Monster Seminar JAM - A Decision Support System for Analyzing Stock Status: Quantifying ''maybe''
Dr. Pete Lawson
Conservation Biology Division, Northwest Fisheries Science Center - Newport
Technical Recovery Teams (TRTs) have the task of assessing the biologicalstatus of populations and ESUs. The task involves bringing together disparate data sets from many populations and rolling them up into an ESU assessment. Assessments must be completed in the face of uncertainty about the true state of a system as well as the desired state. Decision support systems (DSS) are, broadly, interactive computer-based systems that help decision makers utilize data and models to solve problems. DSSs usually include (1) a user interface, (2) a data base, (3) models and analytical tools, and (4) DSS architechture and network. Fuzzy logic is an extention of Boolean logic that allows for partial truth. It replaces the binary true or false with truth values representing degrees of truth. These truth values incorporate an expression of uncertainty. I describe a DSS that includes a network of factors evaluated with a fuzzy logic knowledge base to evaluate the degree of truth of three statements: (1) the ESU is persistent, (2) the ESU is sustainable, and (3) the ESU is recovered. The DSS provides a structure to summarize messy data sets, explicitly describe the analysis framework, and document the process. The use of fuzzy logic changes the focus of criterion development away from thresholds and toward ranges that express degrees of certainty in functional relationships as well as input data quality and quantity. This DSS structure has also been used to evaluate critical habitat and is being adapted to analyze limiting factors. It serves decision makers by providing an assessment that incorporates uncertainty and can be used in conjuction with outside information to arrive at an informed management decision.
Date and Time:
December 8, 2005,
11:00 am - 12:30 pm