Polygraph Automated Scoring Systems

Reference#: P00440

A polygraph automated scoring system was developed in which polygraph signals are input and a probability of deception is output. To begin the process, digitized polygraph signals are transformed into more fundamental signals. These fundamental signals are then subjected to standardization, a critical step. The standardized signals then have certain features extracted at each question. The features for all of the relevant questions are then standardized against the features for all of the control questions. From each of the resulting standardized relevant features, a percentile is taken. Finally, a logistic regression model (logit) converts this set of percentile features into a probability of deception. This system has been adapted for use with the Windows operating system.

Patent Status: U.S. patent(s) 5,327,899 issued.

Mr. J. E. Dietz
Phone: (443) 778-2782