This article provides a brief overview of confirmatory tetrad analysis (CTA) and presents a new set of Stata commands for conducting CTA. The tetrad command allows researchers to use model-implied vanishing tetrads to test the overall fit of structural equation models (SEMs) and the relative fit of two SEMs that are tetrad-nested. An extension of the command, tetrad_matrix, allows researchers to conduct CTA using a sample covariance matrix as input rather than relying on raw data. Researchers can also use the tetrad_matrix command to input a polychoric correlation matrix and conduct CTA for SEMs involving dichotomous, ordinal, or censored outcomes. Another extension of the command, tetrad_bootstrap, provides a bootstrapped p value for the chi-square test statistic. With Stata’s recently developed commands for structural equation modeling, researchers can integrate CTA with data preparation, likelihood ratio tests for model fit, and the estimation of model parameters in a single statistical software package.

中文翻译：

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四元组：一组用于确认四元组分析的 Stata 命令

本文简要概述了验证性四元分析 (CTA)，并提供了一组用于执行 CTA 的新 Stata 命令。四分体命令允许研究人员使用模型隐含的消失四分体来测试结构方程模型 (SEM) 的整体拟合以及四分体嵌套的两个 SEM 的相对拟合。命令的扩展 tetrad_matrix 允许研究人员使用样本协方差矩阵作为输入进行 CTA，而不是依赖原始数据。研究人员还可以使用 tetrad_matrix 命令输入多色相关矩阵，并对涉及二分、有序或删失结果的 SEM 进行 CTA。命令的另一个扩展 tetrad_bootstrap 为卡方检验统计量提供自举 p 值。借助 Stata 最近开发的用于结构方程建模的命令，