Comparisons of Risk-based Decision Rules for the Application of Water Resources Planning and Management

Water resources planning and management are plagued with various uncertainties in that any chosen management alternative always has the possibility to be inferior to other competing alternatives. To facilitate risk-based decision making, the minimax expected opportunity loss (EOL) rule is applied for alternative selection. Two existing risk measures as well as EOL are compared and their implications in risk-based decision making are examined. It is shown that EOL can reflect more accurately the relative merit of two competing alternatives without suffering the pessimism and the counter-intuition of the other two risk measures considered herein. The minimax EOL rule is demonstrated through an application to a river basin management decision for improving the navigation. The results show that the correlation between outcomes of competing alternatives and decision maker's acceptable risk are important in decision making under uncertainty.