A MEASURING OPERATION IS A SAMPLE FROM A UNIVERSE OF ADMISSIBLE OBSERVATIONS....GENERALIZABILITY STUDIES ESTIMATE THE MAGNITUDE OF THE DISCREPENCIES LIKELY TO ARISE UNDER A GIVEN MEASURING PROCEDURE, AND PROVIDE FORMULAS FOR ESTABLISHING INTERVAL AND POINT ESTIMATES OF THE UNIVERSE SCORE. A MULTIFACET GENERALIZABILITY ANALYSIS DEPARTS IN SEVERAL WAYS FROM THE CLASSICAL STUDY OF RELIABILITY. IT RECOGNIZES THAT OBSERVATIONS CAN BE DIFFERENTIATED WITH REGARD TO ANY FACETS....THE CLASSICAL ASSUMPTION OF COMPLETE EQUIVALENCE...IS ABANDONED. ATTENTION IS GIVEN TO THE ABSOLUTE MAGNITUDE OF THE UNIVERSE SCORE, THE ERROR OF MEASUREMENT, AS WELL AS TO INDIVIDUAL DIFFERENCES. THE GENERALIZABILITY STUDY SHOWS HOW TO ALTER THE EXPERIMENTAL DESIGN...SO AS TO OBTAIN OPTIMAL EFFICIENCY....THE PRESENT MONOGRAPH ELABORATES ON THE THEORY AS PRESENTED BY GLESER ET. AL. (1965) AND DEMONSTRATES THE APPLICATION OF THE THEORY TO DATA FROM A VARIETY OF INVESTIGATIONS IN EDUCATION AND PSYCHOLOGY. THIS DOCUMENT, LIMITED IN CIRCULATION, IS AVAILABLE FROM GOLDINE C. GLESER, DEPT. OF PSYCHIATRY, CENTRAL PSYCHIATRIC CLINIC, GENERAL HOSPITAL, UNIV. OF CINCINNATI MEDICAL SCHOOL, CINCINNATI, OHIO 45229 OR FROM LEE J. CRONBACH C/O PROF. H. AZUMA, FACULTY OF EDUCATION, UNIV. OF BUNKYOKU, TOKYO, JAPAN (TO JUNE 1, 1968--SUBSEQUENTLY, TO STANFORD). THE AUTHORS ASK THAT THE MATERIAL NOT BE FURTHER REPRODUCED, QUOTED, OR CITED WITHOUT COMMUNICATING WITH ONE OF THEM. (AUTHOR)