Field Experiments in Political Science and Public Policy ─ Practical Lessons in Design and Delivery

An experiment occurs when people manipulate the world in order to understand causal relationships. The secret in science is to have precise control of the different elements to the experiment, and then to measure carefully what happens during and after the intervention. It is this precision of knowledge based on careful measurement that is the big attraction of experiments, and explains why other disciplines have sought to emulate the experimental method.

Peter John’s latest book is an introduction to experimentation in political science and public policy. It first defines experimentation and offers historical context, and then moves on to review key features of the statistical method, all the while linking experimentation to core ideas in politics and public policy. Yet rather than functioning as just a research methods text, the book instead is an invitation to the intellectual project and research program of experimentation, which has large ramifications for how researchers and students of political science and public policy carry out their work more generally. John argues that experiments offer a more valid way of testing for cause and effect relationships in politics and policy because of the superior claim for internal validity. John also concludes that most researchers and policy-makers can do experiments without a large amount of training in statistics or research methods, and that most methods of analysis and design of experiments are well known by statisticians and medical researchers so do not need a great deal of adaptation to the world of political science and public policy.

The book is about the project of social science as a whole, and the way which certain ways of knowing about the world can serve its overall purpose. Overall, John claims that a more experimental approach to studying topics in political science and public policy can help academics re-discover the core mission of their subjects and sharpen their focus on the tasks at hand.

Peter John is Professor of Political Science and Public Policy in the Department of Political Science, University College London. He is an expert on the theory of public policy, and has pioneered the use of experiments in the study of civic participation in the UK. He has an interest in the use of research methods in public policy.