TELEPHONE INTERVIEWS: COST-EFFECTIVE METHOD FOR ACCURATE TRAVEL SURVEYS

A residential travel survey of a seven-county regional area was designed and conducted by Anderson, Niebuhr & Associates, Inc. for the Metropolitan Council of the Twin Cities Area, Saint Paul, Minnesota, between September 1982 and March 1983. A random sample of households was selected from directories of listed telephone numbers using computer generated random digits. Preliminary telephone interviews were conducted. If the household member agreed to have the household participate in the survey, general household data were collected and a day for logging travel information was selected. A cover letter, travel cards, and instruction cards were mailed to the households participating in the travel survey. Reminder calls were made to these households on the evening preceding the selected travel day to remind them to complete the travel diaries and to answer any questions. On the day after the travel day, households were again called to collect the travel data. The survey data were edited and coded by the staff of the Metropolitan Council. The primary purpose of the survey was to update, not repeat, a previous 1970 survey. Questions were limited to key data needed to verify findings of the earlier survey. Both the brief survey content and the method of data collection resulted in substantial cost savings while retaining acceptable representation and accuracy.