posted 04-08-2006 07:41 PM
I was recently asked by an attorney from the Center for Court Innovation in New York, during a training conference with the Allie Foundation (Allie was murdered by a repeat, known, sex offender), from MA, to discuss in two sentences or two minutes (as if I could do that) what it swrong with CVSA...In my view, their are two things wrong with it.
First, what the hell is a microtremor, and why can't we find that in the physiology, psychology, or psychophysiology literature?
Second, there is not one single physiological response or reaction phenomena that is uniquely associated with anything! Diagnosticity is achieved through statistical correlations that are useable, though imperfect. They are imperfect because all human physiological response or reaction phenomena are associated with multiple stimuli. Diagnostic (statistically predictive) accuracy results only from the aggregated correlational efficiency that results from combining multiple associated, but distinct reaction phenomena that occur in response to a predictable stimulus.
I heard Skip Webb a few years ago, respond to Leonard Saxe at the APA conference (maybe 2002?) with a beautiful example about fever, elevated white blood cell count, and pain on the lower right abdomen (each of which can result from multiple causes), when combined, their correleational efficiency (even indepedent of predictive statistics) would signal to 9 out of 10 doctors that a patient has an appendicitis, and 9 out of 10 times they would probably be correct. (These are not Skip Webb's words, but his point was well made.)
Simply put, CVSA attempts to diagnose deception or truthfulness from a single physiological reaction feature, and one that is very difficult to succsinctly define or understand.
r
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"Gentlemen, you can't fight in here, this is the war room."
--(Dr. Strangelove, 1964)
Polygraph Place Bulletin Board
posted 04-08-2006 06:09 PM
