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标志物与潜在健康状态的联合模型AI 解读

Summary We extend the bivariate Wiener process considered by Whitmore and co-workers and model the joint process of a marker and health status. The health status process is assumed to be latent or unobservable. The time to reach the primary end point or failure (death, onset of disease, etc.) is the time when the latent health status process first crosses a failure threshold level. Inferences for the model are based on two kinds of data: censored survival data and marker…

允许数据缺失的多特征随机效应模型AI 解读

The use of random-effects models for the analysis of longitudinal data with missing responses has been discussed by several authors. This article extends the random-effects model for a single characteristic to the case of multiple characteristics, allowing for arbitrary patterns of observed data. Two different structures for the covariance matrix of measurement error are considered: uncorrelated error between responses and correlation of error terms at the same measurement…

比例风险回归模型的偏残差AI 解读

Residuals are defined for the proportional hazards regression model introduced by Cox (1972). These residuals can be plotted against time to test the proportional hazards assumption. Histograms of these residuals can be used to examine fit and detect outlying covariate values.

比较生存分布的非参数检验的渐近性质AI 解读

The asymptotic distribution under alternative hypotheses is derived for a class of statistics used to test the equality of two survival distributions in the presence of arbitrary, and possibly unequal, right censoring. The test statistics include equivalents to the log rank statistic, the modified Wilcoxon statistic and the class of rank invariant test procedures introduced by Peto & Peto. When there are equal censoring distributions and the hazard functions are proportional…

参数估计下基于克拉美–冯·米塞斯统计量正交分量线性组合的检验AI 解读

In a previous work, the author showed how linear combinations of the orthogonal components of the Cramer-von Mises statistic could be used to test fit to a fully specified distribution function. In this paper, the results are extended to the case where $r$ parameters are estimated from the data. It is shown that if the coefficient vector of the linear combination is orthogonal to a specified $r$ dimensional subspace, then the asymptotic distribution of that combination is…

A class of omnibus chi-squared goodness-of-fit tests is presented for the model, relating failure time to covariate values, proposed by Cox (1972). These tests are based on the expected and observed frequency that a data point, representing a failure with associated covariates, falls into one of L mutually exclusive categories. Different partitions of the space of covariate values and failure time will yield different tests. Certain partitions are suggested for the…

比例风险回归模型的卡方拟合优度检验AI 解读

A class of omnibus chi-squared goodness-of-fit tests is presented for the model, relating failure time to covariate values, proposed by Cox (1972). These tests are based on the expected and observed frequency that a data point, representing a failure with associated covariates, falls into one of L mutually exclusive categories. Different partitions of the space of covariate values and failure time will yield different tests. Certain partitions are suggested for the…