The role of question format for the support for national climate change mitigation policies in Germany and the determinants of WTP

- We estimate WTP for decreasing GHG emissions under different question formats.
- Mean WTP in the standard DC format is double the WTP in a two-way-payment ladder.
- Median WTP does not vary with question format.
- This finding suggests that differing response incentives do not affect median WTP.

This contingent valuation survey examines the willingness to pay (WTP) for climate change mitigation in Germany. Willingness to pay is assessed by using a classic dichotomous choice referendum format and a two-way payment ladder in a split-sample design. We find that mean WTP under the referendum format is more than twice the WTP in the payment ladder format, but median WTP does not differ. Moreover, we test the possible effect of different determinants on WTP. Determinants that considerably influence WTP are personal norm, climate change scepticism, agreement with the German Renewable Energy Law and individualistic cognition. Income and gender are also important predictors.