把完备信息系统、不完备信息系统、序信息系统、覆盖信息系统等常见信息系统统称为广义信息系统,采用新的知识表达形式将其知识结构进行统一表示,特别是将覆盖信息系统纳入了广义信息系统的框架之中。在广义信息系统中引入粒度熵的概念,对属性的重要性给出度量;在此基础上,提出一种广义信息系统属性约简的启发式算法,进而得到广义信息系统的知识约简,并给出了若干算例。
In this paper,complete information system,incomplete information system,ordered information system and covering information system are viewed as a generalized information system,and its knowledge structures are uniformly represented by a new knowledge expressing form.In particular,the covering information system becomes its special form.By estimating the granular entropy of generalized information system,the significance of attribute is defined.Furthermore,a heuristic algorithm of attribute reduction in generalized information systems is proposed,and some test examples are given.