Sunday, February 5, 2012

Featured on journal Nature blog - response to Chris French and the Shawn Carlson double-blind study of astrology

Yesterday, I was searching for a way to get some mainstream science attention for the criticisms published by various authors and myself of "A double-blind test of astrology" from Shawn Carlson, published in the highly-regarded science journal Nature in 1985. I found that the Nature website has a new guest blog section called "Soapbox Science" and one of the featured short articles is a recent piece named "The rise of anomalistic psychology - and the fall of parapsychology?" by University of London Professor Chris French. Because French mentions astrology and this is the Nature website, I thought it might be a good place to bring up the Carlson issue and I added my comments. All comments are subject to review and at this point I don't know if my comments will make it onto the blog.

Here is the URL:

Here is what I wrote:

Chris, Before you get too cozy with this emerging discipline, it is interesting to reflect on how modern skepticism is transforming itself to become anomalistic psychology. First we have the transformation of CSICOP (Committee for the Scientific Investigation into Claims of the Paranormal) into CSI (Committee for Skeptical Inquiry). CSI dropped the pretense of being scientific in the wake of the Dennis Rawlins "sTarbaby" exposé of the committee's unscientific shenanigans regarding their tests of the Mars effect discovered by the late Michel Gauquelin. (BTW, in 1988, this effect was elevated by Suitbert Ertel through objective data ranking to the status of the Mars eminence effect). This more recent anomalistic psychology approach seems to favor skeptical rhetoric  and lawyering under the guise of "critical thinking" over the scientific evaluation of evidence.

Consider the popular claim that astrology works by cognitive bias. This is a widely held belief among intelligent people, but no one has ever demonstrated it. Although classroom Forer-type tests have been performed hundreds of times, and are widely assumed to disprove astrology, they only demonstrate the Barnum effect, and cannot legitimately claim to refute astrology. The reason is because the sample of "astrology" to be evaluated by the students is carefully cherry picked to maximize the Barnum effect. This is not a scientific test of astrology with proper samples and rating of choices. Nothing of the sort has ever been published. Yet it is always trotted out in discussions against astrology. Is this an example of anomalistic psychology that you teach your students?

It is interesting to find this "soapbox" in the online pages of Nature. Research in astrology is done by interested amateurs, funded from their own pockets, as Gauquelin had done. There has not been a mainstream scientific forum for them to exchange ideas.

For example, In 1985 Nature published an article by Shawn Carlson entitled "A double blind test of astrology.” This article brought instant fame to its author and is still one of the most frequently cited studies to have claimed to scientifically refute astrology. Yet this article was not properly vetted by peer review because it contains design and methodological flaws that should have been caught, if perhaps they were not so well concealed. When evaluated against the actual design of the experiment (which Carlson sets out but does not follow) and the normal evaluations for significance used in the social sciences, the data marginally supports the participating astrologers.

It is frustrating to astrological researchers to see such a prestigious study as Carlson's go unchallenged in mainstream media. For those who wish to pursue the Carlson controversy, and Chris I strongly suggest that you do, please refer to the following links for references to the original article by Carlson and the ensuing peer reviewed discourse by Ertel and myself. My article includes a discussion of follow-up studies. The Carlson study needs a replication that incorporates the many useful suggestions that have been made through the discourse of these and other authors to make a fair and scientific study.

"A double-blind test of astrology":
"Appraisal of Shawn Carlson’s Renowned Astrology Tests":
"Support for astrology from the Carlson double-blind experiment":

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