行式存储的快速属性约简算法

Fast Attribute Reduction Algorithm Based on Row Storage

现有属性约简算法主要针对数据全部驻留内存的情况.为减少访问磁盘的I/O次数,文中提出一种行式存储方式,无需数据全部驻留内存.约简时将同类子划分收集到一个数组中,可快速得到简化决策表.同时引入不可区分率定义作为衡量属性重要性的依据,进而提出一种快速的属性约简算法,其时间复杂度和空间复杂度较低.通过实例和实验验证文中算法的有效性、可行性.

The existing attribute reduction algorithms mainly focus on the area of resident data in the memory. To decrease the accessing disk I/O times, a row storage mode is proposed. In this mode, not all data are required storing in the main memory. During the reducing process, the sub divisions of same category are collected into one array to get the simplified decision table quickly. Meanwhile, the indiscernibility degree is introduced as the measurement of the attribute importance. Then, a fast attribute reduction algorithm is proposed. Its time complexity and space complexity are low. The examples and experimental results show the effectiveness and feasibility of the proposed algorithm.