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Re: Telepathy/Parapsychology etc.

 Stewart Robert Hinsley wrote [of the dubious nature of meta-analysis]:
 > If one does enough experiments one will eventually get one with a result
 > a few standard deviations ought. Combining this with the rarity of the
 > publication of null results gives rise to a bias.
 > For example, consider a system in which there is no correlation between
 > a postulated cause and effect. Say 100 experiments are done, of which 80
 > give a null result, 10 give a borderline positive correlation, and 10
 > a borderline negative correlation.  [and so on, a crisp, clear exposition of the problems inherent in meta-analyses wrongly or stupidly used]
 All this is clearly true, and would be piercingly salient if that were the 
 way parapsychologists dealt with their data these days, and if that were the 
 kind of selected data sets they had available to them.  Alas, all the 
 skeptical rejoinders on this thread have had an eerie quality of arm-chair 
 pontificating.  Is nobody interested enough to fire up the web sites I cited 
 and check for themselves the arguments and data deployed by skeptic Ray Hyman 
 and pro-psi statistician Jessica Utts?
 I ask this, at the risk of being heavy-handed and boring, because that old 
 red herring about *discarded null result data sets* has been exhaustively 
 studied in parapsychology, and informed skeptics such as Hyman tend to agree 
 that it's not a big problem.  (They point to lots of *other* possible 
 problems, often fatal in their estimation.)
 The `file-drawer' question, as it's known, implies (for a well-known Ganzfeld 
 meta-analysis) that parapsychologist Charles Honorton's 42 studies - of which 
 55 percent showed `hitting' - would need to be balanced by some 440-580 dud 
 experiments that are not known to anyone in the field.  Such studies are 
 extremely time-consuming, and the number of labs conducting Ganzfeld research 
 is small.  It is an absurd conjecture.  Besides, for more than a decade the 
 policy among parapsychology journals has been to report *all* results, null 
 and otherwise, precisely to obviate this suspicion.  If you're crazy enough 
 to take up career parapsychology, you at least know that you earn as many 
 brownie points for a well-conducted null experiment as for one corroborating 
 a psi hypothesis.
 I invite skeptics to take a close look at the papers by Hyman and Utts, then 
 come back and tear into the *real* targets...
 Damien Broderick