Statistical models that involve a two-part mixture distribution are applicable in a variety of situations. Frequently, the two parts are a model for the binary response variable and a model for the outcome variable that is conditioned on the binary response. Two common examples are zero-inflated or hurdle models for count data and two-part models for semicontinuous data. Recently, there has been particular interest in the use of these models for the analysis of repeated measures of an outcome variable over time. The aim of this review is to consider motivations for the use of such models in this context and to highlight the central issues that arise with their use. We examine two-part models for semicontinuous and zero-heavy count data, and we also consider models for count data with a two-part random effects distribution.

中文翻译：

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纵向数据的两部分和相关回归模型。

涉及两部分混合分布的统计模型适用于各种情况。通常，这两个部分是二元响应变量的模型和以二元响应为条件的结果变量的模型。两个常见的示例是计数数据的零膨胀或障碍模型以及半连续数据的两部分模型。最近，人们对使用这些模型来分析结果变量随时间的重复测量产生了特别的兴趣。本次审查的目的是考虑在这种情况下使用此类模型的动机，并强调使用它们时出现的核心问题。我们检查半连续和零重计数数据的两部分模型，并且我们还考虑具有两部分随机效应分布的计数数据模型。