一、关于测量不确定度的评定方法测量不确定度的评定方法有且只有两种,即A类和B类,这种分类对评定结果来说不存在本质上的区别,在实际评定中并不一定两种方法都要使用,采用哪一种方法取决于评定信息来源的方便与可靠。A类评定方法中经常使用的是贝塞尔公式,这种方法大家经常使用,比较熟悉,这里不作过多赘述,这里重点谈谈A类评定中的极差法。采用极差法评定有一个前提条件是重复观测结果的分布是正态分布或接近正态 First, the measurement uncertainty on the measurement method Measurement uncertainty measurement methods and there are only two, namely, A and B, this classification does not exist on the assessment results of the essential differences in the actual assessment and It is not always necessary to use either method, and the method used depends on the convenience and reliability of the source of the information being assessed. Category A method is commonly used in the Bessel formula, this method we often use, more familiar, not to go into details here, the focus here to talk about the A-class assessment of the very poor method. There is a prerequisite for the use of range method assessment is the distribution of repeated observations are normal or near normal distribution