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Web Survey Bibliography

Title Effectiveness of incentives in mixed-mode systems: An evaluation of errors & costs
Year 2009
Access date 29.10.2009

Declining response rates force survey researchers to implement surveying strategies that would motivate target persons to cooperate. Incentives have often proved to be a viable approach to address this issue. They have been increasingly used also in web surveys, which are relatively cheaper, compared to other modes but at the same time su er from generally lower response rates. Since the problems like noncoverage and lack of sampling frames still make web surveys largely inappropriate for surveying general populations, the possibility of their integration into mixed-mode designs has become one of the central questions of survey methodology. This introduced a new area also for methodological research on incentives.

While incentives can substantially increase response rates, they can also signi cantly heighten the research costs. Furthermore, the impact on survey responses often remains uncontrolled and is largely unclear in mixed-mode designs. In this paper, we study the problem of using incentives in mixed-mode surveys of the general population by comparing response rates, errors and costs among di erent experimental mixed-mode designs.

The experiment was conducted on a sample of the general Slovene population. Participants were randomly assigned into one of experimental groups, manipulating two di erent combinations of modes (web/mail and web/telephone) and three di erent types of incentives (no incentive, wallet as a gift and 5 Euros in cash). We first present the impact of incentives on response rates in each of the groups and compare errors using the Mean Square Error approach. The results show that the response rates are not a good predictor of the data quality, since the monetary incentives signi cantly boosted cooperation but at the same time produced a high bias. This finding is then elaborated by a detailed analysis of the response patterns that might have contributed to the bias. Possible adjustments of survey design, that may provide a higher data quality, are discussed as well. Finally, the cost aspects are taken into account and evaluated by a simulation of di erent initial sample sizes and their e ffect on the costs-errors optimization. The ndings of the study suggest that the use of incentives in mixed-mode surveys should be methodologically well elaborated, not only from the aspect of response rates, but also with a careful consideration of survey errors and costs.

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Year of publication2009
Bibliographic typeConferences, workshops, tutorials, presentations

Web survey bibliography - Slovenia (127)