Reverse Directory Sampling

A reverse directory is a residential telephone directory that has been converted from a surnamed alphabetically ordered listing to a street name ordered listing. Reverse directory sampling refers to the selection of a sample of address listings—which may be residential, nonresiden-tial, or both—from a reverse directory. The selection of a sample from a reverse directory involves the random selection of these address listings. This can be accomplished by determining the number of pages in the directory and first selecting a systematic random sample of pages. For each selected page, one or more address listings can then be selected also using systematic random sampling. This approach assumes that the pages in the reverse directory contain approximately the same number of address listings.

Today, such manual sampling procedures are rarely used. Telephone directories are key-entered so that computerized databases of telephone directories are available through various commercial sources. Geographic codes (such as county FTPS [Federal Information Processing Standard] code), census tract number, block group number, and zip code are assigned to each telephone number in the database. This makes it possible to draw a random sample of telephone numbers from a specific geographic area (e.g. a single zip code). The survey researcher must recognize that such samples exclude telephone households with unlisted telephone numbers and households without a landline and therefore may contain considerable coverage error.