Nonmonotonic model inference: A formalization of student modeling

A student model description language and its synthesis method are presented. The language called SMDL is based on a logic programming language taking 4 truth values such as true, false, unknown and fail. A modeling method called HSMIS is a new nonmonotonic model inference system and has the following major characteristics: (1) Model inference of logic program taking 4 truth values, (2)Treatment of nonmonotonicity of both student's belief and inference process itself. HSMIS incorporates de Kleer's ATMS as a vehicle for formulating the nonmonotonicity. Both SMDL interpreter and HSMIS have been implemented in Common ESP(Extended Self-contained Prolog) and incorporated into a framework for ITS, calle