Valuation is one of the key tools used by environmental economists to inform decision making on crucial issues such as habitat conservation and land-use planning. By calculating how much a resource is worth, researchers can give advice on the economic benefits of conserving it or calculate damage claims or compensation if it is destroyed. However, despite valuation's importance and widespread use, a new study has shown the need for the re-appraisal of some of its underlying assumptions and concepts, especially when it comes to non-marketed goods & services. The study investigated the value of tropical rainforest - a resource which provides benefits that are global, national and local in nature. To do this, the study compared the willingness of people in PNG and America to pay for tropical forest conservation and investigated what underlying factors affected their responses. He found that there were significant differences in the values obtained in the two countries. This study also found that non-economic values - due, for example, to ethical, moral and social factors - were a major factor motivating people's willingness to pay for forest conservation. The study concluded that his findings throw doubt onto the advisability of transferring valuations between study areas - particularly between developed and developing countries - and that definitions of what constitutes 'value' and 'willingness to pay' need to be tightened if inaccurate value estimates are to be avoided.
