lane99 wrote on Jan 24
th, 2005 at 8:57pm:
Don't you think the context of the quote from page 214 (which I had read prior to your post) is there is a practical difficulty to obtain evidence regarding efficacy/non-efficacy because in real-life situations there are many variables which are difficult to quantify and control.
The plethora of uncontrolled (and, indeed, uncontrollable) potentially confounding variables that beset CQT polygraphy certainly complicate any attempt to determine a meaningful accuracy rate for the procedure. (So, too, does CQT polygraphy's lack of standardization.) But the quoted passage from the NAS report does not offer such difficulties as an explanation for the virtual absence of any evidence on the
incremental validity of polygraph "testing." This is an area in which research could be done, but (for reasons that are not too hard to guess) hasn't. For example, a study could be designed comparing the accuracy of decisions made by interrogators using a polygraph versus those made by 1) interrogators without a polygraph, or 2) interrogators using a non-functional polygraph strictly as an interrogational prop.
Quote:However, the opinion is given that the polygraph indeed can ascertain truth from lie at much greater than chance under the right conditions.
But it is virtually impossible to know whether "the right conditions" exist with regard to any particular polygraph examination administered to any particular person on any particular day.
Quote:Thus it seems to me this website is exaggerating when they equate polygraphs with astrology or tarot cards (I'm assuming that those two practises can NOT perform at a level much greater than chance).
That which is stated on the AntiPolygraph.org home page is: "The simplistic methodology used in polygraph testing has no grounding in the scientific method: it is no more scientific than astrology or tarot cards." This statement is concerned with scientific underpinnings, not potential accuracy "under the right conditions." CQT polygraphy has no scientific basis as it lacks both standardization and control (regarding which, see Dr. Drew C. Richardson's
remarks to the NAS polygraph review committee) and is not supported by any theory that explains known facts. It is in this sense that the comparison with astrology and tarot card reading is made.
While a polygrapher might, under the "right" conditions (again, we can't truly know whether such conditions have been met), "discriminate lying from truth telling at rates well above chance, though well below perfection," so, too, might an interrogator who is
not using a polygraph. Again, there is no evidence that the former makes determinations that are more accurate than the latter.