MENTAL ABILITY CAN BE MEASURED BY THE PROBLEM-SOLVING PROCESS RATHER THAN BY THE NUMBER OF CORRECT SOLUTIONS. THE OBJECTIVES OF THIS STUDY ARE--(1) TO DEVELOP AND STUDY PROPERTIES OF MEASUREMENT TECHNIQUES WHICH REVEAL THE PROBLEM-SOLVING PROCESS, (2) TO DEVELOP WAYS OF DESCRIBING INDIVIDUALS THROUGH THEIR PROBLEM-SOLVING PROCESSES, AND (3) TO COMPARE CONCEPTS FROM INFORMATION PROCESSING PSYCHOLOGY WITH THE STUDY OF INDIVIDUAL DIFFERENCES. THE SUBJECT PRESENTED WITH A PROBLEM PROVIDES HIS PRESENT ANALYSIS, A LIST OF ADDITIONAL INFORMATION NEEDED AND SUGGESTED INFORMATION SOURCES, AND A STATEMENT OF HIS CURRENT PROBLEM-SOLVING STRATEGY. FEEDBACK, RELATED TO THE INFORMATION REQUESTED, IS PROVIDED. THE WHOLE PROCESS IS REPEATED TWICE. THE SCORING SYSTEM EMPHASIZES THE TYPE OF ANALYSIS, THE TYPE AND AMOUNT OF INFORMATION SOUGHT, AND THREE TYPES OF STRATEGY. THE RESPONSE PATTERN IS DESCRIBED IN TERMS OF NINE CHARACTERISTICS. SPECIAL PROBLEMS ARE DESIGNED TO YIELD INFORMATION ABOUT THE SUBJECT'S ORGANIZATION OF INFORMATION USED AND PROBLEM-SOLVING STRATEGY. CHARACTERISTICS OF THE PROBLEMS AND THE CLASSIFICATION OF SUBJECTS ARE DESCRIBED. PATTERNS OF ANALYSES, INFORMATION SEEKING, AND STRATEGY VARY ACCORDING TO THE PROBLEM-SOLVING STATE, THE STUDENT'S ABILITY, AND HIS COLLEGE MAJOR. ORGANIZATION OF INFORMATION CAN BE INFERRED BY STUDY TECHNIQUES. INDIVIDUALS CAN BE MATCHED WITH PROBLEM-SOLVING MODELS. THE CONCLUSIONS ARE DISCUSSED. (AUTHOR/PS)