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Comment Re:What precentage caused by man? (Score 1) 324

Why? Mainly because it most clearly demonstrates the issue.

It's not clear to me, especially in light of the faux pas about CRU, just what issue that is. My intervention, as you will see if you refer to my original post, as well as pointing out that you had the wrong Man(n) (you had Jones) and taking issue with the hyperbolic attack on the statistical failings, such as they were, of the good Professor: was that the original hockey stick paper has long been superseded.

In any case, it is my (limited) understanding of Mann, Bradley & Hughes 1998, is that it is generally accepted both that better statistical methodology could have been applied; and that the methodology actually used contained identifiable mistakes (however minor they may have been). I believe Dr Mann himself concedes as much. "Really really bad," however, probably tends towards hyperbole.

If he knew what he was doing, then he was actively trying to deceive people, which is far worse.

That's a reading the "hide the decline" [of correlation between tree-ring and other proxy data relating to the sub-set of Russian trees after mid C20th, was that it?] comment might naturally lead someone to form. But really isn't it just the that the blow-tourch of criticism on this particular subject matter renders good-enough methodology not nearly good enough? Scepticism, where it is informed, is a great boon to science.

Comment Re:What precentage caused by man? (Score 1) 324

It's hard to not be an ass towards someone who is willfully ignorant.

Tell me about it!

The only saving grace you can grant Mann here ...

Are you still talking about that 20 year old paper or the present one? And if the 1998 paper, then why? Have I defended that paper in this thread? Beyond foregrounding the fact that the work which has superseded it has "more or less" confirmed the original findings? I merely noted that calling Dr Mann "really really bad at statistics" was "perhaps" to overstate matters. (No really, look back at what I've written).

(Off topic, I did hint at the fact that I don't accept the view science can simply ignore data sources which are subject to difficulties of interpretation, which seems a form of the nirvana fallacy). But it being not strictly germane, and this being an old discussion, I'll decline any invitation to go down that line of argument here. Which nicely segues ...

The only time, I trust, that I am ever willfully ignorant, is in my refusal to "hear" statements clearly irrelevant to the point under discussion ... a perverse outcome of my legal training, you will understand.

The intention of my anecdote, OTOH, was to ask that you try to be sensitive to the fact that those of us already suffering the putative effects on weather of changes to our climate are likely to find an overzealous adherence to the heterodoxy on this topic to be ... hmm ... unusually my vocabulary fails me.

Comment Re:What precentage caused by man? (Score 1) 324

In other words, they weren't able to establish that their measurements were proxies for temperatures.

Don't be disingenuous. They were not able to make, as you quoted, any "statistically robust" reading based on the both the parcity of data and the fact that the C20th is too shorter a period to make any meaningful statement under their methodology. You know this because, once again, it lies adjacent to the cherry-picked verbiage you misquoted:

Our global paleotemperature reconstruction includes a so-called “uptick” in temperatures during the 20th-century. However, in the paper we make the point that this particular feature is of shorter duration than the inherent smoothing in our statistical averaging procedure, and that it is based on only a few available paleo-reconstructions of the type we used.


What is sad, is someone is so wedded to untruth that they find it necessary to hide the substantive portion of a quote they muster.

Comment Re:What precentage caused by man? (Score 1) 324

"...and therefore is not the basis of any of our conclusions. Our primary conclusions are based on a comparison of the longer term paleotemperature changes from our reconstruction with the well-documented temperature changes that have occurred over the last century, as documented by the instrumental record."

Comment Re:What precentage caused by man? (Score 1) 324

[Y]ou don't realize weather is not climate.

Don't be an ass mate. The unprecedented weather events we are witnessing with improbably regularity are likely the outcome to changes in climate.

Using tree rings to reconstruct historical temperature was demonstrably a mistake at the time, because they don't match thermometers. Mann knew that at the time

That does not go to the assertion that he was "really really bad at statistics." Which is not to say I accept that statement (from memory, and I'm not minded to go to the effort and check, the problem was with a particular sub-sample of tree-ring data).

Comment Re:What precentage caused by man? (Score 4, Insightful) 324

I've been modded down already

Well it wasn't one of your more accurate contributions was it? Oooops.

Beside the confusion between Penn State and the University of East Anglia, to say Dr Mann is "really really bad at statistics" is perhaps to overstate the actual criticism leveled at his now infamous 1998 paper. In any case subsequent reconstructions, --and the last word, I presume, goes to Marcott et al. 2013 --more or less confirm the original conclusions of Mann et al.. I'm would assume you (and I genuinely respect your intelligence and erudition phantom) are already aware of that.

it's also worth mentioning that this paper is using computer models

And, invaluable though they may be, we would certainly exercise caution when considering the findings of simulations. In any case, we would naturally be sceptical of any only recently published paper. It's the weight of the extant literature of course, including the examination and perhaps replication by the entire profession of newly published work, that forms the best available science.

I realise that the plural of anecdote is not data, and I realise that warming here in Australia is occurring at a faster rate than globally, but this summer just gone has been truly alarming. Driving my family through 46C heat on the NSW South Coast in Feb was the first time I was literally scared of the temperature (not just uncomfortable but frightened that the vehicle and air-con might give out).

Comment How often do you reinvent the wheel? (Score 5, Informative) 324

why isn't there more recent material published showing the proven change?

For the same reason physics journals are not filled with recent papers investigating whether falling objects move towards or away from Earth. The human contribution (established not only by the C12/C13 ratios but also by estimates of rates of fossil fuel consumption) is no longer a matter of serious dispute. The argument has moved on to issues of climate sensitivity; just what the actual effect will be on tropical storm formation &c. If you want to see the original work establishing the human fingerprint you would need to look at papers from last century, when this was still a live issue. You are better off going to the most recent IPCC summation of the science (which will link you through to original papers), which in this case would be Chapter 8 and Chapter 10 of the 2015 WG1 report of AR5.

In the meantime that link provided gives a very nice concise summary of one of the lines of evidence by which the human fingerprint was established.

I would think that ...

... you would have thanked OP for that informative link. Or were you not the AC who wanted to know how we know about the anthropogenic contribution to observed warming?

Comment Re: Victim Blaming? (Score 1) 113

So what do you propose instead? Keep in mind that blaming the accused (before evidence or judgement is given) is basically as wrong as blaming the accuser. How do you express skepticism or withhold judgement in a way you see as correct?

As you say it's "basically as wrong" to go one way or the other. I already answered this above, but to recap: What I propose is nothing more radical than adhering to the ordinary presumptions a court is required to make, for example, in a criminal process. That is to say that a) the accused is entitled to the (rebuttable) presumption of innocence and b) the accuser(s) (and indeed all witnesses) are entitled to the (rebuttable) presumption of honest testimony. As I wrote above, the process can be thought of as a resolution of the contradiction thus set up.

If there is relevant evidence tending to speak to a client's guilt, one seeks to exclude it on the basis that it is unlawfully obtained; hearsay; tendency or coincidence evidence; &c. Bearing in mind the restrictions due to the credibility rule, one seeks to impugn the reliability or character of the witness; to show the testimony is self-serving; &c. And of course, where possible, to show that the evidence led is demonstrably false. However, the mere fact that evidence that tends to show the guilt of an accused is not a reason to presume that evidence is false (and then have to prove, beyond reasonable doubt, its veracity). The point of the presumption of innocence, after all, is that the state lead evidence to rebut it.

Now as private citizens reaching mere opinions, we need not, of course, be anywhere near as punctilious as a court, much less need we work to a criminal standard of proof (my opinions are held on the 'balance of probabilities'). However bearing in mind the proper presumptions as we consider the limited evidence available should stop us jumping to hasty conclusions either than an accused is guilty or an accuser a liar.

What's the right thing to say when one of your friends states that either the accuser or the accused has done Horrible Things?

How about: "You know I really envy your confidence in coming to quick conclusions with very little direct evidence." ;) Being the contrary bastard that I am, I often begin arguing the opposite of any position put to me. TBH, I'm a bit self-centred, probably you'd get on better with people if you just go along with the tribal prejudices of your friends.

Comment Re: Victim Blaming? (Score 1) 113

A soft answer turneth away wrath: but grievous words stir up anger. --Prov 15:1

It's amazing how judgemental you can be when you phrase it kindly :)

Yes, I was left with an uneasy feeling that this might be going on here .. but as I said above, I withdraw. Looking at the totality of your contributions I find nothing to persuade me from the presumption ;) that you have anything but the best intentions in mind.

Your basic point, if I understand you, is the all too common to rush to blame the victim, even where blame is clothed in the mantle of "scepticism," (e.g. "I'm not saying you're lying, but I won't believe you until you prove you are not lying") is a wrong and we should guard against expressing our doubt in that way. It would certainly be intolerable where the accusations are well founded (which we cannot know until the evidence is examined), and as against OP assertion that "[v}ictim blaming happens far less than false claims," one rather suspects the exact opposite to be the case.

Comment Re: Victim Blaming? (Score 1) 113

If you lead with sympathy, you're good. If you lead with accusations, then you're bad.

A problem, I think, is that too many people assume the presumption of innocence we must extend to an accused, involves a corollary presumption of guilt against the veracity of the accuser. That is not so. Someone making a complaint is entitled to the rebuttable presumption that their accusation is made in good faith, just as the person against whom the complaint is raised is entitled to a presumption of innocence.

The "process" --and this clearly applies to a curial process, but arguably it ought also apply to an investigative one --might be understood as a process of resolving the contradiction, by reference to the available evidence, between the two presumptions reason (or law) requires us to make.

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