摘要 : This paper reports results from a U.S. national telephone survey on genetically modified foods (vegetable oil, cornflakes, and salmon). The survey featured a contingent valuation in which respondents chose between the GM and non-G... 展开 This paper reports results from a U.S. national telephone survey on genetically modified foods (vegetable oil, cornflakes, and salmon). The survey featured a contingent valuation in which respondents chose between the GM and non-GM alternatives with an option of indifference. The binomial and multinomial logit models yielded estimated willingness to pay (WTP) to avoid the GM alternatives. Respondents were willing to pay 20.9%, 14.8%, 28.4%, and 29.7% of the base prices to avoid GM vegetable oil, GM cornflakes, GM-fed salmon, and GM salmon, respectively. The inclusion of indifference option could increase the sample size and moderate the mean WTP. 收起