Supplementing RDD Surveys with Web-Based Survey Data
Krotki, K. (2006, August). Supplementing RDD Surveys with Web-Based Survey Data. Presented at Joint Statistical Meetings, Seattle, WA.
With declines in response rates it becomes important to seek cost-effective alternatives to the telephone survey mode. One candidate is the web-based survey which, even though it is not based on a probability sample, comes from a frame that in many respects resembles the entire population. Furthermore, the web-based survey is much less expensive than RDD. We study the differences between the RDD and web-based survey data, we develop methodologies for combining the two sets of weights in a way that accurately reflects the underlying populations, and we develop design- and model-based strategies for the estimation process including variance calculations and significance testing. Specifically, these concepts will be developed using data from the 2004 Ohio Adult Tobacco Survey, which consists of approximately 2,000 completed RDD interviews and 6,000 web-based interviews.