NCJ Number
193244
Journal
Polygraph Volume: 30 Issue: 4 Dated: 2001 Pages: 228-243
Date Published
2001
Length
16 pages
Annotation
This article examines data from six separate studies to determine evidence of conformity with dependability curves for the Total Chart Minutes Concept.
Abstract
The Total Chart Minutes Concept (TCMC) is a specialized habituation model for polygraph testing. Each of the three traditional channels of polygraph data are more diagnostic at certain periods during polygraph testing than in others, and no two channels have the same exact periods of good and poor productivity. Dependability curves were created to represent the diagnosticity of each of the channels as a function of time. Six sets of data were examined. The data consisted of 7-positon numerical scorings of confirmed field Comparison Question Technique polygraph cases. Scores were summed within channel and chart, then averaged by group, deceptive or nondeceptive. The resulting values were then plotted. The lack of agreement between the various independent field data scoring profiles and the TCMC dependability curves is evidence that the TCMC has little foundation in reality. The TCMC should be viewed with skepticism until supporting data are found. One finding dealt with the question of which polygraph channel really is most diagnostic. Greater separation between average nondeceptive scores and deceptive scores for a channel might signal that that channel was contributing more diagnostic information toward correct conclusions. Another finding dealt with the differences in the pattern of responding between deceptive and nondeceptive examinees. Mounting evidence shows that scoring systems should have cutting scores that are not symmetrical around zero, since the psychophysiological phenomenon is asymmetrical. This data shows that there is a need to adjust scoring methods or decision rules to adapt to the asymmetrical patterns of responding between deceptive and nondeceptive examinees. The data also provide evidence that the electrodermal channel provides more diagnostic information than does either of the other two polygraph channels. 22 figures, 11 references, bibliography