与生产过程能力验收流程相似,测量过程能力验收包括测量设备能力验收→测量过程能力验收→监控测量过程的稳定性。本文将介绍监视测量过程的稳定性,同时也给大家介绍与偏倚相关的三个概念——偏倚、线性、稳定性!
一、偏倚、线性、稳定性定义
偏倚、线性、稳定性是都跟偏倚相关的一组概念,线性是量程上的偏倚,稳定性是时间上的偏倚:
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551256280260707.jpg)
二、偏倚
首先,我们了解偏倚的概念,偏倚采用假设检验法进行研究,研究方法如下:
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551314619019705.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551320856304472.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551326891021896.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551332271796944.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551339613820706.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551345374754672.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551351773095262.jpg)
总结:按如上的方法分析,如果统计的t值位于95%置信区间内,说明偏倚可接受;如果不位于置信区间内,说明偏倚不可接受,须调零。
三、线性
线性计算比较复杂,可以按如下步骤借助统计工具辅助进行线性分析:
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551422139091348.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551433740102936.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551439395425363.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551448274032891.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551456963005050.jpg)
采用Minitab如下功能辅助功能进行线性分析:
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551503612917401.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551510142594525.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551515887939993.jpg)
四、稳定性
稳定性分析类似于生产用控制图,参考如下方法实施:
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551650260966048.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551656211836688.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551661896372136.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551667055763159.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551672749629552.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551677981464179.jpg)
![](http://static.quality-in.com/upload/eduplat/article/20170801/1501551683190849196.jpg)