Studies administered under RIPS primarily fall under the rubric of experimental research. While some investigators have used RIPS as a means of pretesting items for use in larger-scale surveys, most investigators have relied on the experimental method in their research.
Our emphasis on experimentation reflects an ongoing movement in the discipline of political science. Appropriate experimental designs offer researchers unparalleled control over stimuli, wide latitude in measurement, and, above all, internal validity: the ability to identify causal relationships between a stimulus and a response. Conducting experiments in a laboratory setting can ensure internal validity, due to the superior control over environmental conditions that laboratories offer, and laboratory settings may be preferred due to the wider range of questions, tests, and tasks that can be administered compared with studies in the field. For example, investigators in our laboratory have collected millisecond response latency data, have administered sophisticated audio-visual treatments, and have even had subjects play the dictator game. Although in the vast majority of our studies, subjects answer questions individually, recently, investigators have conducted multi-agent experiments as well, in which subjects are given the opportunity to consult with each other electronically as part of the study.
Most of the laboratory studies conducted under RIPS rely on convenience samples of undergraduate students at Vanderbilt. The subject pool is typically drawn from both lower-division and upper-division courses in the Department of Political Science (with occasional participation by other departments on campus). Students receive course credit for participating in the studies. Some RIPS studies have also drawn from campus employees and residents of local towns (who are paid for their participation).
Mode of Interview
Studies under RIPS use a self-administered computer-based survey mode. Occasionally, investigators have supplemented the computer-based mode with other tasks, including dictator games and paper-and-pencil open-ended responses.
For our computer-based instrumentation, we primarily use Inquisit v3.0, which allows for administration of close-ended and open-ended survey questions as well as presentation of images and video.