The effect of giving respondents time to think in a choice experiment: a conditional cash transfer programme in South Africa

We conducted a choice experiment (CE) to estimate willingness to accept (WTA) values for a planned conditional cash transfer (CCT) programme designed to increase toilet use in South Africa. The payment is made conditional on using a toilet and bringing urine to a central collection point. In a split-sample approach, a segment of respondents were given time to think (TTT) (24 hours) about their responses, while the remaining respondents had to answer immediately. We found significant differences in the choice behaviour between the subsamples. To validate the stated preferences with actual behaviour, a CCT programme was implemented afterwards. The stated WTA estimates were far below those revealed by actual behaviour for both subsamples. The authors would like to thank Marcella Veronesi and two anonymous reviewers for their valuable comments, the eThekwini Municipality for their logistical support, and all of the enumerators. They are grateful for the financial support of the Bill and Melinda Gates Foundation (Grant #OPP1011603). The funding source had no involvement in any aspect of the research or preparation of the article. use, available at https:/www.cambridge.org/core/terms. https://doi.org/10.1017/S1355770X16000280 Downloaded from https:/www.cambridge.org/core. IP address: 54.191.125.211, on 16 Jan 2017 at 04:27:07, subject to the Cambridge Core terms of 2 Elizabeth Tilley et al. Contrary to our expectations, the TTT group had underestimated their actual WTA values by an even larger margin. The preferences for various attributes were nevertheless useful in informing the design of the real intervention.