Krishnamoorthy Kalimuthu, Mathew Thomas
Department of Mathematics, University of Louisiana, Lafayette, 70508, USA.
Ann Occup Hyg. 2013 Aug;57(7):953-61. doi: 10.1093/annhyg/met005. Epub 2013 Mar 2.
The symmetric-range accuracy A of a sampler is defined as the fractional range, symmetric about the true concentration, that includes a specified proportion of sampler measurements. In this article, we give an explicit expression for A assuming that the sampler measurements follow a one-way random model so as to capture different components of variability, for example, variabilities among and within different laboratories or variabilities among and within exposed workers. We derive an upper confidence limit for A based on the concept of a 'generalized confidence interval'. A convenient approximation is also provided for computing the upper confidence limit. Both balanced and unbalanced data situations are investigated. Monte Carlo evaluation indicates that the proposed upper confidence limit is satisfactory even for small samples. The statistical procedures are illustrated using an example.
采样器的对称范围精度A被定义为围绕真实浓度对称的分数范围，该范围包含指定比例的采样器测量值。在本文中，我们给出了A的显式表达式，假设采样器测量值遵循单向随机模型，以便捕捉不同的变异性成分，例如，不同实验室之间和内部的变异性，或暴露工人之间和内部的变异性。我们基于“广义置信区间”的概念推导出A的上置信限。还提供了一个方便的近似值来计算上置信限。研究了平衡和不平衡数据情况。蒙特卡罗评估表明，即使对于小样本，所提出的上置信限也是令人满意的。通过一个例子说明了统计程序。
