Taxonomy, Structure, and Implementation of Evidential Reasoning

Evidential reasoning refers to inference mechanisms by which the evidence provided by a set of indicators is analyzed in order to gain better understanding of a given hypothesis, concept, situation, or phenomenon. Problem solving tasks of this nature include, for instance, medical diagnosis, , weather forecasting, corporate assessment, political crisis assessment, and battlefield reading. All of these problems share common characteristics in that the problem solver starts with an initial incomplete understanding of the situation (e. g. patient status> and based on his prior knowledge and expectations, he then looks for additional information that may reduce the uncertainty regarding the complete picture of the situation. Following a cyclic process, sources for additional information are identified, evaluated, and utilized, the new evidence is integrated into the existing knowledge base, the situation is reassessed and, if final assessments cannot be made, further information is requested. The process ends when the problem solver decides that he knows enough to form a