ABSTRACT
The understanding of criminal behavior sought by PCC is empirical, theoretical, and practical. In this chapter, the empirical methods used to understand criminal behavior are described and summarized. Four major research designs are presented: (1) cross-sectional, (2) longitudinal, (3) multi-wave longitudinal, and (4) randomized experiments. The first three types of designs provide information about the correlates of criminal conduct (simple correlation, predictors, dynamic risk factors). However, we ultimately seek the causes of criminal behavior and for this we need randomized experimental research.
No single study, even a randomized experiment, can provide the “true” value of research concerning criminal behavior. Meta-analysis, because it involves many investigations, sometimes numbering in the hundreds, provides an unbiased and quantitative assessment of a body of literature. This chapter provides a primer on the importance of meta-analysis and the common statistics used in building knowledge.
