Recruiting large online samples in the United States and India: Facebook, Mechanical Turk, and Qualtrics

TLDR

The study compares online recruitment methods—Facebook, MTurk, and Qualtrics—in India and the U.S. The authors compared 7,300+ participants from each platform and country against national benchmarks on demographics, political attitudes, knowledge, cooperation, and experimental replication. In the U.S., MTurk is fastest and cheapest, Qualtrics most representative, and Facebook enables targeted sampling; in India samples are less representative, though Facebook provides broad geographic coverage; convenience samples can validly capture partisan moderation of treatment effects but are generally unrepresentative on political variables, limiting external validity.

Abstract

Abstract This article examines online recruitment via Facebook, Mechanical Turk (MTurk), and Qualtrics panels in India and the United States. It compares over 7300 respondents—1000 or more from each source and country—to nationally representative benchmarks in terms of demographics, political attitudes and knowledge, cooperation, and experimental replication. In the United States, MTurk offers the cheapest and fastest recruitment, Qualtrics is most demographically and politically representative, and Facebook facilitates targeted sampling. The India samples look much less like the population, though Facebook offers broad geographical coverage. We find online convenience samples often provide valid inferences into how partisanship moderates treatment effects. Yet they are typically unrepresentative on such political variables, which has implications for the external validity of sample average treatment effects.