…since the Hockeystick has been already very thoroughly discredited

but in #135,

You say they “confirm[...] the basic temperature shape going back to the 1500s”, but that’s not in dispute.

you’re saying the hockey stick is okay between 1500 to present. Thats almost the entire range (1400-present) reported by Mann, Bradley & Hughes 1998. This is also the region over which many other proxy studies agree pretty well. This is roughly half of the entire time range of Mann, Bradley & Hughes 1999, Mann and Jones 2003. The span between 1000 and 1500 is the uncertain range, which even the NRC and NAS have concluded.

That the more remote half of the plot, with much less coverage by independent studies, is more uncertain is NOT “thoroughly discredited”, not by any stretch.

If a temperature reconstruction by MacIntyre & McKitrick (linked above in #134) is a strawman, they seem to have set it up themselves, by presenting a graph comparing Mann et. al. 1998 with one labeled “corrected version” which shows early 1400s temperatures over twice as high as those around 1950. That spike is not the MWP – the MWP typically appears between 900 and 1100 AD in certain reconstructions. And, by the way, it appears to be limited to parts of the northern hemisphere. For example, the Ljungvist data you link to above is compiled from locations, half of which are north of 60N latitude and 2/3 of which are north of 40N!

Paul replied:”TP, warming is fastest where ever the activists pump their millions and millions in advertising seeking monetary rewards.”

There are easily found maps on the internet. Advertising does not affect thermometer readings. For example:
http://en.wikipedia.org/wiki/File:GISS_temperature_2000-09_lrg.png

Paul further said:” Science has nothing to do with CAGW. Follow the money. ”

I did – research grants were spent on scientists, graduate students, supplies, instruments.
Temperature measurements are done by thousands daily, as a hobby.

Contrarians don’t actually do research, but PR directed at those unable to judge the merits of their arguments – see Dunning-Kruger effect.

Regarding the fraud question, I would remind you that I nearly got banned from this place for trying to discuss the evidence of that. I’m not going to comment on it again without clearance from the moderators.

For what it’s worth, I don’t think it’s a useful thing to do from the point of view of the science. We already know all we need to. But this isn’t a new development. AG’s (on both sides) have been doing this sort of thing for decades. Politics has always been a dirty game.

You mention the NAS examining the result. Here’s some of the evidence given to the Barton Committee by the head of that study.

CHAIRMAN BARTON. I understand that. It looks like my time is expired, so I want to ask one more question. Dr. North, do you dispute the conclusions or the methodology of Dr. Wegman’s report?
DR. NORTH. No, we don’t. We don’t disagree with their criticism. In fact, pretty much the same thing is said in our report. But again, just because the claims are made, doesn’t mean they are false.
CHAIRMAN BARTON. I understand that you can have the right conclusion and that it not be–
DR. NORTH. It happens all the time in science.
CHAIRMAN BARTON. Yes, and not be substantiated by what you purport to be the facts but have we established–we know that Dr. Wegman has said that Dr. Mann’s methodology is incorrect. Do you agree with that? I mean, it doesn’t mean Dr. Mann’s conclusions are wrong, but we can stipulate now that we have–and if you want to ask your statistician expert from North Carolina that Dr. Mann’s methodology cannot be documented and cannot be verified by independent review.
DR. NORTH. Do you mind if he speaks?
CHAIRMAN BARTON. Yes, if he would like to come to the microphone.
MR. BLOOMFIELD. Thank you. Yes, Peter Bloomfield. Our committee reviewed the methodology used by Dr. Mann and his coworkers and we felt that some of the choices they made were inappropriate. We had much the same misgivings about his work that was documented at much greater length by Dr. Wegman.

You say they “confirm[...] the basic temperature shape going back to the 1500s”, but that’s not in dispute. We know about the LIA. Sceptics may argue about how accurately we can measure it, and may be dubious about the magnitude, but the widespread view is that there has indeed been warming over the past few centuries.

It was actually a very clever remark on the part of the NAS, politically. It conceded the entire game to the sceptics, but was worded in such a way that it looked like support for the consensus.

Regarding testable claims, McIntyre and McKittrick make no claims that their data and methods are capable of reconstructing temperature. (And indeed, have suggested they are sceptical that it is even possible.) This has been a common strawman, regarding “their” reconstruction. None of their work is intended to be a reconstruction, only a demonstration that the MBH 99 reconstruction is not robust.

If you want to know if alternative results are possible, take a look at Loehle’s or Ljungqvist’s reconstructions. (You might have to plot it yourself, I’m afraid.) I don’t endorse this one, either. But it’s a part of a considerable body of evidence that supports the MWP.

I don’t check every statement made by McIntyre, Wegman, etc., but I have checked a considerable number of them, and if anybody gives me a half-way plausible reason to doubt something they say, I will try to check it out. I know my own biases. For what it’s worth, you (amongst others) have been very helpful to me, making me chase up things that I hadn’t previously considered sufficiently, which helps me learn the subject in greater depth. You guys force me to keep thinking about it. And there are many sceptics that I have little time for, like Miskolczi, because I’ve checked them out and found them to be wrong. I do take my nom de plume seriously.

Now: back to your comment #8, that folks are circling the wagons around Mann, for the purpose of defense of the assertions of global warming.

There is much insinuation that Mann committed scientific fraud, but I have yet to see any evidence that he did so. That’s why the phrases “fishing expedition” and “witch hunt” are apt descriptions of what Cuccinelli is doing. That makes Cuccinelli a bully, in a position of power, who is abusing it for political purposes, singling out one scientist, looking for anything that might be used to drum something that can be used to attempt to discredit him. Mann is an innocent victim, and if he can assaulted like this, so can any scientist or academic for their work.

I can’t speak for anybody else, but that makes me angry. At this point, it doesn’t matter if he’s picking on Mann or any other scientist or academic, nor does it matter what they published or claimed. At this point, its not even about global warming any more. An attorney general is charged with very serious responsibilities to the public (see http://en.wikipedia.org/wiki/Attorney_General_of_Virginia) and is thus given a great deal of power. Cuccinelli is abusing that power in a way that cannot be allowed to stand. This is a clear violation of our legal, justice and government systems and runs counter to the American way of life.

The issue of climate change HAS become political, but it is members of the right who have made it so, and now Cuccinelli has jumped in, trying to take the lead on that side. Shame on him and those who cheer him on. Cuccinelli and his supporters have now taken on the mantle of the religious authorities who fought against the Enlightenment and the officers of political correctness in communist China and the Soviet Union who suppressed whole bodies of science in those countries in the last century.

…since the Hockeystick has been already very thoroughly discredited.

thoroughly?! THOROUGHLY?! As far as I can tell, works repeatedly presented to contradict Mann et.al. appear to originate from only two groups (small ones at that) McIntyre et. al. and Wegman et. al. On the other side, basically supporting Mann (albeit with criticisms) we have for starters, the National Research Council, the National Academy of Sciences, and various scientific professional organizations. Before you jump in with objections of “Appeal to Authority” and “Argumentum ad hominem” I add that the NRC and NAS members consider the great deal of independent work confirming the basic temperature shape going back to the 1500s as well as the claims of the detractors. If McIntyre et. al. and Wegman et. al. are right where the National Academy of Sciences is wrong, they have a steep hill to climb in regards to burden of proof, because the evidence is piling up in favor of a recent steep temperature rise w.r.t the last several centuries. By jumping into the fray, McIntyre and Wegman and company are now valid targets or subjects of the same kind of withering scrutiny which Mann has been subjected to.

For example, aside from a lot of criticism of Mann’s statistical methods, McIntyre and McKitrickdo actually make a testable claim, that using their data and their methods, they get a large temperature rise at 1400 (fig 8). Is there any independent supporting evidence for this?

Nullis in Verba, I look at your nom de plume, and wonder if you are as skeptical of the claims McIntyre, Wegman etc as you are of man climate researchers, or if you simply take their work at face value.

Nice work Paul. You managed to show a lot of places that are warming faster than the average rate for either the hemispheric or global average. Only one of them claims to be the fastest rate of warming anywhere, which naturally only one can (at least until it’s dethroned by a later measurement). Assuming the rate of warming at all sites is normally distributed, fully half of the world should be warming faster than the global average (aka the rest of the world). You think your list of places warming faster than the average proves exactly what?

Mike G, It was not my intention to leave you out in my #128 response. When possible and addressed directly in a civilly I make an attempt to reply. As you only used “Paul” you slipped past me initially. Of course I recognize the absurdity of the fact that fully one half of all believers in the faith of Catastrophic Anthropogenic Global Warming fall below the IQ average of the Congregation of CAGW believers.

You however have failed to acknowledge the absurdity and futility that I pointed out in my post regarding the propensity of alarmist headlines and the lack of fruit that they yield. Preaching to the choir isn’t suppose to work like that is it? Thousand upon thousands of shock and awe headlines and articles misrepresenting the observations and data of scientific studies(but too often not the contrary politically correct antithesis of the data/observation conclusions) which have yielded only one out of every three democrats in the United States to the church of Catastrophic Anthropogenic Global Warming with two our of three democrats recognizing that Catastrophic Anthropogenic Global Warming is overblown and of little concern. Headlines, shouting, drum circles and mindless activist protest do not make up for the lack of science. The mental masturbation and hubris of today’s “Climate Science” is fine for academia and should be encouraged however, CAGW/Climate Science should never have been thought of as being out of short pants in the world of science.

It is remarkable that CAGW has been as influential as it has been so far. However with the 100s of millions spent by “Big Green” on lobby efforts in the USA this goes to show how much GREEN goes into government policy today. Are you pissed at the Obama administrating for pointing out that the Global Warming Industry spent 100s of millions recently and were not able to swing a single vote in the United States senate?

Catastrophic Anthropogenic Global Warming as it exists today is not about science. It is about GREEN money. Government money, tax payer money. The solar PV units on your neighbor’s roof or the wind turbines on your neighbor’s property are only profitable & possible because you and your other neighbors pay for them through your taxes and increases on your electric bills. This is only going to work(if you can call it that) for a limited time. Arrests have already been made regarding the Global Warming Industry around the world. Big GREEN money bigs big thugs.

Catastrophic Anthropogenic Global Warming and the Global Warming Industry utilizes politics and the cigar smoke filled back rooms to steal public funds. The day(s) of reckoning is coming. CAGW is being yanked from the buddy-review journal pages and brought into the world of hard science and reality.

Statements of could, might and likely made by activist scientists will not stand in a United States court of law. With China not only building but actually putting on line one or two low technology “dirty” coal fired power plants every week true believers of Catastrophic Anthropogenic Global Warming are only deluding themselves. Nobody believes your tales of woe but the feigned angry who have out stretched hands for EU & US money and the bureaucracy that see the possibility of the creation of a world energy arbitrator and tax authority as stated in the failed Copenhagen accord.

These BA blog global warming threads reflect the fringes of reality. The leftist democratic party has two out of every 3 members recognizing that Catastrophic Anthropogenic Global Warming is of little concern. Where does that put you on the political spectrum?

Catastrophic Anthropogenic Global Warming will be handled in court. No amount of belly aching will stop it.

All is not lost Mike, there will be other causes for kids and malcontents to follow blindly to replace Catastrophic Anthropogenic Global Warming when all is said and done.

The controversial bit of the hockeystick is not the blade, it’s the flat handle, that “got rid of” the MWP.

See : http://www.youtube.com/watch?v=vrKfz8NjEzU&p=029130BFDC78FA33

which deals neatly and entertainingly with the Medieval Warm Period which turns out to be a regional rather than global phenomenon. Climatology has developed and learnt more since that was first studied.

It also looks at Mann’s hockey stick graph and the controversy over it .. Notably, it wasn’t just based on tree rings but also used historical data, coral samples, ice cores and other data.

Also, its more than just the work of Michael Mann as many other individual climatologists have also done similar studies replicating similar results from different sets of data – as it concludes there :

“There isn’t just a hockey stick anymore but a whole hockey team.”

Then too looking further back over the Earth’s history we *do* find carbon dioxide levels were much higher in the very distant past .. and the results weren’t healthy! Indeed, they caused mass extinctions as seen here :

http://www.youtube.com/watch?v=uE6at2IEUOU&p=029130BFDC78FA33

As for the old “Mars is warming” canard expressed in headline excerpt by (#83.) Paul in Sweden here :

Global warming hits Mars too: study

Global warming could be heating Mars four times faster than Earth due to a mutually reinforcing interplay of wind-swept dust and changes in reflected heat from the Sun, according to a study released Wednesday.

This clip :

http://www.youtube.com/watch?v=BSXgiml5UwM&feature=player_embedded

put’s that notion to rest with excellent planetary graphics to boot & is my fave out of that whole series – so thanks for giving me an excuse to mention & link it again.

There are plenty more where these came from – and plenty of other sources that back up what this is saying too.

OK, one more time. There are three distinct claims: it’s an invalid argument, it’s conclusion is false, it’s fraudulent.

The first means that the argument does not imply the conclusion, but that does not mean the conclusion is false. The second means that the conclusion is false too. The third means that it was published knowing that it was an invalid argument.

CAGW-believers often get confused over this. If I say the argument is invalid, they assume that implies the conclusion is false and respond with other confirmations of the same result and the “the errors don’t matter” argument. The discussion splits 20 different ways as you then have to dig out the flaws in each and every other study, and the discussion loses focus. So I was saying that pointing out flaws does not imply the conclusion is correct, and so cannot logically be dismissed with alternative demonstrations that it is.

Having said this, CAGW-believers immediately leap to the conclusion that I’m saying that the argument may be flawed but the conclusion is correct. I’m not, but I haven’t provided any arguments for or against that.

Fraud is a different question. There is some evidence to say so, but I suspect a lawyer could wriggle out of it fairly easily, and it’s not somewhere I particularly want to go.

As for whether Cuccinelli is right to investigate – from a “finding things out” point of view I think it’s a waste of time, since the Hockeystick has been already very thoroughly discredited. Justice for that will come eventually – I’m not in any hurry. From a political point of view, there are possibilities. Whether you agree would therefore depend on your politics.

#124,

Yes, of course I’ve looked at Mann08. The basic method behind all the studies is to use methods that emphasise Hockeystick shapes, and then sneak a Hockeystick shape into the input roster. Some people use Bristlecones, some use Yamal, some use the older version of Polar Urals, in Mann08 Mann used upside-down Tiljander, which is not a tree ring series (it’s a mud core from a lake) but otherwise is similarly flawed. As published by Tiljander, it shows a mild rise in the Medieval warm period, but dropped dramatically in the 20th century because it was corrupted by run-off from ditch digging. Mann’s algorithm matched the 20th century corrupted data to the temperature record, and turned it upside-down. The warm medieval period becomes a cold one, and drags the average down.

This is why we try to avoid playing the game. Dozens of flawed studies are put in play, and if you take the time to pick apart any one of them (a task made more difficult by the refusal to share data and methods) then “the errors don’t matter” because of all the other studies, and it’s kept. Stop using the MBH99 Hockeystick, and then we’ll talk about the others.

If you think MBH98/99 were sufficient, see if you can find where in those papers they discuss their choice of short-centered PCA and the details of the stepped reconstruction.

RE is only standard in climate science. As far as the rest of the statistical community goes, R2 and CE are better known. R2 has its shortcomings, as do all methods, but this is why statisticians recommend doing multiple tests and requiring them all to pass. A failure with R2 is a clear sign of trouble.

#126,

The standard ‘AGW-sceptic’ position is that there have been an alternating series of warm and cold periods. The Minoan warm period, the Roman warm period, the medieval warm period, the little ice age, and the modern warm period. Over the past 400 years, we have emerged from the LIA and the temperature has gone up. It’s not controversial. It’s not what we mean by a ‘hockeystick’ shape.

The controversial bit of the hockeystick is not the blade, it’s the flat handle, that “got rid of” the MWP.

I’ve actually seen people present 400 year graphs with rising temperatures and described them as “confirmation” of the hockeystick. You’re making the same confusion.

The problem is that McIntyre has demonstrated that Mann’s algorithm was producing hockey sticks when fed with random data.

You actually *believe* that could be possible? Words cannot express how much stoopid there is in that statement. This is the level of gullibility that so-called ‘skeptics’ sign up to.

Days of Unicorns and Pixie Dust are over. Academic freedom is great and should be encouraged but when you build a bridge, a building, a pharmaceutical, or contribute to government policy you have to go into the realm of reality that the rest of the world operates.

MBH98, MBH99, Bristlecone pines, short centering and principal component analysis will be subject to true and open analysis in a United States court room. Maybe the Virginia AG will get there first maybe the hoard waiting for the United States Environmental Protection Agency(EPA) to finally get their feet wet and attempt to put in place ridiculous restrictions on the US energy economy will get there first. The MBH, climategate, HADCRUT & NASA GISS temp records are all but a few dominoes that will fall.

Where is the ARGO data?

Why are meetings on transparency held behind closed doors?

When discovery proceedings begin for the court cases against the US government regarding CAGW, start the doomsday clock for the religion of Catastrophic Anthropogenic Global Warming.

With 2 out of every three “Democrats” recognizing that CAGW is over stated, think what is going to happen to tales of woe predicted 100 years out without any actual evidence is going to play out in a United States Court room?

Hey if Cali goes ahead with AB 32 and turns down the California Jobs initiative in November there might be no need for even a court case. When California lays off teachers, when Universities have to cut back on services(even the Republic of Berkley), when California businesses move even faster to Arizona & New Mexico, state furloughs go 2 weeks a month across the board people on the Left Coast are going to wake up.

OMG, it might happen even faster if the “Mass Wind” Ted Kennedy Wind Farm is actually installed offshore and the leftists in MA see their first electric bills.

Reality takes time to settle in with some but there is no escaping it. Sweden is doing great. We purchase discount wind power on the spot market from Denmark. Denmark of course subsidizes the Danish wind market and Danish citizens pay some of the highest if not the highest electric rates in all of Europe. Sweden sells Denmark our Nuke and Hydro power at a premium and we have just built the highest number of phrenology clinics or the largest windfarm in the world for the UK that the Swedish national power company is going to rake in billions.

The activists here at the BA blog are all too willing to delude themselves. Wake up and smell the roses. The radical left does not own science. Science is science. This will all play out in time. Hey, if CAGW does turn out to be true I am going to be really pissed at the activist scientists that were involved because they never produced evidence or reproducible studies that could be evaluated outside of their buddy system.

Time will tell in the mean time look for some really great court cases.
Paul

You and I have a basic disconnect. My understanding is that the flaws in MBH98, when corrected, did not significantly change the shape of the curve. I take that to mean that the original work was substantially correct — which is what the NRC panel said. I’m not aware of anyone trying to claim the paper was flawless.

And when independent groups repeat the work and get similar results, that is what I understand to be confirmation according to the scientific method. So I really don’t see what justifies this incessant rehashing of the defects in the MBH98 paper.

Sorry, it won’t wash. You say that MBH98 reaches a bogus conclusion, then immediately turn around and say its conclusion that the twentieth century was warmest “is not news, and not controversial.”

If you intentionally include Bristlecones and the Gaspe cedar series, even though you know they aren’t temperature proxies, you can get Hockeysticks. Or are you saying that Bristlecones are a “good” choice?

Did you even look at Mann 08? That did the analysis without relying on tree ring data at all and it didn’t significantly change the results.

The distinctiong being…?

The distinction being he explained the methods in the results. McIntyre acted like it was some big revelation that Mann had done this, but he explained what he did and he explained why. It is easy enough to verify whether the reasons are valid, but McIntyre just threw them back in.

The information required to replicate the result is not in the paper. There is a general overall description, but essential details are omitted.

Which specific details are those?

Did you actually check they fixed the problems reported in Wegman?

I’ve read the analysis that includes the fixes. Have you?

I’m told the team have subsequently withdrawn that conclusion. The admission was found buried away in a blog thread in a comment by Gavin.

So they do withdraw results that are incorrect. This refutes your entire argument that they refuse to withdraw results when they are shown to be flawed

It was an analogy. Statistics can be done incorrectly, and getting a correct answer by incorrect mathematics (that isn’t even an approximation) is just as wrong as cancelling digits. I understand it well enough.

It is a horribly flawed analogy. You still have not provided any reason to think that the mathematics are incorrect.

I was referring to the RE threshold, and the failure of the R2 verification. Getting an r-squared of 0.00003 between your reconstruction and the instrumental data and claiming it passed the test is ridiculous.

As best as I can tell looking at the literature, RE threshold is a pretty standard approach in climate science due to known limitations on the R^2. It was apparently even in textbooks on the subject even before Mann 98.

Likewise, when trendless red noise gives hockeysticks, something’s wrong.

I already addressed this, in a comment you replied to no less.

Just to clarify, you’re claiming that Mann, et. al. were not just being sloppy, they were outright wrong?

Yes.

Seems to say “yes they were outright wrong” but the following

I’m just saying that just because I’m saying flaws in the Hockeystick don’t imply that the conclusion is incorrect, that isn’t an admission on my part that it’s correct.

seems to say that the were not necessarily wrong, which are two different things.

The reason I press this point is that there seems to be a widely held view that Mann committed scientific fraud and that Cuccinelli is doing the right thing to investigate. My question is: what is the precisely is the act of fraud? Doing analysis incorrectly (if that were even true) doesn’t even begin to qualify for such a strong charge.

If you intentionally include Bristlecones and the Gaspe cedar series, even though you know they aren’t temperature proxies, you can get Hockeysticks. Or are you saying that Bristlecones are a “good” choice?

“I don’t have to take Mann’s word for it, he published it in a paper.”

The distinctiong being…?

“It’s right there in the paper! What more do you want?”

The information required to replicate the result is not in the paper. There is a general overall description, but essential details are omitted.

“Did you actually check whether they made a difference?”

Did you actually check they fixed the problems reported in Wegman?

“You mean the same paper that said this:”

Yes, that one. I looked at the data.

“This conclusion can be extended back to at least the past 1,700 years if tree-ring data are used, but with the additional strong caveats noted. “

I’m told the team have subsequently withdrawn that conclusion. The admission was found buried away in a blog thread in a comment by Gavin.

“I already addressed this. You simply don’t understand statistics. Statistics is not the same as arithmetic.”

It was an analogy. Statistics can be done incorrectly, and getting a correct answer by incorrect mathematics (that isn’t even an approximation) is just as wrong as cancelling digits. I understand it well enough.

“Which specific statistic are you referring to? McIntyre posted a lot of different statistical critiques, all of which that I have seen have been debunked.”

I was referring to the RE threshold, and the failure of the R2 verification. Getting an r-squared of 0.00003 between your reconstruction and the instrumental data and claiming it passed the test is ridiculous.

“And I notice you completely skip over my criticism of your description of statistics.”

I assume you mean “Using sub-optimal data sets and/or statistics will not necessarily render your results totally invalid. It may mean that the results are just slightly off from the real values.”

I agree. It may. But if you use data sets that are known not to be temperature proxies, process them with a method that is now known to over-emphasise a particular outcome, such that the non-proxies end up being weighted tens to hundreds of times greater than the rest of the data, we can have no confidence that the results are even close.

Some of those trees were subsequently resampled, and it was found you could get two completely different results in different cores from the same tree! One wiggled around doing nothing special, and the other shot up 6 sigmas in a massive ramp at the end. It’s proposed that it’s because they’re strip-bark trees – the bark stripped off one side causes the other side to grow faster to compensate. Tree rings are often elliptical or irregular or distorted – it’s a well-known problem in dendrology. (Next time you visit Mann’s homepage, take a close look at the rings in that log he’s leaning on.) Whatever the explanation might be, a tree that gives two completely different results simultaneously is not responding to temperature. So when it constitutes by far the biggest contribution to your temperature reconstruction, something is obviously wrong.

Likewise, when trendless red noise gives hockeysticks, something’s wrong. When the verification R2 falls to 0.00003, something’s wrong. When you’ve included precipitation series, and mislocated and mislabelled them, and done peculiar extrapolations to fill in data and transpositions between columns, and used out-of-date data, and nobody noticed, something’s wrong. This isn’t just a little bit wrong, it’s massively wrong.

But I’m giving it up at this point. You can continue to believe it’s been validated if you like. But I’m telling you, trying to defend it just encourages and propagates scepticism from anybody willing to examine the details with an open mind. This is why Cuccinelli is doing it – because he knows he can rely on you to continue to defend the indefensible.

If you make slightly different choices about the inputs, you can get reconstructions of different shapes, and this was just one example. There are plenty of others.

Yes, it’s possible to intentionally make bad choices that radically change the results. That is McIntyre’s approach.

And I would note in passing that just because Mann has said something doesn’t necessarily make it so. To always take Mann’s word as gospel and dismiss McIntyre’s as dishonest is begging the question.

I don’t have to take Mann’s word for it, he published it in a paper. All I had to do was read the paper.

As Mann well knows, the reason they were “reduced” to searching the ftp site is that Mann refused to tell them what they needed to know to replicate the reconstruction.
When they asked for clarification of the method and confirmation that they had the right data and interpretation before publishing, he wouldn’t reply.

It’s right there in the paper! What more do you want?

There are several examples where the authors claimed to have fixed the problems but actually didn’t.

Did you actually check whether they made a difference?

Or simply introduced entirely new problems, like upside-down Tiljander in Mann08.

You mean the data that didn’t make a difference whether it was included or not?

There are several examples where many of the problems were fixed, and a different result was obtained.

You mean valid fixes? I’ve seen to many “fixes” that were totally bogus.

The most recent being Ljungqvist 2010.

You mean the same paper that said this:

Our temperature reconstruction agrees well with the reconstructions by Moberg et al. (2005) and Mann et al. (2008) with regard to the amplitude of the variability as well as the timing of warm and cold periods, except for the period c.ad300-800, despite significant differences in both data coverage and methodology.

That is a period, I should add, the Mann 2008 expressed a lack of confidence in, so it is hardly surprising that they ended up being revised. From Mann 2008:

This conclusion can be extended back to at least the past 1,700 years if tree-ring data are used, but with the additional strong caveats noted. … The reconstructions appear increasingly more sensitive to method and data quality and quantity before A.D. 1600 and, particularly, before approximately A.D. 1000.

– end Mann 08 quote

But as I said before, this is missing the point. An incorrect method that only gets the ‘right’ answer by coincidence is unacceptable. If somebody calculates the fraction 95/19 by cancelling the 9’s on top and bottom to get 5/1, that’s invalid arithmetic. If you did that in elementary school, you’d get it marked wrong.

I already addressed this. You simply don’t understand statistics. Statistics is not the same as arithmetic.

Moreover, it just gives people like Cuccinelli the opportunity to batter you with it repeatedly. The excuse that “the errors don’t matter” is illogical and unscientific and doesn’t convince anyone, so keeping on using it just turns more and more people sceptical.

If flaws actually invalidate the results of a study, then they are usually abandoned. I see it all the time. However, abandoning the results of a study simply because of baseless pressure by the anti-science crowd is, in my opinion, a great way to convince them to step up their attacks. It tells them that simply yelling loudly enough, whether that yelling has any validity or not, is enough to get us to abandon papers they don’t like. I think it is better to take a stand, to make it clear that bullying will not make us abandon good science.

Mann used a novel and poorly understood statistic instead of the normal ones, and thus calculated the threshold wrongly, as McIntyre/McKittrick subsequently showed. I actually posted the verification statistics above for the Hockeystick (from Wahl & Amman 07), and Mann’s reconstruction failed. What’s more, it’s almost certain that he had already calculated them and knew it.

Which specific statistic are you referring to? McIntyre posted a lot of different statistical critiques, all of which that I have seen have been debunked. I may have missed one, but you will need to be more specific.

And I notice you completely skip over my criticism of your description of statistics.

Yes. Although what I’ve said here doesn’t cover that, and it’s a long and complicated diversion, so I’m not going to try to assert it. I’m just saying that just because I’m saying flaws in the Hockeystick don’t imply that the conclusion is incorrect, that isn’t an admission on my part that it’s correct. It’s a different discussion.

#112,

None of that is disputed, and none of that contradicts anything that I said about it. If you make slightly different choices about the inputs, you can get reconstructions of different shapes, and this was just one example. There are plenty of others.

And I would note in passing that just because Mann has said something doesn’t necessarily make it so. To always take Mann’s word as gospel and dismiss McIntyre’s as dishonest is begging the question. As Mann well knows, the reason they were “reduced” to searching the ftp site is that Mann refused to tell them what they needed to know to replicate the reconstruction. When they asked for clarification of the method and confirmation that they had the right data and interpretation before publishing, he wouldn’t reply.

#113,

There are several examples where the authors claimed to have fixed the problems but actually didn’t. (Or simply introduced entirely new problems, like upside-down Tiljander in Mann08.) There are several examples where many of the problems were fixed, and a different result was obtained. The most recent being Ljungqvist 2010. Note that just because I cite it doesn’t mean I believe it – I simply note that multiple interpretations are possible.

But as I said before, this is missing the point. An incorrect method that only gets the ‘right’ answer by coincidence is unacceptable. If somebody calculates the fraction 95/19 by cancelling the 9′s on top and bottom to get 5/1, that’s invalid arithmetic. If you did that in elementary school, you’d get it marked wrong.

You not only need to be able to calculate the right answer, you need to know that it is the right answer. If you want to rely on other studies reaching the same conclusion, then fine. Drop MBH98 and rely on those other studies. But keeping MBH98 just because you like the conclusion, or for sentimental value, even though you know it’s full of holes is just silly.

Moreover, it just gives people like Cuccinelli the opportunity to batter you with it repeatedly. The excuse that “the errors don’t matter” is illogical and unscientific and doesn’t convince anyone, so keeping on using it just turns more and more people sceptical.

#117,
Mann used a novel and poorly understood statistic instead of the normal ones, and thus calculated the threshold wrongly, as McIntyre/McKittrick subsequently showed. I actually posted the verification statistics above for the Hockeystick (from Wahl & Amman 07), and Mann’s reconstruction failed. What’s more, it’s almost certain that he had already calculated them and knew it.

Short version: it is not sufficient to simply show the plots are similar-looking, since if you try enough time it is possible to fit anything with random data the way McIntyre and McKitrick did. That is why we have specific statistical tests to determine whether the results of such an analysis are different than what you would expect from purely random inputs.

Mann had already done those tests when McIntyre and McKitrick posted that criticsm, and they passed. When you apply those same tests to McIntyre and McKitrick’s random data, the tests fail.

In other words, Mann had already checked to make sure McIntyre and McKitrick’s criticisms were false before they even made them, and the results of those tests were published in his paper.

That is why I requested earlier for something from someone with the slightest bit of integrity. McIntyre and McKitrick have none whatsoever.

Here is a link to a more detailed explanation:
www. realclimate. org /index.php/archives/2005/01/on-yet-another-false-claim-by-mcintyre-and-mckitrick/

http://www.natutech.nl/00/nt/nl/49/nieuws/2299/index.html

“As I said before, it is not sufficient to show there were flaws in the satistics, you need to show that the flaws actually have a significant impact on the results. If they don’t then the flaws are not relevant.”

The problem is that McIntyre has demonstrated that Mann’s algorithm was producing hockey sticks when fed with random data. Your argument is akin to saying that a calculator which produces result “4″ for every operation is fine, because we are only interested in calculating 2+2, and never 4+3.