Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site randvax.ARPA Path: utzoo!linus!decvax!harpo!seismo!hao!hplabs!sdcrdcf!randvax!edhall From: edhall@randvax.ARPA (Ed Hall) Newsgroups: net.audio Subject: Re: Results of a subjective speaker wire evaluation Message-ID: <1691@randvax.ARPA> Date: Sat, 18-Feb-84 00:20:33 EST Article-I.D.: randvax.1691 Posted: Sat Feb 18 00:20:33 1984 Date-Received: Wed, 15-Feb-84 06:13:54 EST References: <824@drufl.UUCP> Organization: Rand Corp., Santa Monica Lines: 37 ---------------------------- That's not a double-blind test! It's hardly even a `single blind' test. In a double-blind test: 1) The order in which the cables were listened to would be random. This can include listening to the same cable twice in succession. 2) Neither the person running the test nor the subject would have any way (other than by listening) of determining which cable was in use. (This is the double-blind part, and has proven important in evaluative studies of all kinds, since unconcious cuing (e.g. the `Clever Hans' effect) is a definite posibility.) 3) The results would be checked for statistical signifigance. This is tough for a small sample. Admittedly, #2 is a tough order. It possibly could be done by placing short, coded wire pigtails on each end of several samples of cable, and somehow hiding which cable a given pigtail attached to. Or, cable- changing could be done behind some sort of screen (not exactly double- blind, but so long as no one in the listening room knew the sequence to be used it should suffice). I'm not denying that there can be a difference made by speaker cables. But if you claim a study is `double-blind', you'd best know what you are talking about. -Ed Hall decvax!randvax!edhall P.S. `Clever Hans' was a horse around the turn of the century who seemingly could answer all sorts of yes/no and small-number questions by stamping his hoof. It was eventually noticed that Hans could only answer questions his owner knew the answer to, and then only when the owner was within eyeshot. It seems that the horse was cued by his owner's posture and breathing.