Survey incentives: When offering nothing is better than offering something

Why do people take the time to respond to surveys in Georgia? A telephone survey experiment CRRC-Georgia carried out in May 2017 suggests that small financial incentives may actually discourage people from participating in surveys. This finding suggests people may respond to surveys for intrinsic (e.g. because they are curious or want to help) rather than extrinsic reasons (e.g. doing something for the money).

During the experiment, 2320 respondents were asked whether they would be willing to participate in future phone surveys. Half were offered a GEL 2 transfer (about US$0.82 at the time of the survey) to their telephone in exchange for doing so. The other half was not offered any incentive. Respondents were randomly assigned whether they were offered an incentive or not.

The difference in responses isn’t impressive, but is statistically significant. Approximately 4% fewer people said they would participate in future surveys when offered the incentive. The chart below displays the effects of different variables on willingness to participate in future surveys in terms of odds ratios. The first model looks at the effect of being offered GEL 2 alone, while the second model controls for age, sex, and settlement type. The odds of someone responding positively when offered the incentive where approximately 0.8 to 1 in both regressions, meaning that the offer made it less likely that individuals would be willing to participate in a future survey. The second model also shows that except for those in the 36-55 age group, demographic characteristics have no effect on people’s likelihood of agreeing to participate in future surveys.


Note: For the regression models presented above, “No” was coded as the base category, “Don’t know” as the second category, and “Yes” as the third category. The logic behind coding “Don’t know” as a middle category is that the person is not refusing to participate in future surveys, but rather is saying they might or might not. 

The results of this experiment show that people in Georgia are slightly less likely to want to participate in future surveys if you offer them a small amount of money compared with offering nothing. This finding may at first seem strange. However, a potential explanation is that GEL 2 may have seemed like a paltry sum, and people may have been offended. In turn, rather than engaging people’s intrinsic motivations like a sense of duty to help others or simple curiosity, the offer of GEL 2 could have activated people’s extrinsic motivations. In turn, the extrinsic incentive wasn’t large enough to counter the loss in the intrinsic value of participation, at least on average.

For a look at a comparable effect in a very different context, this study on attitudes towards having nuclear waste facilities found a similar pattern: when offered money, people were less likely to support having such a facility in their community.

Have other thoughts on what might have encouraged those offered GEL 2 to participate in future surveys to decline participation more frequently? Let’s have a conversation on Facebook or Twitter.