Why win-wins are rare in complex environmental management

Margaret Hegwood and Matthew G. Burgess, Environmental Studies Program, University of Colorado Boulder, Boulder, CO, Ryan E. Langendorf, Cooperative Institute for Research in Environmental Sciences, Boulder, CO

Background/Question/Methods
High-profile modeling studies often project that large-scale win-win solutions exist in environmental management, either improving aggregate objectives such as economic gains and conservation, or improving outcomes for multiple stakeholder groups. However, on-the-ground scholars and managers often approach win-win narratives skeptically, due to real-world complexity. Case-study meta-analyses also find win-wins are relatively rare. We show mathematically why complexity reduces the availability of win-wins. We also characterize two-dimensional tradeoffs with a meta-analysis, and show how to extrapolate results of two-dimensional studies to higher dimensional realities.
Results/Conclusions
We provide a general proof that, under uncertainty, the probability a manager should assign to win-win outcomes existing (here meaning Pareto improvements) strictly decreases in: the number of objectives, the number of stakeholders, and the number of constraints. We show that the maximum fraction of single-objective best outcomes simultaneously achievable for all objectives, a measure of tradeoff severity, also decreases (i.e. tradeoff severity increases) in the number of objectives, and approaches a limit unaffected by tradeoff surface curvature. This is important because our meta-analysis shows that most (77%) of empirically estimated two-dimensional tradeoff surfaces are concave. Concave tradeoffs are less severe, and moreso in lower dimensions. Our model can extrapolate these estimated low-dimensional tradeoff severities to arbitrary higher dimensions. This work provides precise intuition and quantitative guidance for interpreting implications of simple tradeoff studies for complex realities.