Contingent valuation with an open‐ended follow‐up question: a test of scope effects
研究在二分式条件估值问题后添加开放式后续问题是否对评估商品的范围敏感，结果未发现显著范围效应，不支持在条件估值中使用开放式后续问题。
It has been suggested that an open-ended follow-up question should be added to the binary contingent valuation question. Before this is generally recommended, it is important to evaluate the properties of such follow-up questions. Using a split sample approach, we test whether the open-ended follow-up is sensitive to the scope of the commodity being valued. No significant scope effects were detected. It is concluded that the results obtained do not support the use of an open-ended follow-up in contingent valuation applications. © 1997 John Wiley & Sons, Ltd.