140 – Address-Based Telephone RDD and Cell Phone Sampling
Scope and Coverage of Landline and Cell Phone Numbers Appended to Address Frames
Rachel Harter
RTI International
Joseph McMichael
RTI International
With the commercial availability of address-based sampling frames sourced from the U.S. Postal Service files, address-based sampling is offered as a higher coverage alternative to random digit dialing samples. Telephone contacts and data collection are less expensive than their in-person counterparts, however, so some vendors append telephone numbers to addresses where their sources indicate a match. The coverage of the addresses with telephone numbers is far from complete, leading to an increase in mixed mode surveys, where the alternative is often in-person. The greater the coverage of the telephone numbers, the lower the cost of the survey. In this paper we explore the availability of landline and cell phone numbers appended to a sample of 12 million addresses from the Computerized Delivery Sequence file licensed from Valassis. We summarize the phone coverage by geography, geographical demographics, and address characteristics, putting aside the issues of address coverage of the household population and the accuracy and viability of the telephone numbers themselves. Knowledge of phone coverage for subpopulations increases the information available to sample designers.
