With the fast evolution of high-throughput technology, longitudinal gene expression experiments have become affordable and increasingly common in biomedical fields. Generalized estimating equation (GEE) approach is a widely used statistical method for analysis data. Feature selection imperative omics data analysis. Among variety existing feature methods, an embedded method—threshold gradient de...

We consider the problem of calculating power and sample size for tests based on generalized estimating equations (GEE), that arise in studies involving clustered or correlated data (e.g., longitudinal studies and sibling studies). Previous approaches approximate the power of such tests using the asymptotic behavior of the test statistics under fixed alternatives. We develop a more accurate appr...

Generalized linear models (GLMs) are increasingly being used in daily data analysis. However, model checking for GLMs with correlated discrete response data remains difficult. In this paper, through a case study on marginal logistic regression using a real data set, we illustrate the flexibility and effectiveness of using conditional moment tests (CMTs), along with other graphical methods, to d...

A SAS/IML software program is described that computes regression diagnostics for generalized estimating equations. These diagnostics are computationally efficient and accurate approximations for the effect of deleting one observation or one cluster on individual regression coefficients (DFBETA) or on the overall fit of the model (Cook’s Distance). New formulae for the diagnostics are presented ...

HIV (Human Immunodeficiency Virus) researchers are often concerned with the correlation between HIV viral load measurements and CD4+ lymphocyte counts. Due to the lower limits of detection (LOD) of the available assays, HIV viral load measurements are subject to left-censoring. Motivated by these considerations, the maximum likelihood (ML) method under normality assumptions was recently propose...

In Augustus 1966 het mnr en mev D ’Oliveira medestigters geword van Operation Upgrade o f Southern Africa. Vandag is die organisasie wat vier opleidingsentra oor die hele Suid-Afrika het, besig met ’n veldtog om ongeletterdheid oor die hele Republiek uit te wis — ’n veldtog wat die stigters oor die hele vasteland van Afrika wil voer om brúe van begrip en goedgesindheid tussen die Noorde en Suid...