The Reliability of Delphi Surveys and Benefit Transfer to Predict Outcomes of Contingent Valuation Surveys

Benefit transfer (BT) and valua-tion experts'assessments in Delphi contingent valuation (CV) surveys have been used as an alternative to prohibitively expensive world-wide CV surveys to obtain estimates of total nonuse values of global public goods. We test the reliability of international BT and Delphi CV estimates by comparing them to a popu-lation CV survey of Norwegian households' willingness to pay (WTP) for Amazon rainfor-est preservation plans. The Delphi CV method predicts WTP and scope effects in line with conventional BT, motivating further testing of the Delphi CV method as a time-and cost -saving way of valuing global public goods.