing the current state of the science, or they had enough expertise and knowledge to change scientific results that fitted the 'consensus'.

My surmise would be the former. Statistics is tricky and advanced mathematics. It is one of those areas where there are three levels of ability.

1/ that of a Cambridge mathematics graduate
2/ that of someone who's done enough maths to know this stuff is hard
3/ people so stupid they don't realise this is hard, don't know their easily-obtained answer was easy to obtain because it is in fact wrong, and therefore mistake themselves for people competent to use statistics when anyone in 2/ or 1/ could tell them they're not.

Nick, who's a 1, has just informed the IPCC (and by implication climate psyence in general) they're a 3.

They can't be expected to enjoy it.

Jul 8, 2011 at 1:41 PM | Unregistered CommenterJustice4Rinka

Blind it like Oxburgh?

Jul 8, 2011 at 1:57 PM | Unregistered Commentergolf charley

@J4R

I disagree. I think this shows the IPCC as a 1 or better on your scale. You have to be very skilled indeed to cloak your adjustments under the guise of a "uninformed prior".

Admittedly, it is an uninformed prior on a function of the relevant variable...which makes it a strong prior on the relevant variable...but that just makes it all the more impressive!

-J

Jul 8, 2011 at 2:08 PM | Unregistered CommenterJames

Blend it like MikeMann?

-J

Jul 8, 2011 at 2:10 PM | Unregistered CommenterJames

Q. How many IPCC Scientists does it take to change an awkward Bayesian climate sensitivity graph?

A. Only one or two, and they don't have to have prior knowledge.

I'll get my coat.

Jul 8, 2011 at 2:12 PM | Unregistered Commenterlapogus

Justice4Rinka, your analysis may explain the lack of comment from Foster, Gregory, and Hegerl to Nic's assessment.

It could well be that they (like me) have very little idea what he's on about. Perhaps they are also frantically reading stats text books to try and catch up (in this case, like Alexander K, but unlike me).

Jul 8, 2011 at 2:16 PM | Unregistered Commentersteveta_uk

STRAIGHTEN it like Michael Mann ...

Jul 8, 2011 at 2:18 PM | Unregistered CommenterGeary

Just a reminder from the verbal evidence of Lord Oxburgh to the House of Commons Committee for Science and Technology, 29 November 2010,
Q28 “Pamela Nash: The report suggests that the key task of the CRU was to analyse the data sets of others. However the CRU scientists did not have the level of statistical skill to do this. Do you think that the CRU scientists are people of integrity but out of their depth when it comes to statistical analysis? Lord Oxburgh: You are quite right…”

Jul 8, 2011 at 2:27 PM | Unregistered Commenteroldtimer

So the Press Complaints Commission is to be scrapped and Cameron wants an enquiry into how the the PCC, Police and News International failed to find the truth in three separate investigations.

No similarities at all with climatology then

Jul 8, 2011 at 2:33 PM | Unregistered Commentergolf charley

Bayesian statistics have no role to play in science. Bayesian statistics are wonderful for discovering one's weaknesses as a gambler. They are helpful for making decisions under uncertainty. They give game theorists another publication. Yet Bayesian reasoning is based on subjective probabilities. The point is that the good name of science should not be sullied with Bayesian reasoning. The word 'evidence' should not be used with Bayesian statistics without the qualifier "subjective evidence" or "evidence for changes in my subjective beliefs."

I can see now where the IPCC gets the idea that there is a consensus of scientists. When a scientist submits a paper, the IPCC people either find that it supports their case and publish it or they find that it can be made to support their case by choosing the right Bayesian "prior" or, finally, they find that it cannot be made to support their case so they reject it. It is that Bayesian step that gives rise to the idea of consensus.

If I am willing to allow IPCC to select a Bayesian "prior" for my work then I am part of the consensus! IPCC just made me part of the consensus. Consensus about what? Well, about my subjective beliefs. This nonsense should not be dignified with the name of science or the word 'evidence'.

Jul 8, 2011 at 5:11 PM | Unregistered CommenterTheo Goodwin

Theo, I do wish you'd tell us how you really feel.

Jul 8, 2011 at 5:23 PM | Unregistered CommenterRichard Drake

Richard Drake writes:

"Theo, I do wish you'd tell us how you really feel."

Excuse me, Richard. I pride myself on clarity. To paraphrase Lt. Col Kilgore: "Science does not do subjectivity!!!!"

Game Theory does subjectivity. If the IPCC drops the words 'science' and 'scientist' from all their publications then I will be perfectly happy. The IPCC can call themselves Game Theorists. Then the public and decision makers will be better informed. Why would the IPCC complain about that?

Jul 8, 2011 at 6:29 PM | Unregistered CommenterTheo Goodwin

I agree with hro001's comment [Jul 8, 2011 at 7:28 AM]

The footsoldiers have been quiet and the IPCC defenders both few and unwilling to do more than attempt meaningless deflections. I wrote after Nic's first post that they were 'tween the rock and hard place.

At this point, the details of Nic's argument with the handling of the sensitivity study have almost become secondary. EVERYONE has become aware that the IPCC's work on an absolutely critical element of the science is a function of some really weak statistical assumptions. Even if the staunchest IPCC defender (e.g. Martha at Judy Curry's digs) wants to argue that the IPCC handling was scientifically perfect, it cannot be denied that the evidence and statistical underpinning are the opposite of robust. Talk about weakness exposed.

Or as some of my less academically-inclined basketball teammates were want to say after blocking a shot --

"Don't be bringing any more of that weak s@#$ in here!"

It's a new game.

Jul 8, 2011 at 7:07 PM | Unregistered Commenterstan

Stan,

Well said!

The new IPCC disclaimer: "Our very best subjective reasoning yields the conclusion that all levies on taxpayers should be increased ten fold so that we can properly protect your grandchildren from your irrational use of fossil fuels."

Jul 8, 2011 at 7:46 PM | Unregistered CommenterTheo Goodwin

hro001 said,
Jul 8, 2011 at 8:50 AM


“””””As in "Sun enchanted heating"?!””””


= = = = =


Hro0001,


Should that be sung to the tune ‘Some Enchanted Evening’ from the 1949 Rodgers and Hammerstein musical 'South Pacific'?


Your "Sun enchanted heating" could become note #1 on the Climate Skeptics Top Pop Charts!!


John

Jul 8, 2011 at 8:45 PM | Unregistered CommenterJohn Whitman

another sheeps bend

Jul 8, 2011 at 8:47 PM | Unregistered Commenterj ferguson

IPCC = International Pack of Climate Comedians


John

Jul 8, 2011 at 8:58 PM | Unregistered CommenterJohn Whitman

I tend to think the IPCC are a 3, steveta_uk.

Cambridge is the second best university in the world. UEA isn't even the second best university in east Anglia.

If Cambridge says the IPCC are stupid the IPCC should believe them - they accept, indeed insist on, arguments from authority, do they not.

Jul 8, 2011 at 9:23 PM | Unregistered CommenterJustice4Rinka

International Panel on Carbon Comedy?

or

International Panel on Climate Comedy?

Jul 8, 2011 at 9:48 PM | Unregistered CommenterKevYYZ

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