similar to: General mixed effects Cox models

Displaying 20 results from an estimated 10000 matches similar to: "General mixed effects Cox models"

2013 Apr 30
0
Cox model: random effect on a variable with 3 levels
Question about package Coxme: I develop a cox model that includes a variable "treatment" with 3 levels (A, B, C): > model_alea_int <- coxme(Surv(delai, status) ~ (1|trt)+ strata(center) , data) I am surprised that the output given in R is 3 coefficients for random effects whereas only 2 dummy variables are created: > contrasts(data$trt) B C A 0 0 B 1 0 C
2006 Jul 05
0
Problem with coxme
------------- Begin Forwarded Message ------------- Date: Wed, 5 Jul 2006 09:09:14 -0500 (CDT) From: Terry Therneau <therneau at mayo.edu> Subject: RE: Problem with coxme To: jhz22 at medschl.cam.ac.uk Cc: R-help at stat.mat.ethz.ch, liulei at virginia.edu, spencer.graves at pdf.com Content-MD5: BXKVsHtW/1I9mIUqrXBU0g== The original question involved a strange error message from coxme
2010 Aug 22
2
coxme AIC score and p-value mismatch??
Hi, I am new to R and AIC scores but what I get from coxme seems wrong. The AIC score increases as p-values decrease. Since lower AIC scores mean better models and lower p-values mean stronger effects or differences then shouldn't they change in the same direction? I found this happens with the data set rats as well as my own data. Below is the output for two models constructed with the rats
2013 Jun 04
0
Mixed effects model with a phylogenetic tree/ distance, matrix as a random effect
Take a look at lmekin() in the coxme package. The motivating data set for my development of coxme was the Minnesota Family Breast Cancer project: 24050 subjects in 462 families. The random effect is an intercept per subject with sigma^2 K as its variance where K is the kinship matrix (1 for self-self, .5 for parent-child or sib-sib, .25 for uncle-neice, etc). lmekin is a linear models front
2006 Feb 03
0
Mixed-effects models / heterogenous covariances
> Message: 24 > Date: Tue, 31 Jan 2006 18:22:52 +0000 > From: "Lutz Ph. Breitling" <lutz.breitling at gmail.com> > Subject: [R] Mixed-effects models / heterogeneous covariances > To: r-help at stat.math.ethz.ch > Message-ID: > <2e38a1c80601311022i2e1be92doa60b80b50b69eb0c at mail.gmail.com> > Content-Type: text/plain; charset=ISO-8859-1 > > Dear
2006 Jan 18
2
Help with mixed effects models
Dear R-users I have problems using lme The model i want to fit can be viewed as a two-level bivariate model Two-level bivariate: bivariate (S coded as -1,T coded as 1) endpoint within trial OR It can equivalently be considered as a three-level model.Three-level: endpoint within patient, patient within trial. My code tries to model the levels through a RANDOM statement and a
2007 May 17
1
MICE for Cox model
R-helpers: I have a dataset that has 168 subjects and 12 variables. Some of the variables have missing data and I want to use the multiple imputation capabilities of the "mice" package to address the missing data. Given that mice only supports linear models and generalized linear models (via the lm.mids and glm.mids functions) and that I need to fit Cox models, I followed the previous
2007 Oct 22
2
Repeated Measures/Linear Mixed Effects function
I have three columns of data, Xc, Trt and fish. This was a repeated measures design with 6 measurements taken from each of 5 fish. Xc is the actual measurement, Trt is the treatment, and fish is the fish number. Data can be seen below (hopefully it is in the column format). I would like to look for differences between treatments in a repeated measures format. I used the following code
2012 Jul 18
0
Building a web risk calculator based on Cox, PH--definitive method for calculating probability?
Here is an example of how to do it. > library(survival) > vfit <- coxph(Surv(time, status) ~ celltype + trt, data=veteran) > userinput <- data.frame(celltype="smallcell", trt = 1) > usercurve <- survfit(vfit, newdata=userinput) #the entire predicted survival curve > user2 <- summary(usercurve, time= 2*365.25) # 2 year time point > user2$surv [1]
2015 Feb 16
0
Imports problem
>>>>> Therneau, Terry M , Ph D <therneau at mayo.edu> >>>>> on Sun, 15 Feb 2015 17:31:00 -0600 writes: > I'm testing out a new version of coxme and R CMD check fails with "could not find function > ranef" (or random.effects or fixef, or anything from nlme). The NAMESPACE file has the > line below >
2013 Feb 14
1
Nomogram after Cox Random Effect (frailty) model
Dear R-users, I am a novice R-user with some experience in using the RMS package for taking nomograms after various survival models. This time, I am trying to plot a nomogram after a Random Effects Cox, implemented by the "coxme" package. My questions are: 1. Is it possible to take a nomogram directly after the coxme survival function? 2. If not is there a way to take the linear
2009 Jan 12
1
help on nested mixed effects ANOVA
Hello, I am trying to run a mixed effects nested ANOVA but none of my codes are giving me any meaningful results and I am not sure what I am doing wrong. I am a new user on R and would appreciate some help. The experimental design is that I have some frogs that have been exposed to three acoustic Treatments and I am measuring neural activity (egr), in 12 brain regions. Some frogs also called
2008 Feb 14
1
Advice on analyzing a mixed effects survival model?
I have an experiment I'm trying to analyze that's turning out to be more complicated than I anticipated, so I was hoping for some suggestions about how to handle it. The lab experiment is a comparison between two search interfaces. After a little training, each subject performs 12 information search tasks, 6 with one interface and 6 with the other, and we measure time to
2002 Dec 15
2
Interpretation of hypothesis tests for mixed models
My question concerns the logic behind hypothesis tests for fixed-effect terms in models fitted with lme. Suppose the levels of Subj indicate a grouping structure (k subjects) and Trt is a two-level factor (two treatments) for which there are several (n) responses y from each treatment and subject combination. If one suspects a subject by treatment interaction, either of the following models seem
2011 Jul 08
1
coxme for random effects only model
Dear all, I have encountered the following problem where coxme seems to allow model with only random effect in R 2.11.1 but not in R 2.13.0. Following is the error message using rat example data. Any comment on this is appreciated. In R2.13 > library(coxme) > rat1 <- coxme(Surv(time, status) ~ rx + (1|litter), rats) > rat0 <- coxme(Surv(time, status) ~ (1|litter), rats)
2017 Dec 29
0
winbuilder warning message wrt function pointers
You can legally cast a function pointer to another function pointer, where the signatures differ. (It is not legal to cast between data and function pointers.) I would make typedefs for the various signatures, as the casting syntax is more readable then. Bill Dunlap TIBCO Software wdunlap tibco.com On Fri, Dec 29, 2017 at 10:13 AM, Therneau, Terry M., Ph.D. < therneau at mayo.edu> wrote:
2005 Oct 25
0
One more about Error in step() (or stepAIC) for Cox model
Thank you for Prof.Ripley's suggestion. I fixed the program by adding a lower scope, and the program ran, but I still got warning messages, and don't know what is going on, would this affect my results? ... Step: AIC= 12337.74 Surv(tlfup, cen) ~ MI[[j]]$trt + MI[[j]]$agem40 + MI[[j]]$agem40sq + mhtypeed1 + mhtypeed2 Df AIC <none> 12338 -
2005 Aug 18
1
R equivalent to `estimate' in SAS proc mixed
Example: I have the following model > model <- lmer(response ~ time * trt * bio + (time|id), data = dat) where time = time of observation trt = treatment group (0-no treatment / 1-treated) bio = biological factor (0-absent / 1-present) and I would like to obtain an estimate (with standard error) of the change in response over time for individuals in the
2010 Nov 02
2
multi-level cox ph with time-dependent covariates
Dear all, I would like to know if it is possible to fit in R a Cox ph model with time-dependent covariates and to account for hierarchical effects at the same time. Additionally, I'd like also to know if it would be possible to perform any feature selection on this model fit. I have a data set that is composed by multiple marker measurements (and hundreds of covariates) at different time
2009 Aug 13
2
CMD check error (bug?)
R version 2.9.0 running on Centos (Red Hat linux). I have a pair of packages coxme and bdsmatrix. The latter is installed in my local library (I don't have permission for global install at work.) That is, it is in the location pointed to in R_LIBS_USER. In R, the command library(bdsmatrix) works fine. Coxme depends on bdsmatrix, in fact uses some cross-calls to it's C routines, which