D'Alonzo Karen T
College of Nursing, Rutgers, The State University of New Jersey, Newark 07102, USA.
West J Nurs Res. 2004 Nov;26(7):804-12. doi: 10.1177/0193945904266733.
ANCOVA is a widely used statistical procedure that is particularly useful in analyzing data from experimental designs. There are, however, a number of assumptions that must be tested before proceeding with the ANCOVA. Of particular concern is the assumption of homogeneity of regression slopes (HOS). When the HOS assumption has been violated, the researcher needs to look for an alternative approach to the ANCOVA. The Johnson-Neyman procedure (J-N) is presented as such an alternative. Although the calculations for the procedure are somewhat tedious and are not currently a standard feature of statistical software packages, an alternative approach using SAS syntax codes is presented.
协方差分析（ANCOVA）是一种广泛使用的统计方法，在分析实验设计的数据时特别有用。然而，在进行协方差分析之前，有许多假设必须进行检验。特别值得关注的是回归斜率同质性（HOS）假设。当违反HOS假设时，研究人员需要寻找协方差分析的替代方法。本文介绍了约翰逊 - 奈曼法（J - N）作为这样一种替代方法。尽管该方法的计算有些繁琐，且目前不是统计软件包的标准功能，但本文介绍了一种使用SAS语法代码的替代方法。
