Accuracy Of Polygraph Test

An underlying problem is theoretical.

Accuracy of polygraph test. The validity of polygraph testing means in nontechnical terms accuracy of the test in detecting deception and truthfulness. Actually the polygraph test detects changes in psychological behaviors and signals. There are as a result a number of different forms. An examiner s interpretation is subjective.

Polygraph techniques in which multiple issues were encompassed by the relevant questions produced an aggregated decision accuracy of 85 confidence interval 77 93. Saxe and israeli psychologist gershon ben shahar 1999 note it may in. Also scientific reviews indicate that diagnostic tests have the accuracy of 89 with a confidence range of 83 to 95. The accuracy i e validity of polygraph testing has long been controversial.

An honest person may be nervous when answering truthfully and a dishonest person may be non anxious. According to research noted by the american polygraph association apa website on polygraph validity. Studies have shown that when a well trained examiner uses a polygraph he or she can detect lying with relative accuracy. The belief underpinning the use of the polygraph is that deceptive answers will produce physiological responses that can be.

Published studies show that several valid polygraph methods have the accuracy of over 90 with a 95 confidence. Then it would be possible to check the polygraph s responses against reality in a high stakes situation if the examiner was unaware. The problem of assessing polygraph validity is especially difficult not only because polygraph tests take a number of forms but also because validity has different dimensions and can be measured in a number of ways. In a scientific sense polygraph tests can be said to be valid.

The data show that techniques intended for event specific single issue diagnostic testing produced an aggregated decision accuracy of 89 confidence interval of 83 95 with an estimated inconclusive rate of 11. A polygraph popularly referred to as a lie detector test is a device or procedure that measures and records several physiological indicators such as blood pressure pulse respiration and skin conductivity while a person is asked and answers a series of questions. On the other hand the. According to richard wiseman professor of the public understanding of psychology at the university of hertfordshire testing the accuracy is difficult because you can t simply ask a criminal whether he was lying or not the only method would be to use polygraphs in cases where the true answer had already been established using other evidence.

In scientific terms the aim of the polygraph test is not detecting lie. Also there are few good studies that validate the ability of polygraph procedures to detect deception. A polygraph test may be able to detect in some general way that someone is being deceptive but not be able to accurately link the deception with any specificity to a criminal act.