Offering incentives seems like a great idea to stimulate participation in a survey. You can offer people a discount or a voucher for completing the survey. But all is not what it seems.
Eleanor Singer in her 2002* book discovered that direct incentives encourage participation in proportion to the size of the incentive offered. Larger incentives will give larger response rates. Money is more effective than vouchers or gifts. Prize draws are less effective than ‘payments’.
There is also a risk that incentives may result in more positive responses. Respondents are getting something for free, so it artificially increases their ...