Accession Number : AD0691239

Title :   AIDED HUMAN PROCESSING OF INCONCLUSIVE EVIDENCE IN DIAGNOSTIC SYSTEMS: A SUMMARY OF EXPERIMENTAL EVALUATION.

Descriptive Note : Final rept. 1 Oct 65-1 Jun 66,

Corporate Author : OHIO STATE UNIV COLUMBUS HUMAN PERFORMANCE CENTER

Personal Author(s) : Schum,David A. ; Southard,Jack F. ; Wombolt,Louise F.

Report Date : MAY 1969

Pagination or Media Count : 68

Abstract : The report describes three experimental evaluations of a procedure for aiding men in combining probabilistic (inconclusive) information. The procedure is called 'Semi PIP' (Probabilistic Information Processing). In the semi PIP procedures, a computer relieves man of part of the task of combining probabilistic evidence. The experiments involved a simulated military threat-diagnosis task in which probabilistic data are used as a basis for deciding among alternative hypothesized threats. The Semi PIP was compared with an unaided procedure called POP (Posterior Probability), and both procedures compared with a mathematically ideal combination of evidence (Bayes' theorem). It was found from the three experiments that: (1) overall, the difference between Semi PIP and POP performance was very slight; (2) POP was best when a small total amount of evidence accumulated very rapidly; and, (3) Semi PIP was slightly, though consistently, superior when the total amount of evidence to be evaluated was large, when the total diagnostic impact in a set of evidence was large, or when both these conditions prevailed. Specific implications of the results for diagnostic system design and for research on basic human inference processes are summarized. A glossary of key terms from Bayesian decision theory is included in the report. (Author)

Descriptors :   (*DECISION MAKING, *MAN MACHINE SYSTEMS), (*THREAT EVALUATION, MAN MACHINE SYSTEMS), PERFORMANCE(HUMAN), PROBABILITY, STATISTICAL DATA, DATA PROCESSING, STATISTICAL DISTRIBUTIONS, DECISION THEORY, SYSTEMS ENGINEERING, DIAGNOSIS(MEDICINE), SIMULATION, MATHEMATICAL PREDICTION

Subject Categories : Psychology
      Military Operations, Strategy and Tactics
      Human Factors Engineering & Man Machine System

Distribution Statement : APPROVED FOR PUBLIC RELEASE