Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!linus!decvax!microsoft!uw-beaver!cornell!vax135!ariel!hou5f!hou5e!hou5d!hogpc!houxm!ihnp4!we13!burl!duke!unc!tim From: tim@unc.UUCP Newsgroups: net.misc Subject: Re: Re: The Earth-Centered Universe Message-ID: <5589@unc.UUCP> Date: Wed, 20-Jul-83 15:31:39 EDT Article-I.D.: unc.5589 Posted: Wed Jul 20 15:31:39 1983 Date-Received: Fri, 22-Jul-83 13:12:42 EDT References: gatech.307 Lines: 53 The phenomenon sometimes called "psi-missing" in psi research is usually pointed out as one of the things that is obviously wrong with the methods in the field. I do not like psi research, I do not believe in psychic powers, but I also dislike smug unfairness on the part of scientists. Here's what I learned in statistics a few years ago: a fundamental part of the evaluation of experimental observations (in psychology, at least) is the null hypothesis. The null hypothesis, in a nutshell, is that the observations made can be attributed to chance; that is, that there is no significance to the observations. You then see to what extent your observations contradict the null hypothesis. Using a variety of mostly mathematical means, beyond the scope of this discussion, you arrive at a measure of how probable it is that the null hypothesis is correct. If there is a low probability (5 to 10 percent is a common threshold) that the observations were due to chance, then you say that the results are significant. If someone were to guess no cards right out of a five-card deck in one thousand trials, the results exceed any reasonable threshold of significance. The null hypothesis is strongly contradicted. This is not in itself what you would call "evidence of psychic powers", but it is, from the definition of significance, a significant result. If you can see no other way of explaining it except to assume that there is some hidden force transmitting some sort of information, that's something you'll just have to live with. To the best of my knowledge, there is no well-documented case of psi-missing being significant in the overall scope of an experiment. This article is an attempt to remove some of the unfairness that scientists reserve for their most despised opponents. Not only scientists do this, of course; the Amazing Randi, a stage magician who enjoys provably debunking fraudulent psychics, wrote an excellent book on Uri Geller (a former stage magician who seems to have decided there was more money in refusing to admit that there was illusion involved), but in this book he ridiculed the idea of psi-missing, proving a deep bias and a lack of comprehension of the scientific method. Scientists should know better than this, and that's why I get irked when they abandon their scientific ideals in the presence of people they disagree with strongly. The feeling seems to be that there is no need to even give a fair hearing to certain beliefs. Recently, I have been asked to justify my keeping an open mind on astrology. Given the lack of evidence against astrology, I am asked to justify keeping an open mind? If I believed in it, this might be a reasonable objection, but since when is keeping an open mind in the absence of evidence a sin? ______________________________________ The overworked keyboard of Tim Maroney duke!unc!tim (USENET) tim.unc@udel-relay (ARPA) The University of North Carolina at Chapel Hill