Monthly Archives: May 2006

More on MBH98 Figure 7

There’s an interesting knock-on effect from the collapse of MBH98 Figure 7 (see here and here). See update from UC in May 2011 below in which he did a “bit-true” replication. We’ve spent a lot of time arguing about RE statistics versus r2 statistics. Now think about this dispute in the context of Figure 7. […]

Spam Karma reset

We’ve had a few new posters fail to negotiate the Spam Karma filter, possibly because of using the same domain for e-mail as spammers use. Also, if you see the comment numbers appear to desynchronize from the quoted comment numbers, its much more likely to be because Steve or myself have restored a comment or […]

MBH98 Figure 7 Unveiled

Sometimes we hear that science is "self-correcting". To be "self-correcting", however, individual people have to step up to the plate now and then and actual do the work. To the extent that the term "science" includes the work of Mann et al., then analysis of MBH98 Figure 7 , which was actually the culmination of […]

MBH98 Figure 7

Since Chefen has brought this figure into play, there’s much to consider about it. [Also see followup here.] For interested parties, the data is at WDCP here . I haven’t got to checking Chefen’s results yet, but wanted to table interesting results in passing. As Jean S noticed, the Corrigendum stated that an “old” version […]

THe Ritson Coefficient

In my previous comment on Ritson’s AR1 calculation, I think that I correctly diagnosed that the calculation was goofy, but I didn’t diagnose what was going on correctly (thanks to Demetris Kousoyannis who emailed me). I’ve re-visited it and I’m pretty sure that I’ve now diagnosed the problem with what Ritson was doing. My starting […]

Something New on MBH98

Just when you think that the MBH98 Little Shop of Horrors has been fully explored, something new turns up. I’ve never spent any time on the last part of MBH98, where he does a "detection and attribution" study linking his temperature reconstruction to solar, volcanic and CO2. All these detection and attribution studies (e.g. Hegerl) […]

Enron’s Climate Change Policy

I’ve posted up a little treat from the past – Enron’s climate change policy as downloaded in October 2002. I knew that Enron was favor of Kyoto before I knew of Michael Mann. In 1998, Enron received the Environmental Protection Agency’s (EPA) Climate Protection Award for its “exemplary efforts and achievements in protecting the global […]

Enron Verdict

A big story today is the guilty verdict on Enron executives Kenneth Lay and Jeffrey Skilling. There are many interesting issues involved in this, but the one that I wish to draw to attention of readers here is that Lay and Skilling were not found guilty of stealing money or looting the treasury, but of […]

AR1 on First Differences

The question for today is how does realclimate go from tree ring series with autocorrelation functions that look like the one in the figure below to a claim that these proxies have an AR1 coefficient of 0.15. We know that they are pranksters, but this looks like a good prank and it is. Autocorrelation Function […]

A Letter to Ritson

Ritson at realclimate did not thank me for helpful discussions on autocorrelation despite lengthy correspondence on my part with him. I thought that the histogram that I posted up earlier today looked familiar. So I looked back at my correspondence with Ritson (who posted up on autocorrelation at realclimate and sure enough, I’d sent the […]