Field experiments have grown significantly in prominence over the past decade. In this essay, we provide a summary of the major types of field experiments, explore their uses, and describe a few examples. We show how field experiments can be used for both positive and normative purposes within economics. We also discuss more generally why data collection is useful in science, and more narrowly discuss the question of generalizability. In this regard, we envision field experiments playing a classic role in helping investigators learn about the behavioral principles that are shared across different domains.
