Forming a comparison reference value from different distributions of belief
Forming a comparison reference value from different distributions of belief
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DOI：
10.1088/0026-1394/43/1/002
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发表时间：
2006-02-01
期刊：
影响因子：
2.4
通讯作者：
Willink, R
中科院分区：
文献类型：
--
作者：
Willink, R
如果测量不确定度是通过形成被测变量的置信度分布来表示的，那么这应该反映在实验室间比较数据分析的理论基础中。本文提出了一种相应的方法，用于计算比较中的参考值，其中每个实验室独立地将概率密度函数f（i）（x）分配给稳定伪影的值X。简单的论证表明，X的共识密度函数可以取为f（x）= Pi（n）（i=1）f（i）（x）/ f Pi（n）（i=1）f（i）（x）dx，假设n个实验室的密度是可靠的和相互一致的。还提出了一种方法来检查这种一致性。结果f（x）是统计文献中共识的一个特例，称为对数意见池。关键比较参考值可以取为f（x）的均值、中位数或众数。所开发的方法不明确涉及实验室偏倚（偏移），这是最近发表的大多数比较分析方法的重要特征，与等效度的计算有关。当假设存在这种抵消时，信念方法似乎不太适合。
If measurement uncertainty is to be expressed by forming a distribution of belief for the measurand then this should be reflected in the theory underlying the analysis of interlaboratory comparison data. This paper presents a corresponding method for the calculation of a reference value in a comparison where each laboratory independently assigns a probability density function, f(i) (x), to the value X of a stable artefact. Straightforward argument shows that a consensus density function for X can be taken as f(x) = Pi(n)(i=1) f(i)(x) / f Pi(n)(i=1) f(i)(x) dx, assuming that the densities of the n laboratories are reliable and mutually consistent. A method is also presented for examining this consistency. The result f (x) is a special case of a consensus in the statistical literature called the logarithmic opinion pool. The key comparison reference value might be taken as the mean, median or mode of f(x).The method developed does not explicitly involve laboratory biases (offsets), which are important features of most methods for comparison analysis published recently and which are relevant to the calculation of degrees of equivalence. The belief approach does not seem well-suited when it is assumed that such offsets exist.