Testing the girl with X-ray eyes

Natasha Demkina, the girl with the X-ray eyes, Is finally being exposed ("Testing Natasha," May/June 2005). There are always those in the population who claim extraordinary powers, but scientists who are in tune with what is real and what is not real come forth and expose them for the charlatans that they are.

I can see how she can grab dues or may know the client's condition beforehand, being prepped to perform in front of her believing spectators. How funny that she can see through clothing but can't see through a common fabric screen.

Natasha, unfortunately, is young, and I hope the criticism doesn't effect her negatively, but enough is enough.

Joseph Anthony Soyo

Walnut Creek, California

Can a test be too fair? That would appear to be the case in the testing of the supposed X-ray eyes of Natasha Demkina.

Fairness in testing is essential, but given that no sane or honest person would contend that anyone has X-ray eyes, why not design a test that would put more of the onus on Demkina, who claims such powers, to prove it?

Granted, the testers did not have a lot of time to design the test and arrange the many details needed to accommodate it, but I think it would have been much more interesting to have conducted a simpler test.

That she and her team got to the test site early and observed the arrival of some of the "scannees" is no surprise. Given the sneakiness of charlatans of her ilk, the "scannees" should have already been in place. Then, she should have been delivered to an unknown (to her and her team) testing location.

As well, Demkina should have been put in front of each of the seven subjects and asked to describe what she saw inside them with her supposed X-ray eyes. Of course, each of the "scannees" would have had something for her to describe that could be detected by X-ray. Also, her translator or her mother or anyone else who had an interest in proving her phony powers should have been separated from her by a screen. After such a test, then her guesses (because that is what they would be) could have been compared to X-rays of the "scannees." Under the conditions of such a test, I don't see how she could have come up with anything close to four out of seven hits.

As it is, I have the uneasy feeling that SKEPTICAL INQUIRER has unwittingly delivered ammunition to the enemy. Supporters of Demkina will look at the results of the testing and say, "Hey! She got four out of seven!" and trumpet the fact that she did better than chance even under the adverse conditions of being tested by an unsympathetic bunch of skeptics. And you can be darn sure that anyone who would believe that someone has X-ray eyes isn't going to read SKEPTICAL INQUIRER's article on the details of her testing, that explains how it was actually done. Too bad--opportunity missed.

B. Abbott

Port Coquitlam,

British Columbia

Canada

Ray Hyman's article, "Testing Natasha," notes that it was agreed upon prior to testing that five correct matches would be the minimum acceptable score that would convince the authors "of a possible ability to diagnose subjects with sufficient reliability to be useful." Readers might be interested to know that the following probabilities are computed (through use of the matching distribution) for obtaining 0, 1, 2, 3, 4, 5, and 7 matches: 0 matches--.368; 1 match--.368; 2 matches--.180; 3 matches--.0624; 4 matches--.0139; 5 matches--.004; 7 matches--.0002. (It is not possible to have six matches without having a seventh.) Although a skeptic myself, and not one who would be inclined to use Natasha's services even if she could produce at least five matches, I believe that, in all fairness, Hyman should have noted that the likelihood of obtaining four correct matches is, in fact, quite low--the value .0139 achieving statistical significance at the 0.5 level (and barely short of the .01 level).

Even given the fact that (as Hyman notes) elements of control in the study may have been compromised, possibly providing Natasha with sensory cues, it would seem to me that a reasonable argument could be made for further investigating the girl's abilities.

David Sheskin

Professor of Psychology

Western Connecticut State University

Danbury, Connecticut

Ray Hyman and Andrew Skolnick conclude that Natasha Demkina's performance in their test of her ability to see inside patients' bodies warrants no further investigation, because she correctly matched only four, not five, of seven subjects to their ailments. However, statistically, Natasha performed remarkably well. A random guesser would do as well or better less than 2 percent of the time. (There are 5,040 possible orderings of cards, seventy orderings with exactly four correct, twenty-one with exactly five correct, and one with all seven correct; exactly six correct is impossible.)

Apparently, Natasha was not just guessing, and the effect was relatively large. So, why conclude that no further testing is warranted? Her claim to paranormal powers is, of course, incredible, but the post hoc arguments explaining away her score are equally unconvincing.