Abstract
Analyses using a logical hierarchical model, such as Evidential Support Logic, are useful tools to assess complicated hydrogeological and groundwater conditions in decision making. However, in most cases, parameters in the model are not determined explicitly, which prevents more objective evaluation. In this study, in order to identify weight parameters between propositions in different layers in a hierarchical model, a method to calculate the parameters based on distribution of many people's opinion was proposed. An example of hierarchical model for logic structure to evaluate risk of groundwater environment change under a hypothetical condition was developed, and some of the weight parameters were calculated by using Genetic Algorithm with distribution data of opinions collected through questionnaires.
