Improving the Reliability of Polygraph Tests.

The report summarizes the work completed during the second year of a two year study to examine the efficacy of using tree-based classifiers to analyze polygraph charts produced in a detection of deception context. Four hundred twenty-six 426 Modified General Question Technique MGQT polygraph charts produced by 144 subjects were used in this phase of the study. Half of the charts were used to develop the tree-based classifiers, the other half were used for cross-validation including estimating the probabilities of misclassification for each of the tree classifiers tested. The lowest misclassification probability achieved was 13.9. Detailed information is provided about research procedures employed to both capture and analyze the data. AN