Experimental Identification of Causal Mechanisms.

Experimentation is a powerful methodology that enables scientists to empirically establish causal claims. Even in social sciences where traditionally observational studies were dominant, experiments are becoming increasingly common. However, one general criticism of experimental methodology is that experiments merely provide a black-box view of causality -although experiments can identify an average causal effect, they cannot explain how such an effect comes about. If true, this represents a serious limitation of experimentation, especially for social science research whose main goal is to identify causal mechanisms. In this paper, we first establish that two existing approaches commonly employed by social scientists to address this critique suffer from serious methodological problems. To overcome this limitation, we consider alternative experimental designs that can be used to help identify causal mechanisms. Finally, we discuss the situations in which these experimental designs are applicable and illustrate their use by applying them to a behavioral neuroscience experiment. [ABSTRACT FROM AUTHOR]