Dempster-Shafer Reasoning For TheBiological Surveillance Of River Water Quality
Michael Boyd, William J. Walley, H.A. Hawkes · WIT transactions on ecology and the environment · 1970
An application of Dempster-Shafer reasoning for the biological surveillance of river water quality is described. A reasoning system is being developed which emulates the expert's ability to determine the quality of river water from samples of benthic macro-invertebrate communities taken from the river bed. Diagnoses of river water quality are reported in terms of a proposed biological classification scheme. Ecological knowledge on a reference set of indicator organisms is stored in the form of subjective probability distributions, representing the occurrence of the organisms in each of four discrete states of abundance across the quality classes. These distributions provide support for competing propositions in the frame of discernment formed by the biological classes. Combination of this support leads to a classification of river water quality at a sampled site. The reasoning system has been tested in its ability to match the expert's classification of a set of 53 sampled river sites. The results suggest that Dempster-Shafer reasoning affords a viable procedure for integrating biological evidence in order to classify river water quality.