ABSTRACT
Accumulated evaluative evidence provides information supporting or contradicting the original theory. This chapter considers why design alone is inadequate for learning and argues that strong theoretical foundations are required. It looks at the basic elements of crime prevention evaluations. Formal evaluations attempt to establish a causal connection between an intervention and some outcome. The intervention is the package of actions whose effectiveness the evaluation is supposed to determine. It is a package because all interventions involve a collection of actions. Consider an evaluation of the effectiveness of landlord interventions on curbing crime at drug dealing locations. The importance of mechanism is often overlooked in criminological evaluations, though R. Pawson and N. Tilley place considerable emphasis on it. If the evaluator had tested the effectiveness of police raids, or organizing tenants, or counseling drug dealers and claimed that these were manifestations of place management, the evaluator’s claim would be invalid and the evaluation would have no implications for place management.
