AN ATTEMPT IS MADE TO ASSESS THE ECONOMICS OF COMPUTER ASSISTED INSTRUCTION (CAI) VERSUS TRADITIONALLY ADMINISTERED INSTRUCTION (TAI) IN CONTROLLING THE STRUCTURE OF THE LEARNER'S STIMULUS ENVIRONMENT IN TEACHING AND TRAINING SITUATIONS. THERE IS A DISCUSSION OF THE NEED FOR A SOUND, OBJECTIVE ECONOMIC APPRAISAL OF THE VALUE TO SOCIETY OF INCREMENTS IN THE BREADTH AND DEPTH OF EDUCATION IN THE POPULATION, AND OF THE INFLUENCE OF VARYING RATES AT WHICH THESE INCREMENTS ARE BROUGHT ABOUT. THE NECESSITY FOR RELIABLE, OBJECTIVE INFORMATION CONCERNING COST DATA IS EMPHASIZED. PROJECTED COMPARISONS OF COST AND EFFECTIVENESS BASED ON THE ASSUMPTION OF EQUAL EFFECTIVENESS FOR CAI AND TAI ARE DISCUSSED FOR CIVILIAN AND MILITARY INSTRUCTION. IN PARTICULAR, THE FIVE STUDIES OF MILITARY TECHNICAL TRAINING STRESS COSTS PER STUDENT HOUR, AND ILLUSTRATE THE PROBLEM OF OBTAINING ACCURATE COST FIGURES FOR MILITARY INSTRUCTIONAL EXPENDITURES. (ALSO INCLUDED ARE FIVE FIGURES, EIGHT TABLES, AND 21 REFERENCES.) THIS DOCUMENT AD-656-613, IS AVAILABLE FROM THE CLEARINGHOUSE FOR FEDERAL SCIENTIFIC AND TECHNICAL INFORMATION, SPRINGFIELD, VA. 22151. MICROFICHE $0.65, HARD COPY $3.00. (AUTHOR/LY)