A fuzzy expert system for contract decision making

Abstract

A fuzzy reasoning model is constructed and its application to contract decision making in Hong Kong is illustrated. According to professional experience, six inputs are identified as essential factors determining contract choice. They are the scale of the project, the nature of the works to be carried out, the characteristics of the client, the time constraint, the source of materials for construction and the characteristics of the building design. These factors determine whether the contract to be chosen should be in the form of a simple quotation, a lump sum contract on drawings and specifications, a schedule of rates, a management contract, a lump sum contract in standard form without quantities or one with quantities. Ten decision rules are constructed based on expert opinions. Two practical cases are investigated and presented to illustrate how the method works.