Randomized Experiments in Criminology and Criminal Justice

Randomized experiments are a type of experimental design that uses random assignment to gain equivalence between groups in a study. They are used most often to evaluate the impact of interventions on outcomes. This entry summarizes the rationale for a randomized experiment, provides the essential components of the design and an example from the policing literature, and briskly highlights its history and status as the “gold standard” for evaluation research. The entry concludes with a description of barriers to experiments and some of the problems in the field that threaten the design.