Combining mobile phone and landline phone samples. A practical application of the dual frame approach

Abstract

The difficulty in contacting very Mobile people, increasing non-response as a result of the flood of marketing and cold calls, and the growing number of people who use mobile phones exclusively are all reasons to argue in favor of using a sampling structure that combines mobile phone and landline phone sample designs to ensure the quality of telephone surveys. Currently, a dual-frame concept of landline and mobile phone samples is being put to the test. In this context, this article examines the effects on the distribution of politically relevant variables in current surveys of the Forschungsgruppe Wahlen, where mobile phone numbers are included in random telephone samples.