Abstract: ariable precision rough set model is the extension of standard Rough Set model.Through introducing a parameter-β,the ability of adapting noisy data has been improved.This paper analyzes the relationship of classification quality-γ and parameter-β in decision tables,and constructs an algorithm to ascertain the β area based on given γ value.

Key words: variable precision rough set, parameter-β, quality of classification（γ）, threshold value

摘要： 可变精度粗糙集模型是标准粗糙集模型的扩展,通过引入参数β,改善了粗糙集模型对噪声数据的适应能力。通过对VPRS理论的应用,分析了决策表中分类质量γ与参数β值之间的反向相关关系,基于两者之间关系的分析结果,给出了依据γ来确定β精确取值区间的算法。

关键词: 可变精度粗糙集, 参数-β, 分类质量, 阀值