anchor: For example, suppose a study estimates that the average WTP for a reduction in mortality risk of 1/100,000 is $50, but that the actual mortality risk reduction resulting from a given pollutant reduction is 1/10,000.
positive: If could be estimated that a reduction in mortality risk of 1/100,000 is $50, but the actual reduction may vary.
negative: Studies can always accurately estimate reductions in mortality rates.