Revealing Longitudinal Heterogeneity in Police Clearances: An Application of Group-based Trajectory Modeling

• In Event: Identifying Effective Police Investigative Practices: A National Study Using Trajectory Analysis

Abstract

Using clearance rate data for selected index offenses from the 100 largest agencies in the United States for the period 1980 to 2013 we seek to determine if there are clear group trajectories using group based trajectory modeling techniques. Following that analysis, we consider the issue of classifying agencies across offense trajectories by comparing hard counts, weighted counts, and multi-trajectory modeling. Results are used to determine if there agency level differences in clearance of serious crime.

Author

• Thomas Lind Scott, University of Maryland