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arXiv 2104.06872stat.ME
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基于Copula函数的相依删失

Dependent censoring based on copulas

Claudia Czado, Ingrid Van Keilegom

摘要:

考虑生存时间T服从随机右删失,并假设T随机依赖于删失时间C。我们感兴趣的是T的边缘分布。这种情况在实践中经常遇到。例如,考虑T是患有某种疾病的患者的死亡时间的情况。然后,删失时间C例如是直到该人离开研究的时间或直到他/她死于另一种疾病的时间。如果退出研究的原因与患者的健康状况有关,或者如果他/她死于与关注疾病具有相似风险因素的疾病,则T和C可能具有依赖性。在本文中,我们提出了一个新的模型,考虑到这种依赖。该模型基于T和C之间关系的参数copula,以及T和C的参数边缘分布。与文献中的大多数其他论文不同,我们不假设定义Copula函数的参数是已知的。我们给出了关于这些参数Copula和边缘的充分条件,在此条件下,(T;C)的二元分布被确定。这些充分条件,然后检查范围广泛的共同copula和边缘分布。我们还研究了模型的估计,并进行了广泛的模拟和胰腺癌的数据分析,以说明所提出的模型和估计程序。

英文摘要:

Consider a survival time T that is subject to random right censoring, and suppose that T is stochastically dependent on the censoring time C. We are interested in the marginal distribution of T. This situation is often encountered in practice. Consider for instance the case where T is the time to death of a patient suffering from a certain disease. Then, the censoring time C is for instance the time until the person leaves the study or the time until he/she dies from another disease. If the reason for leaving the study is related to the health condition of the patient or if he/she dies from a disease that has similar risk factors as the disease of interest, then T and C are likely dependent. In this paper we propose a new model that takes this dependence into account. The model is based on a parametric copula for the relationship between T and C, and on parametric marginal distributions for T and C. Unlike most other papers in the literature, we do not assume that the parameter defining the copula function is known. We give sufficient conditions on these parametric copula and marginals under which the bivariate distribution of (T;C) is identifed. These sufficient conditions are then checked for a wide range of common copulas and marginal distributions. We also study the estimation of the model, and carry out extensive simulations and the analysis of data on pancreas cancer to illustrate the proposed model and estimation procedure.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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