A Visicalc program for estimating the area under a receiver operating characteristic (ROC) curve.

The area under the ROC curve interests us as a method for analyzing discrimination or detectability. One can assess a diagnostic test or probability assessor with respect to its degree of discrimination. The area under the ROC curve gives us the probability of correctly identifying abnormal from normal in a forced-choice, two-alternative problem. Previous methods used for calculating the area involved maximum likelihood estimation on a mainframe or minicomputer. This paper demonstrates an adaptation of a recently published nonparametric method for estimating the area. This adaptation takes advantage of electronic spreadsheet software and may be used on most (if not all) microcomputers. The paper develops the construction of the program needed for the necessary calculations.