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K.L. Giraud

Publications and source records attributed to K.L. Giraud.

2 recordsLinked to original sources

Internal and external scope in willingness-to-pay estimates for threatened and endangered wildlife

Economic theory suggests willingness-to-pay (WTP) should be significantly higher for a comprehensive good than for a subset of that good. We tested this using both a split sample design (external scope test) and paired responses (internal scope test) for WTP for several endangered fish and wildlife species in the US. In the paired response case we corrected for correlation of willingness-to-pay responses using a bivariate probit model. Surprisingly, the independent split samples passed the scope test but the paired samples did not. As the results contradict each other, questions of validity for policy implications are raised. However, using either approach, the benefit of maintaining critical habitat for these species exceeds the costs.

Journal of Environmental Management↗

Two valuation questions in one survey: Is it a recipe for sequencing and instrument context effects?

Economic theory suggests that willingness to pay for two goods independently offered should remain unchanged when the survey instrument changes slightly. Four survey treatments consisting of comprehensive good and a subset of that good were used. The surveys alternated in the question ordering and in the embedded good which accompanied the comprehensive good. We tested for sequencing and instrument context effects using both a combined and split sample designs. In the combined sample case we found some evidence to sequencing effects in the data containing the first subset good. Likelihood ratio tests indicated that sequencing did not effect scale or location of parameters. In the test for instrument context effects, evidence was found indicating context does effect willingness to pay estimates.

Applied Economics↗