References
- Blumenschein , K. , Blomquist , G. C. , Johannesson , M. , Horn , N. and Freeman , P. R. 2008 . Eliciting willingness to pay without bias: evidence from a field experiment . The Economic Journal , 118 : 114 – 37 .
- Farmer , M. C. and Lipscomb , C. A. 2008 . Conservative dichotomous choice responses in the active policy setting: DC rejections below WTP . Environmental and Resource Economics , 39 : 223 – 46 .
- Johansson , P. -O. 1995 . Evaluating Health Risks: An Economic Approach , Cambridge : Cambridge University Press .