This course presents quantitative approaches to measurement in the psychological and social sciences. It is designed for doctoral students and is offered jointly by the Departments of Mental Health and Biostatistics. Examples will be drawn from the social sciences, including stress and distress, social class and socioeconomic status, depression, functional impairment and disability. The instructional method consists of presentations by the instructors, hands-on sessions in the computer laboratory, and assigned problem sets. Problem sets will require active manipulation of datasets provided by the instructors, using standard statistical packages such as Stata and M+. You may use alternate statistical packages if you wish, but we may not be able to answer questions about using those packages, and the output in your problem sets must be labeled clearly. This course is part of a two-quarter series on Statistics for Psychosocial Research, oriented towards structural equation models and related methods, taught jointly by the Departments of Mental Health and Biostatistics. The first quarter concentrates on measurement, and the second quarter on structural models. Credit for this course may be obtained without enrolling in the following course, but this course, or permission of the instructor, is required for enrollment in the second quarter course.