Modelling the random effects covariance matrix in longitudinal data
نویسندگان
چکیده
منابع مشابه
Estimation of the Covariance Matrix of Random Effects in Longitudinal Studies
Longitudinal studies are often conducted to explore the cohort and age effects in many scientific areas. The within cluster correlation structure plays a very important role in longitudinal data analysis. This is because not only can an estimator be improved by incorporating the within cluster correlation structure into the estimation procedure, but also the within cluster correlation structure...
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ژورنال
عنوان ژورنال: Statistics in Medicine
سال: 2003
ISSN: 0277-6715,1097-0258
DOI: 10.1002/sim.1470