In an effort to counter the problem of noncooperation, survey organizations
are offering incentives to respondents with increasing frequency, some at
the outset of the survey, as has traditionally been done in mail surveys, a
nd some only after the person has refused, in an attempt to convert the ref
usal. This article reports on a series of experiments carried out over a pe
riod of about 2 years with a monthly telephone survey, the Survey of Consum
er Attitudes, in an effort to increase response rates or reduce interviewer
effort. We report on experiments with prepaid versus promised incentives;
advance letters; and advance letters with prepaid incentives; and we also r
eport on the effects of incentives on response quality, sample composition,
response bias, interviewer and respondent expectations, and costs.