Measuring Crime: Behind the Statistics

Abstract: In 1915, the Chicago City Council asked statistician Edith Abbott to report “upon the frequency of murder, assault, burglary, robbery, theft and like crimes in Chicago.” Her report, drawing on published and unpublished statistics from the courts, probation office, house of correction, and police department, set the stage for subsequent collections and evaluations of crime statistics. Her conclusions—that statistics’ quality depend on the systems of data collection and that multiple sources of data are needed to study crime—hold today.

Drawing on Abbott’s insights, I set out eight questions to ask about a statistic before you rely on it. I then go through these questions for three sources of statistics about sexual assault: the Uniform Crime Reports, the National Crime Victimization Survey, and the National Intimate Partner and Sexual Violence Survey.

Bio: Sharon Lohr is a vice president and senior statistician at Westat in Rockville, Maryland. Previously, she was dean’s distinguished professor of statistics at Arizona State University. Her research has focused on survey sampling, hierarchical models, small-area estimation, missing data, and design of experiments. She is a fellow of the American Statistical Association and an elected member of the International Statistical Institute. She was the inaugural recipient of the Washington Statistical Society’s Gertrude M. Cox Statistics Award for contributions to the practice of statistics and a recipient of the society’s Morris Hansen Lecture Award. She was recently selected to present the Deming Lecture at the Joint Statistical Meetings. She has a Ph.D. in statistics from the University of Wisconsin–Madison.