Balanced experimental designs, in which the number of treatment and control units are the same, do not maximize power subject to a cost constraint when treatment units are more expensive than control ones. Despite this, such balanced designs are the norm in economics. This paper describes...

We evaluate the impact on crime of a localized policing experiment that depenalized the possession of small quantities of cannabis in the London borough of Lambeth. Such a policy can: (i) impact the demand for cannabis in Lambeth as users move there to purchase cannabis; (ii) enable the Lambeth...