Measuring the Accuracy of Diagnostic Systems
Diagnostic systems are all around us. They are used to reveal diseases in people, malfunctions in nuclear power plants, flaws in manufactured products, threaten ing activities of foreign enemies, collision courses of aircraft, and entries of burglars. Such undesirable conditions and events usually call for corrective ac tion. Other diagnostic systems are used to make judicious selection from many objects. Included are job or school applicants who are likely to succeed, income tax returns that are fraudulent, oil deposits in the ground, criminal suspects who lie, and relevant documents in a library. Still other diagnostic systems are used to predict future events. Examples are forecasts of the weather and of economic change.