摘要：This paper considers the treatment of "don't know" (DK) responses to referendum contingent valuation questions. The determinants of DK responses are empirically analyzed using a data set from a survey of old growth forest valuation. It is found that DK respondents possess unique characteristics that differentiate them from Yes and No respondents. These findings do not support the most common treatments of DK responses that are currently used. Responses to an open-ended question included in the survey are used to provide further insight into the preferences of DK respondents.
