1.1 本规程规定了对无损检测（NDT）进行统计分析的程序 â 对 一 用于确定特定检查参数集的证明检测概率（POD）的数据。涵盖的主题包括标准 â 对 一 回归方法、POD曲线公式、验证技术和结果的正确解释。 1.2 单位- 以英寸-磅为单位的数值应视为标准值。括号中给出的值是到国际单位制的数学转换，仅供参考，不被视为标准值。 1.3 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 本文描述的POD分析方法基于众所周知和公认的统计方法。它应用于在以下条件下，对一组特定的检查参数和已知的不连续尺寸范围进行量化。 5.1.1 无损评估检测系统的初始响应是可测量的，可以归类为连续变量。 5.1.2 不连续尺寸是预测变量，可以精确量化。 5.1.3 不连续尺寸之间的关系( 一 )和测量的信号响应( â )存在并最好由具有误差结构的线性回归模型描述，该误差结构为正态分布，具有均值零和常数方差σ 2. . （注意，在线性回归中，“线性”是指相对于模型系数的线性。尽管是二次模型 绘制时不具有线性形状，例如，它在回归分析中被归类为线性模型，因为它相对于模型系数是线性的。 ) 5.2 这种做法不限制使用具有多个预测变量的线性回归模型或其他统计模型，如果证明更适合 â 对 一 数据 5.3 这种做法不适用于非破坏性评估系统上的POD检查产生的数据，该系统会产生二进制性质的初始响应（例如，命中/未命中）。实践 E2862年 适用于产生命中/未命中类型响应的系统（例如，荧光渗透剂）。 5.4 在进行分析之前，假设明确定义了兴趣的不连续性；POD样本集中诱导不连续尺寸的数量和分布是已知的，并有充分的记录；POD检查管理程序（包括数据收集方法）设计良好、定义明确、可控且无偏见（见 X1.2.2 更多细节）；初始检查系统响应在本质上是可测量和连续的； 检验系统已校准；测量误差已经过评估，认为可以接受。只有在以下情况下，分析结果才有效: â 对 一 数据准确且精确，线性模型充分代表了 â 对 一 数据 5.5 本文描述的POD分析方法与以下分析方法一致: â 对 一 MIL-HDBK-1823A中描述的数据，包括在几个广泛使用的POD软件包中，用于对进行POD分析 â 对 一 数据它也存在于具有线性回归分析能力的统计软件包中。这种做法要求分析员可以使用POD软件或具有线性回归分析能力的其他软件。

1.1 This practice defines the procedure for performing a statistical analysis on Nondestructive Testing (NDT) â versus a data to determine the demonstrated probability of detection (POD) for a specific set of examination parameters. Topics covered include the standard â versus a regression methodology, POD curve formulation, validation techniques, and correct interpretation of results. 1.2 Units— The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 The POD analysis method described herein is based on well-known and well-established statistical methods. It shall be used to quantify the demonstrated POD for a specific set of examination parameters and known range of discontinuity sizes under the following conditions. 5.1.1 The initial response from a nondestructive evaluation inspection system is measurable and can be classified as a continuous variable. 5.1.2 Discontinuity size is the predictor variable and can be accurately quantified. 5.1.3 The relationship between discontinuity size ( a ) and measured signal response ( â ) exists and is best described by a linear regression model with an error structure that is normally distributed with mean zero and constant variance, σ 2 . (Note that in linear regression, “linear” means linear with respect to the model coefficients. Though a quadratic model does not have a linear shape when plotted, for example, it is classified as a linear model in regression analysis since it is linear with respect to the model coefficients.) 5.2 This practice does not limit the use of a linear regression model with more than one predictor variable or other statistical models if justified as more appropriate for the â versus a data. 5.3 This practice is not appropriate for data resulting from a POD examination on nondestructive evaluation systems that generate an initial response that is binary in nature (for example, hit/miss). Practice E2862 is appropriate for systems that generate a hit/miss-type response (for example, fluorescent penetrant). 5.4 Prior to performing the analysis, it is assumed that the discontinuity of interest is clearly defined; the number and distribution of induced discontinuity sizes in the POD specimen set is known and well documented; the POD examination administration procedure (including data collection method) is well designed, well defined, under control, and unbiased (see X1.2.2 for more detail); the initial inspection system response is measurable and continuous in nature; the inspection system is calibrated; and the measurement error has been evaluated and deemed acceptable. The analysis results are only valid if the â versus a data are accurate and precise and the linear model adequately represents the â versus a data. 5.5 The POD analysis method described herein is consistent with the analysis method for â versus a data described in MIL-HDBK-1823A and is included in several widely utilized POD software packages to perform a POD analysis on â versus a data. It is also found in statistical software packages that have linear regression analysis capability. This practice requires that the analyst has access to either POD software or other software with linear regression analysis capability.