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...e, the glmmPQL converges only and give good results when k is less than 3 (i.e. for a small number of random effects). I also used the gee (generalized estimating equations) to estimate the fixed effects and the same probleme ariseed with k. Is there any help? Thank you in advance, Abderrahim Oulhaj [[alternative HTML version deleted]]

Hi, I am looking for any procedure in R to fit "Latent variables models" in particular "Latent trait models (i.e. for binary data)". could anyone help me? Many thanks , Dr Abderrahim Oulhaj Oxford University Department of Pharmacology Mansfield Road Oxford OX1 3QT Tel: +44 1865 224098 Fax: +44 1865 224099 Email: abderrahim.oulhaj@pharmacology.oxford.ac.uk [[alternative HTML version deleted]]

...Group Residuals: Min Q1 Med Q3 Max -3.122723638 -0.451811989 0.001009602 0.540504726 2.398619776 Number of Observations: 495 Number of Groups: 211 I think its a problem of local optimum...... Help!!!! Many thanks, Abderrahim Dr Abderrahim Oulhaj Oxford University Department of Pharmacology Mansfield Road Oxford OX1 3QT Tel: +44 1865 224098 Fax: +44 1865 224099 Email: abderrahim.oulhaj@pharmacology.oxford.ac.uk [[alternative HTML version deleted]]

...ot;nlme" library allows the introduction of time varying covariates ? For example how can I interpret the xmid parameter (reperesenting the age at which we reach the half of the asymptote) if I want to explain it by a some time varying covariate? Thanks in adavance, Abderrahim Abderrahim Oulhaj, Phd in Statistics Oxford University Department of Pharmacology Mansfield Road Oxford OX1 3QT Tel: +44 1865 224098 Fax: +44 1865 224099 Email: abderrahim.oulhaj@pharmacology.oxford.ac.uk [[alternative HTML version deleted]]

Dear All, I wonder if there is a way to fit a generalized linear mixed models (for repeated binomial data) via a direct Maximum Likelihood Approach. The "glmm" in the "repeated" package (Lindsey), the "glmmPQL" in the "MASS" package (Ripley) and "glmmGIBBS" (Myle and Calyton) are not using the full maximum likelihood as I understand. The

Dear All, I have the following error message when I fitted lmer to a binary data with the "AGQ" option: Error in family$mu.eta(eta) : NAs are not allowed in subscripted assignments In addition: Warning message: IRLS iterations for PQL did not converge Any help? Thanks in advance, Abderrahim [[alternative HTML version deleted]]

Dear R users, I have a question concerning the nltm package. Before posting to the R list I first contacted the author of the package twice but no succes. May be I've got the wrong email! My question is about the object "surv" given in the package "nltm". As explained, the object "surv" represents the MLE estimates of the baseline survival function evaluated at

Dear all, I didn't get any suggestion for my querry concerning the NLTM package so I am re-posting it hoping that someone can give me any clue. I apologize for doing so. Please find attached a copy of my previous email: Dear R users, I have a question concerning the nltm package. Before posting to the R list I first contacted the author of the package twice but no succes. May be I've

Dear All, I wonder if there is an R package to estimate the generalized linear mixed models but with a random effects having a mixture of normals as a prior distributinon .. Thank you, Abderrahim [[alternative HTML version deleted]]