Turnbull Nonparametric Estimator for Williness to Pay
turnbull {bid} {t}
where
bid is the variable that reports the bid value offered to the respondent.
t is the variable that indicates if the repondent would like to contribute to the project at the price offered (T =1 if WTP>AMOUNT).
Description
turnbull estimates the Turnbull empirical distribution estimator of willingness to pay proposed by Carson et al (1994a,b). Haab and McConnell (1997) argue that this estimator solves the problem of estimating negative willingness to pay without resorting to ad hoc distribution assumptions, and show that central tendency measures of willingness to pay from parametric models are sensitive to the assumed distribution, while the lower bound Turnbull estimate is robust accross distributions.
Examples:
. use ferry dataset (http://www-sekon.slu.se/~bkr/) . turnbull bid t . turnbull bid t, short
Reference
Azevedo, Joao Pedro. What is the Value of Educational Broadcast? (February 2009). Available at SSRN: http://ssrn.com/abstract=1332786.
Carson, R. T., W. M. Hanemann, R. J. Kopp, J. A. Krosnick, R. C. Mitchell, S. Presser, P. A. Ruud, and V. K. Smith (1994a) ‘‘Prospective Interim Lost Use Value Due to DDT and PCB Contamination in the Southern California Bight,’’ NOAA Contract No.-DGNC-1-00007.
Carson, R. T., L. Wilks, and D. Imber (1994b). Valuing the preservation of Australia’s Kakadu Conservation Zone, Oxford Econom. Papers 46, 727-749.
Haab, T. and K. McConnell (1997). Referendum Models and Negative Willingness to Pay: Alternative Solutions. Journal of Environmental Economics and Management 32(2), 251-270.
Authors
Joao Pedro Azevedo jazevedo@worldbank.org
Also see
spike if installed.