Book chapter

Laboratory Versus Field Experiments in Political Decision Making Research (2020)

in: Oxford Research Encyclopedia of Politics


It can be difficult for political scientists and economists to know when to use laboratory experiments in their research programs. There are longstanding concerns in economics and political science about the external invalidity of laboratory results. Making matters worse, a number of prominent academics recommend using field experiments instead of laboratory experiments to learn about human behavior because field experiments do not have the same external invalidity problems that plague laboratory experiments. The criticisms of laboratory experiments as externally invalid, however, overlook the many advantages of laboratory experiments that derive from their external invalidity. Laboratory experiments are preferable to field experiments at examining hypothetical scenarios (e.g., When automated vehicles dominate the roadways, what principles do people want their automobiles to rely on?), at minimizing erroneous causal inferences (e.g., Did a treatment produce the reaction researchers are studying?), and at replicating and extending previous studies. Rather than being a technique that should be abandoned in favor of field experiments, political scientists and economists should embrace laboratory experiments when testing theoretically important but empirically unusual scenarios, tracing experimental processes, and reproducing and building on prior experiments.