search for: heagerty

Hi, I'm reading van Belle et al "Biostatistics" and trying to run a cox test using a dataset from: http://faculty.washington.edu/~heagerty/Books/Biostatistics/chapter16.html (Primary Biliary Cirrhosis data link at top of the page), I'm using the following code: --------------- start of code library(survival) liver <- scan("liver2.txt",list(age=0,albumin=0,alkphos=0,ascites=0,bili=0, cholest=0,edema=0,edmadj...

...dom-Intercept Models of Correlated Binary Outcomes. International Statistical Review, 82 (2), 275-295 1-22. <DOI: 10.1111/insr.12035> Griswold, M.E., Swihart, B.J., Caffo, B.S and Zeger, S.L. (2013). Practical marginalized multilevel models. Stat, 2(1), 129-142. <DOI: 10.1002/sta4.22> Heagerty, P.J. (1999). Marginally specified logistic-normal models for longitudinal binary data. Biometrics, 55(3), 688-698. <DOI: 10.1111/j.0006-341X.1999.00688.x> Heagerty, P.J. and Zeger, S.L. (2000). Marginalized multilevel models and likelihood inference (with comments and a rejoinder by the aut...

Hey all, In order to test if a marker is a risk factor, I built two models (using cox proportional hazard model). One model included this marker, and the other is not. Then, I use R package risksetROC to test how much predictive value did the marker add to this model. I get two C statistics by analyzing the linear predictors of the two models into this package. The qustion is How to test if two

Hi, I'm trying to figure out if there are any packages allowing one to fit mixed models (or non-linear mixed models) to data that includes censoring. I've done some searching already on CRAN and through the mailing list archives, but haven't discovered anything. Since I may well have done a poor job searching I thought I'd ask here prior to giving up. I understand that

...timators in a rather flexible way, allowing for user-defined weights or weight functions. It builds on some of the functionality which was before available in Thomas Lumley's weave package (not on CRAN). In particular it makes available the class of WEAVE estimators introduced by Lumley & Heagerty (1999) in the function weave() which is a convenience interface to vcovHAC(). Furthermore, it implements the class of kernel HAC estimators with automatic bandwidth-selection of Andrews (1991) in the function kernHAC(), which is again a convenience interface to vcovHAC(). Best wishes, Z ---------...

...timators in a rather flexible way, allowing for user-defined weights or weight functions. It builds on some of the functionality which was before available in Thomas Lumley's weave package (not on CRAN). In particular it makes available the class of WEAVE estimators introduced by Lumley & Heagerty (1999) in the function weave() which is a convenience interface to vcovHAC(). Furthermore, it implements the class of kernel HAC estimators with automatic bandwidth-selection of Andrews (1991) in the function kernHAC(), which is again a convenience interface to vcovHAC(). Best wishes, Z ---------...

I want to run a GEE for a time series of counts. The data are daily respiratory mortality counts and so there aren't any 'clusters' in the longitudinal sense. Neither the gee or geese packages work. The gee one wont run at all and the geese one produces NaNs or just runs indefinitely depending on how long the time series is. Any ideas how to make these work of any other packages that

...long time. Although they are most often used for continuous response variables they work perfectly well for counts. Stata 7.0 does the Newey-West estimator for generalised linear models, which may be what you had heard about. These and related sandwich-type estimators are reviewed by Lumley & Heagerty (JRSSB 1999,pp459-477). I have R code, but again only for generalised linear models, not for zero-inflation models." Thomas added: - The Poisson-Normal model leads to a loglinear marginal model that can be fitted by glm(), and I would expect something similar to be true of the zero-inflatio...

hi all- I am doing some research, have never used R before until today and need to understand the following program for a project. if some one could PLEASE help me understand this program ASAP i would GREATLY appreciate it (any syntax/ statistic comments would be great) PLEASE PLEASE HELP!! THANKYOU!!! -on a side note, it seems to me that R doesnt include the pv, and it was calculated

Dear all, I am interested to evaluate reclassification using net reclassification improvement and Integrated Discrimination Index IDI after survival analysis (Cox proportional hazards using stcox). I search a R package or a R code that specifically addresses the categorical NRI for time-to-event data in the presence of censored observation and, if possible, at different follow-up time points. I