2.6: Emerging Wave- Experimental Political Science

Learning Objectives

By the end of this section, you will be able to:

• Comprehend the role of experiments in political science
• Understand the reluctance of political scientists to embrace experimentation

An emerging wave of methodology in the discipline is that of experimental political science. The value of this method has increased in the past few decades as true experimentation can establish causality, or to definitively say that variable X causes variable Y. This is also referred to a causal relationship, or a causal mechanism. In other methods of political science, such as a quantitative analysis of data sets, research generally leads only to correlational relationships, which are much weaker than causal relationships. In correlational relationships, one can only show that there is a relationship between two or more variables. And just because a relationship exists between variables does not mean that additional relationships exist between the variables that could provide alternative explanations. Hatcher (2013) accepts that there may be an “observed correlation that differs from the research hypothesis”.

Out of the desire to provide stronger evidence for cause and effect, political scientists have begun using experimental methods. Experiments are understood by McDermott (2002) to “refer primarily to laboratory studies in which investigators retain control over the recruitment, assignment to random conditions, treatment, and measurement of subjects”. McDermott points out that experiments diminish the effect of bias as it focuses on standardization in the research process. Thus, by having exact procedures, measures, and analyses, researchers can manipulate a variable of interest, repeat the experiment among many subjects, providing for strong internal validity. The standardization of the techniques allows for the replication of the experiment by other scholars, and thus provides for a measure of external validity (more on this below). This then allowed the researchers to draw causal inferences.

Experimental political science has become popular in political psychology and in understanding voter behavior. It has not yet caught on in the overall discipline. Even though experimentalism is part of the behavioral wave, there is a concern regarding the overall external validity and the ability to generalize beyond the studied population. While manipulation of a variable may show a statistical effect in an experiment with students, will it have the same effect with the larger population? McDermott (2002) posits that political scientists are being too critical and failing to understand that experimentalists do not make larger claims about human behavior from limited study. They understand that external validity is made over time, with quite a bit of replication. In addition, experiments are intended to test theories and build hypotheses, not generate broader conclusions.

Additionally, a peer-review journal, the Journal of Experimental Political Science (JEPS), was founded in 2014 to help foster additional interest and research using experimental and quasiexperimental methods. The editors of JEPS explain (Mann et. al) that they define “experimental methods broadly: research featuring random or quasi-random assignment of subjects to different treatments in an effort to isolate causal relationships in the sphere of politics. JEPS embraces all of the different types of experiments carried out as part of political science research, including survey experiments, laboratory experiments, field experiments, lab experiments in the field, natural and neurological experiments.”