Ahlheim, Michael; Börger, Tobias; Frör, Oliver - In: Journal of Environmental Economics and Policy 2 (2013) 1, pp. 45-70
In contingent valuation studies to assess the economic value of environmental goods, respondents are often given small presents or money amounts at the beginning of the interview to compensate them for their time spent on the survey and to encourage them to be conscientious when answering the...