Effects of Nonresponse, Measurement, and Coverage Bias in Survey Estimates of Voting

Objective The objective is to estimate the relative contributions of nonresponse, coverage, and measurement biases in survey estimates of voting. Methods We survey 3,000 Boston‐area households sampled from an address‐based frame matched, when possible, to telephone numbers. A two‐phase sampling design was used to follow up nonrespondents from phone interviews with personal interviews. All cases were then linked to voting records. Results Nonresponse, coverage, and measurement‐biased survey estimates at varying stages of the study design. Coverage error linked to missing telephone numbers biased estimates that excluded nonphone households. Overall estimates including nonphone households and nonrespondent interviews include 25 percent relative bias equally attributable to measurement and nonresponse. Conclusion Bias in voting measures is not limited to measurement bias. Researchers should also assess the potential for nonresponse and coverage biases.