Web surveys are becoming quite popular, but researchers are still trying to determine effective methods to improve response rates to web surveys. Compared to mail and telephone surveys, there are relatively few studies of incentives using web surveys. This study investigates the degree to which the economic exchange theory versus the social exchange theory can explain web survey participation. This study presents the results of an experiment that varied the disbursement of a $20 incentive in a two-wave panel study (January, March 2010, n=350). In one condition, participants are given a $10 pre-paid incentive during wave 1, which is followed by a $10 postpayment after wave 2. In another condition, participants are given a $5 incentive during wave 1, which is followed by a $15 post-payment after wave 2. If the economic exchange theory explains survey participation, I would expect to find that response rates at wave 1 are higher for the $10 incentive group than the $5 incentive group. Furthermore, I would expect to find that the $5+15 group would participate at a higher rate than the $10+10 group in wave 2, because the balance of the reward is greater ($15 versus $10). If the social exchange theory explains survey participation, I would expect to find no differences between the two groups in terms of their response rates to both waves of the survey. Furthermore, using wave 1 survey responses about trust, volunteering, and civic ethic, I examine whether the different incentives recruited different types of people during wave 1 and whether these survey responses could be used to predict participation during wave 2.

The findings from this study will help determine effective ways to disburse incentives in a panel design, determine the optimal size of incentives, and understand the motivation for participating in web surveys.