FIGURE 5-1 Sensitivity and false positive rates in 52 laboratory datasets on polygraph validity.

NOTES: Points connected by lines come from the same dataset. The two curves are symmetrical receiver operating characteristic (ROC) curves with accuracy index (A) values of 0.81 and 0.91.

involving naïve examinees untrained in countermeasures: for such examinees and test contexts, the polygraph has an accuracy greater than chance. Random variation and biases in study design are highly implausible explanations for these results, and no formal integrative hypothesis test seems necessary to demonstrate this point.

Second, with few exceptions, the points fall well below the upper left-hand corner of the figure indicative of perfect accuracy. No formal hypothesis test is needed or appropriate to demonstrate that errors are not infrequent in polygraph testing.



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement