Tuesday, August 14, 2007

Trickster, or failure of imagination?

In his blog, George Hansen expresses concern about a statistical result I published some 14 years ago (1993) in an article on mind-matter interaction (MMI) that. He writes:

... Correlation coefficients were calculated for each of the 16 outcome measures with each of the 33 environmental variables, which resulted in a total of 16 × 33 = 528 correlations. Radin reported that the 16 × 33 matrix produced 44 correlations that were associated with p < .05. He then used the binomial probability distribution to compute the probability of obtaining that many, or (presumably) more, correlations associated with p < .05. He reported a value of p = .0004. I have been unable to reproduce this number ... In any event, Radin’s reported result is statistically significant.

However, the binomial distribution assumes independence for each of the measurements. But the correlations were clearly not independent. For instance, the environmental variables included background X-ray flux and log of background X-ray flux, humidity and precipitation, sunspot number and sunspot number for the day before.... Readers who have some familiarity with statistics may wish to ponder the implications.


The answer to his first concern was due to a simple mistake. I based the calculation on 45 rather than 44 significant correlations. I thank Hansen for spotting this error.

I addressed his second concern in the original article*, as follows:

It might be argued that some of the excess significant correlations in the experimental data might have been due to the fact that some of the environmental variables tested were intercorrelated with each other....



I explored this possibility by, among other things, forming a control correlation matrix using the same environmental variables in their originally recorded order, but randomly scrambling the chronological order of the MMI variables. (Under the null hypothesis, the former and latter variables should not be related in any way.) This control matrix resulted in a nonsignificant number of correlations, supporting the idea that the original matrix contained some meaningful relationships.

Hansen then failed to report that one of the points of this study was to test the idea that one reason MMI is highly variable in laboratory experiments may be due to fluctuations in environmental factors and differences in psychological variables like mood and confidence. Through use of an artificial neural network (Brainmaker, based on a backpropagation design), I demonstrated a genuine relationship between six environmental variables, two psychological variables, and one mind-matter interaction variable. After training the network on half the available data, the correlation between the MMI variable in the other half of the data and the neural network's prediction of the MMI effect was a highly significant r = 0.405.

The conclusions of this study were that (a) the environment appears to modulate MMI performance, (b) there are intriguing hints of space-like and time-like rebounds [in the MMI results], and (c) there is reason to believe that fairly good predictive models of MMI performance are realistically attainable.

To paraphrase Hansen's concern, readers who have some familiarity with his trickster theory may wish to ponder the implications of Hansen failing to report the rest of the story. While I think the trickster concept and lore are interesting, and that Hansen's own book on the trickster is an excellent exposition on that topic, I disagree that psi is forever doomed to a marginal existence.

The reason I don't agree is because similar pessimistic complaints have been voiced throughout history whenever we've been faced with seemingly incomprehensible effects in medicine, physics, astronomy, chemistry, biology, etc. In other words, whenever imagination fails, someone will invariably assert that we'll never be able to understand [fill in the blank], and so they come up with trickster-like theories to allow us to place our ignorance into a mysterious netherworld lying somewhere beyond our understanding. Failures of imagination are common, but promoting theories based on those failures is tantamount to glorifying an anti-scientific position.

* Radin, D. I. (1993). Environmental modulation and statistical equilibrium in mind-matter interaction. Subtle Energies and Energy Medicine, 4 (1), 1-30.

6 comments:

Phronk said...

I've seen this before and I'm sure I'll see it again. It's fascinating how, when one is looking for flaws in an article, they can overlook the fact that the potential flaws were already dealt with. Perhaps "overlook" is too conservative a term, but I hesitate to accuse anyone of intentionally deceiving readers by leaving out important information.

I wonder what you think of Hansen's other mention of your work on his blog. Personally, I think if the biggest flaw in Entangled Minds is an ambiguously worded figure caption, you're doing pretty good. :)

Dean Radin said...

I don't mind constructive criticism. I make no claims for perfection, so I always appreciate it if someone alerts me to a mistake. Such critiques help me to improve my future work. For an example of good criticism, see John Walker's review of Entangled Minds at www.fourmilab.ch/fourmilog/archives/2007-08/000884.html, in which he spots a complete blooper (I wrote the opposite of what I had intended to write regarding the quantum zeno effect). Physicist Daniel Sheehan spotted the same thing in a galley version of EM, but it was too late to fix by then.

What I can do without, what I suspect we can all do very nicely without, are confidentally stupid or mean-spirited criticisms. This doesn't mean that my emotions don't sometimes get in the way, but at least I aspire to provide only constructive, kindly stated feedback.

Phronk said...

Here is some more kindly stated feedback: I agree with John Walker that your explanation of Bell's theorem is the clearest lay-person explanation I have seen. I understood the conclusion before, but never understood why it was true before reading Entangled Minds. Even books devoted to (nonmathematical) physics were not as clear. Thank you for that.

Dean Radin said...

In his blog, George Hansen now offers a new complaint about this same paper, which boils down to the fact that a single Monte Carlo run does not create a distribution from which to estimate chance behavior. This is quite true. If the goal of that paper was to provide a proof-oriented claim, tested against an estimated chance distribution, it would be a valid criticism. But that wasn't the goal, as the paper clearly states.

The point of the paper was to explore the possibility that environmental factors might modulate PK activity so as to make it appear to be weak and erratic. That goal was accomplished. As I stated in one of the conclusions:

"There is reason to believe that fairly good predictive models of MMI performance are realistically attainable. This last point is most important from a pragmatic point of view because it suggests that neural network and other pattern-matching technologies may be of significant value in creating practical applications out of MMI phenomena far in advance of our gaining a clear understanding of how and why MMI works."

This pragmatic focus has been one of my interests for many years. While some people remain stuck solely on the issue of proof, I accept the cumulative proof-oriented evidence that something interesting is going on, and I'm more interested in learning whether PK (or more generally the act of intention) can be used for something pragmatically valuable.

Rick said...

I frankly can't follow what Hansen is talking about in this critical passage:

the binomial distribution assumes independence for each of the measurements. But the correlations were clearly not independent. For instance, the environmental variables included background X-ray flux and log of background X-ray flux, humidity and precipitation, sunspot number and sunspot number for the day before.


I don't know Hansen's training, but I think it can sometimes be counterproductive for (e.g.) an anthropologist to critique an electrical engineering paper, and that a similar mismatch of critique is going on with Hansen's critique of Radin's paper.

Dean Radin said...

The binomial distribution assumes underlying events that are independent of each other. The events in this case were results of statistical tests, and the question he raised was whether those tests were all completely independent of each other. In some cases they were not.

E.g., a correlation between a mind-matter interaction effect and say, sunspots, might give results that are pretty close to a correlation between mind-matter interaction effects and 10 cm solar flux. So the criticism wasn't wrong, it just overlooked the fact that I noted this issue in the paper and that it wasn't central to the whole point of the study.