可变精度优势关系下的析取集值有序信息系统

Disjunctive Set-valued Ordered Information Systems Based on Variable Precision Dominance Relation

集值信息系统是单值信息系统的一种推广,按照语义可划分为合取集值信息系统和析取集值信息系统两类。本文分析了析取集值信息系统中已有的4种优势关系的局限性,提出了一种可变精度优势关系,定义了可变精度优势关系下的析取集值有序信息系统,扩展了经典粗糙集理论。然后,在析取集值有序信息系统中引入了一种对象排序的新方法,该方法利用对象在信息系统中的整体优势度来对对象进行排序。最后,通过风险投资实例说明本文方法可以用于处理析取集值有序信息系统中的决策规则获取问题。

Set-valued information systems are generalized models of single-valued information systems. It could be divided into two categories ：conjunctive and disjunctive set-valued information systems. Through analyzing the limitations of four existing dominance relations in disjunctive set-valued information systems,a novel variable precision dominance relation is proposed and a disjunctive set-valued ordered information system based on variable precision dominance relation is defined. It is an extension of the classical rough set theory. Then ,an approach for sorting objects is introduced to the disjunctive set-valued ordered information systems ,which is based on the whole dominance degree of an object in an information system. Finally,a case of a venture investment proved it to be a valid approach for extracting decision rules from disjunctive set-valued ordered information systems.