مقایسهٔ روش‌ها

	Expert Survey	Survey Experiment	Vignette Experiment
حوزه	Political Science	Political Science	Political Science
خانواده	Process / pipeline	Process / pipeline	Process / pipeline
سال پیدایش	—	2011	—
پدیدآور	Comparative party-positioning research (Castles & Mair; Chapel Hill team)	Experimental political science; synthesized by Diana Mutz	Survey and social-psychological research traditions
نوع	Survey of subject-matter experts to measure latent positions	Randomized experiment embedded in a survey	Randomized experiment using short described scenarios
منبع بنیادین	Bakker, R., de Vries, C., Edwards, E., Hooghe, L., Jolly, S., Marks, G., Polk, J., Rovny, J., Steenbergen, M., & Vachudova, M. A. (2015). Measuring Party Positions in Europe: The Chapel Hill Expert Survey Trend File, 1999–2010. Party Politics, 21(1), 143–152.	Mutz, D. C. (2011). Population-Based Survey Experiments. Princeton, NJ: Princeton University Press. ISBN: 9780691144528	Atzmüller, C., & Steiner, P. M. (2010). Experimental Vignette Studies in Survey Research. Methodology, 6(3), 128–138.
نام‌های دیگر	Expert judgment survey, Party expert survey, Chapel Hill Expert Survey, Expert placement survey	Population-based survey experiment, Survey-embedded experiment, Question-wording experiment, Framing experiment	Vignette study, Experimental vignette, Scenario experiment, Text-vignette experiment
مرتبط	4	4	3
خلاصه	An expert survey measures latent political quantities — most often parties' positions on policy dimensions — by asking a panel of country and subject-matter experts to place the objects of interest on structured numerical scales. Averaging many experts' judgments yields position estimates, while the spread across experts provides a built-in measure of uncertainty and reliability. The Chapel Hill Expert Survey is the leading example, producing comparable measures of European parties' positions on ideology, European integration, and many specific issues over time.	A survey experiment embeds a randomized experiment inside a survey: respondents are randomly assigned to different versions of a question, frame, or stimulus, and their answers are compared to estimate a causal effect. By combining the internal validity of randomization with the representative samples and rich measurement of survey research, survey experiments — especially population-based ones — let political scientists draw causal inferences about how information, framing, or message attributes shape public attitudes and behavior.	A vignette experiment presents respondents with a short, carefully constructed description of a person, situation, or scenario — a vignette — in which one or more features are experimentally manipulated, and then asks for a judgment, attitude, or intended action. By randomizing which version of the scenario each respondent reads, the researcher isolates the causal effect of each manipulated feature on the elicited judgment, combining the realism of a concrete scenario with the causal leverage of an experiment.