54 research outputs found
A new method for the estimation of variance matrix with prescribed zeros in nonlinear mixed effects models
We propose a new method for the Maximum Likelihood Estimator (MLE) of
nonlinear mixed effects models when the variance matrix of Gaussian random
effects has a prescribed pattern of zeros (PPZ). The method consists in
coupling the recently developed Iterative Conditional Fitting (ICF) algorithm
with the Expectation Maximization (EM) algorithm. It provides positive definite
estimates for any sample size, and does not rely on any structural assumption
on the PPZ. It can be easily adapted to many versions of EM.Comment: Accepted for publication in Statistics and Computin
Benthic-pelagic coupling in the population dynamics of the harmful cyanobacterium Microcystis
Random effects diagonal metric multidimensional scaling models
By assuming a distribution for the subject weights in a diagonal metric (INDSCAL) multidimensional scaling model, the subject weights become random effects. Including random effects in multidimensional scaling models offers several advantages over traditional diagonal metric models such as those fitted by the INDSCAL, ALSCAL, and other multidimensional scaling programs. Unlike traditional models, the number of parameters does not increase with the number of subjects, and, because the distribution of the subject weights is modeled, the construction of linear models of the subject weights and the testing of those models is immediate. Here we define a random effects diagonal metric multidimensional scaling model, give computational algorithms, describe our experiences with these algorithms, and provide an example illustrating the use of the model and algorithms.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45758/1/11336_2005_Article_BF02295730.pd
Reducing Peritonitis Rates in a Peritoneal Dialysis Program of Indigent Ethnic Minorities
How Accurate is the Description of Transport Kinetics in Peritoneal Dialysis According to Different Versions of the Three-Pore Model?
The Success Story of Peritoneal Dialysis in Romania: Analysis of Differences in Mortality by Dialysis Modality and Influence of Risk Factors in a National Cohort
The Effect of a Tai Chi Exercise Program on Quality of Life in Patients on Peritoneal Dialysis: A Pilot Study
A Multicenter, Selection-Adjusted Comparison of Patient and Technique Survivals on CAPD and Hemodialysis
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