In the 1909 American Political Science Association presidential address, A. Lawrence Lowell claimed: “We are limited by the impossibility of experiment.
The first experiment in political science is regarded to be Harold Gosnell's 1924 study on voter turnout in Chicago.
[3] In this experiment, he randomly assigned districts to receive information on voter registration and encouragement to vote.
[7] In the 1980s, computer-assisted telephone interviewing began to appear and was used for the collection of experimental data—the advances in the technology led to the initial rise of experiments.
[8] Experimentation was becoming part of the political scientist's toolkit during this period due to the development of information technology.
In 2010, the Experimental Research section of the American Political Science Association held its first conference.
[10] In 2012, Bond et al.'s experiment delivered political mobilization messages to 61 million Facebook users.
They aimed to explore whether an “I Voted” widget that announced one's election participation to others increased turnout among Facebook users and their friends.
[11] Today's mature social media provide the opportunity to intervene experimentally with a vast capacity population.
[12] Current experts in experimental methodology in political science include Rebecca Morton and Donald Green.
[16] Alternatively, validity is the extent to which we can believe that the empirical inference can reflect the real laws of human society.
[18] For example, high construct validity means that the research design has a higher degree of fit with the theory being studied.
[17] Internal validity refers to the degree to which knowledge inferences based on empirical research approximate the actual attitudes or behavioural patterns of the target population.
Students are often a convenient sample in lab experiments because they are easy to participate in and able to follow the experimental instructions reliably.
Risk aversion, time preference (patience), altruism, cooperation, competition, and in-group discrimination are the most common measures.
Experimental research methods in political science have unavoidable ethical questions: Can humans be used for experiments?
The experimental process itself is not the only way political science research activities affect human life.
[29] Political scientists are increasingly dissatisfied with just confirming the strength of the relationship between various factors, and gradually devote themselves to the discussion of causal effects and mechanisms among variables.
[31] In a modern society with highly developed information technology, it is becoming more and more efficient and low-cost to control and collect data by conducting experiments.
These social media and online blogs transmit a large amount of political information and make it more accessible to the public.
The distinctive feature of current research is that it focuses on some specific social groups, such as unmarried people, students, ethnic minorities, etc.
More and more scholars have begun to use a mixture of different methods to make up for the shortcomings of a single experimental approach.