Experimental methods have recently been used to evaluate environmental policy instruments, in particular – and most suitably, it seems – emissions trading programs of various designs. Some studies have focused on domestic emissions trading programs, while others have focused on international...

'Until not much more than 20 years ago, economists frequently lamented the fact that they were limited in their empirical analyses to statistical assessments of market behavior, because controlled economic experiments were (thought to be) infeasible, unethical, or both. Much has changed in the...