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Web Survey Bibliography

Title Simple Approaches to Estimating the Variance of the Propensity Score Weighted Estimator Applied on Volunteer Panel Web Survey Data--a Comparative Study
Year 2005
Access date 27.10.2005

Survey data collection from volunteer Web panels is growing in popularity. While this practice has obvious advantages in terms of costs, flexibility and speed, estimates from such data for characteristics of the general population may be seriously biased due to low Web penetration in the general population, nonprobability samples, and high nonresponse rates. The propensity score adjustment was introduced as a possible solution of the selection bias in observational studies. Its modification, propensity score weighting using a reference survey, has been suggested as a remedy of problems in volunteer panel Web surveys.  We can derive a propensity score weighted estimator that is less biased, if not unbiased, of the parameter of interest, under certain model assumptions.  However, there is no evident solution for its variance estimation. In the present study, some simple variance estimators are compared: (1) the estimator applicable when a poststratified point estimator is used, (2) a variation of (1) available in SUDAAN, (3) a model-based estimator, and (4) a jackknife estimator. Our study focuses on the performance of the estimators in a simulation applying distributions of key demographic variables from a real volunteer panel Web survey in the sample selection.  

Year of publication2005
Bibliographic typeConferences, workshops, tutorials, presentations