A nonparametric welfare analysis on water quality improvement of the floating people on Inlay Lake via a randomized conjoint field experiment

This study evaluates the potential surplus gain of a water improvement policy and the causal effects of its components on choice probabilities for the floating people on Inlay Lake, Myanmar, based on a randomized conjoint field experiment. In our experimental design, respondents rank three options: two alternative policies and one status quo. We then present a method that enables us to estimate the minimum willingness-to-pay for a policy in the form of compensating variations under a set of weak assumptions using this conjoint data. Results show inter alia that the provision of toilet facilities and a collective wastewater treatment, and joint implementation of the policy by the government and local NGOs have a positive effects on the choice probabilities. Results also show that the surplus gain from a water-quality improvement policy is at least as large as 22.9% of the average annual per-capita income of those on the lake.