On 2007-10-15 18:42:41, James Newton wrote:

> Ah, I see the difference Gerhard (and sorry for the miss-spelling as
> well). Thanks for taking the time to explain it to me.

Thanks for reading it, and acknowledging it. I needed that :) -- it seemed
so completely lost in the discussion.

> I do see that as a flaw in the IPCC report, and I should also be clear
> that I don't feel the IPCC is without bias, as Russell and others have
> argued very successfully.

That's the point (for me). Them not adding any hint at their models'
confidence data does seem to be meaningful. Now, if they had added a phrase
like "the confidence levels of the used models are at this point difficult
to assess and therefore we will depart from general scientific practice and
leave any confidence levels out of this report", I think this could have
increased substantially my own confidence. But writing a report like this
without even mentioning once confidence levels (well, they do, in a FAQ,
and that one is not reassuring) seem quite odd and, for me, casts a shadow
of doubt on all the rest. It really looks as if they tried to hide
something, and I wonder what that is, and why hide it.

> I'm glad to hear you can see some agreement with my own position re:
> Erring on the side of caution.

I think that at least between you, Russell and me, there's no disagreement
on this. But for me this doesn't have a lot to do with GW, AGW and the
like; it has much more to do with a generally livable environment. Which is
a different thing for almost everybody, and few if any hard facts enter
that area.

AIUI this discussion was always about the confidence levels in the IPCC's
report. And while I also don't know where Russell took his 90% (or 0.1)
number from, the fact that they don't suggest a wording for a higher
confidence level combined with the fact that they don't give any confidence
levels in their report (until someone actually posts where they give them)
to me sounds like a strong indication that the confidence levels in general
are worse than that. I just don't think they had left them out if they
could have added "with very high confidence" to every result.

Gerhard
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