Against a backdrop of increasing species imperilment, there is considerable empirical evidence that preserving threatened, endangered, and rare (TER) species provides significant economic benefits to society. But efforts to measure these benefits has generated both strong methodological and philosophical criticisms. Since the 1960s, economists have developed a battery of nonmarket valuation approaches for estimating economic values associated with changes in the quantity or quality of environmental goods and services. This battery includes both revealed preference and stated preference (SP) approaches (including the contingent valuation [CV] method), with only the latter capable of providing willingness to pay (WTP) estimates for nonuse values. The total economic value of TER species preservation can include nonconsumptive use values (e.g., wildlife watching), and may be especially composed of nonuse values (e.g., based on existence value motivations).
By the early 1980s, applied CV studies focusing on TER species preservation had begun to accumulate. Early research centered in the United States. By the mid-1990s the first statistical meta-analysis of TER species NMV studies was completed, and was then updated a dozen years later. These metaregression functions facilitated potential benefit transfers, where the systematic structure of prior original studies could be used to estimate WTP values for a TER species in another setting (absent an original study). Since roughly 2010, the use of choice experiments as an alternative SP approach expanded rapidly. Likewise, the accumulation of additional SP studies generated new summary reviews and meta-analyses, including applications from both developed and developing countries, and expanded benefit transfer opportunities. Going forward, new studies will lead to updated meta-analyses, with additional statistical and theoretical sophistication. Critiques targeted to SP approaches (e.g., with respect to hypothetical bias and nonuse value motivations) will likely remain, and further validity testing and methods development are called for. However, from a pragmatic perspective, persistent efforts at quantification continue to help make the benefits of TER species preservation visible in the face of rapidly increasing species imperilment.
A COMPARATIVE EXPECTED VALUE ANALYSIS STUDY TO DETERMINE IF THE ECONOMIC BENEFITS OF THE MOST COMMONLY PRESCRIBED PRESCRIPTION AND NON-PRESCRIPTION DRUGS IN THE UNITED STATES PROVIDE ECONOMIC VALUE
