Displaying 20 results from an estimated 7000 matches similar to: "Advice on analyzing a mixed effects survival model?"
2002 Sep 17
2
Feature request: Sync Mac OS resource forks and metadata on Mac OS X
I have a feature request for rsync. I tried posting it to the
FAQ-o-matic, but that system didn't seem to be accepting new
questions. I hope this is an okay list for the request--apologies if
it's misdirected.
Mac OS X provides support for the Mac file system resource forks and
mac specific metadata (e.g., creator and file type). Most Unix
applications ignore this information, but it
2005 Apr 30
0
lmer for mixed effects modeling of a loglinear model
I have a dataset with 25 subjects and 25 items. For each subject-item
combination, there's a 0/1 score for two parts, A and B. I'm thinking
of this as a set of 2 x 2 tables, 25 x 25 of them. I'd like to fit a
log-linear model to this data to test the independence of the A and B
scores.
If I ignore the subject and item parts, the following works just fine:
glm(count ~ A * B,
2002 Jan 22
1
lme and mixed effects
Dear r-help,
With lme, is there a way to specify multiple fixed factors under one level of grouping?
For example, for a single fixed factor, I use the following:
fm1.lme <- lme(fixed=resp ~ fact1, random=~1|subj/fact1, data=mydata)
I would like to have multiple factors under subj, like the following
for a two-way design, but I get an error:
fm2.lme <- lme(fixed=resp ~ fact1*fact2,
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
2009 Oct 01
0
General mixed effects Cox models
After an extremely long gestation, a new version of the coxme package is
now available on CRAN. This function fits very general mixed-effects
Cox models using an lmer-like syntax. For instance here is a model that
fits a random treatment effect, using data from a multi-study
collaboration.
fit <- coxme(Surv(pg.time, pg.stat) ~ stage + trt + (trt|site) +
stata(site), data=
2009 Oct 01
0
General mixed effects Cox models
After an extremely long gestation, a new version of the coxme package is
now available on CRAN. This function fits very general mixed-effects
Cox models using an lmer-like syntax. For instance here is a model that
fits a random treatment effect, using data from a multi-study
collaboration.
fit <- coxme(Surv(pg.time, pg.stat) ~ stage + trt + (trt|site) +
stata(site), data=
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
2010 Mar 11
1
mixed-effects survival
Hi,
What R libraries should I use to implement mixed effects models with continuous time and discrete-time survival data? What if I have two crossed random effects? I'd appreciate any help.
Regards,
Hakan Demirtas
[[alternative HTML version deleted]]
2007 Apr 20
1
Hiding "Warning messages" in coxme output
Dear list,
I have been trying to use coxme in R 2.3.1.
When I use coxme in the following data sim.fr1, i get
"Warning messages: using 'as.environment(NULL)' is
deprecated"
Why does it occur?
How can I hide such warning message,
especially when coxme is under a loop?
Mohammad Ehsanul Karim (Institute of Statistical
Research and Training, University of Dhaka)
>
2004 Aug 11
1
Fwd: Enduring LME confusion… or Psychologists and Mixed-Effects
In my undertstanding of the problem, the model
lme1 <- lme(resp~fact1*fact2, random=~1|subj)
should be ok, providing that variances are homogenous both between &
within subjects. The function will sort out which factors &
interactions are to be compared within subjects, & which between
subjects. The problem with df's arises (for lme() in nlme, but not in
lme4), when
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)
2011 Dec 30
2
Joint modelling of survival data
Assume that we collect below data : -
subjects = 20 males + 20 females, every single individual is independence,
and difference
events = 1, 2, 3... n
covariates = 4 blood types A, B, AB, O
http://r.789695.n4.nabble.com/file/n4245397/CodeCogsEqn.jpeg
?m = hazards rates for male
?n = hazards rates for female
Wm = Wn x ?, frailty for males, where ? is the edge ratio of male compare to
female
Wn =
2010 Aug 04
5
Question regarding significance of a covariate in a coxme survival model
Hi,
I am running a Cox Mixed Effects Hazard model using the library coxme. I
am trying to model time to onset (age_sym1) of thought problems (e.g.
hearing voices) (sym1). As I have siblings in my dataset, I have
decided to account for this by including a random effect for family
(famid). My covariate of interest is Mother's diagnosis where a 0 is
bipolar, 1 is control, and 2 is major
2006 Feb 17
1
A unique 'click to call' project - Could use some advice <--one thing I forgot
In the example I posted previous, there is an obvious gaping security hole,
it would be trivial for someone to read the querystring and exploit it to
make free phone calls, spoof caller ID (if you allow the CallerID to be set
with a QueryString value), etc. You want to make damn sure that the URL is
not publicly accessible or somehow obsfucate the querystring, or use POST.
In my case, I
2006 Jul 20
2
(robust) mixed-effects model with covariate
Dear all,
I am unsure about how to specify a model in R and I thought of asking
some advice to the list. I have two groups ("Group"= A, B) of
subjects, with each subject undertaking a test before and after a
certain treatment ("Time"= pre, post). Additionally, I want to enter
the age of the subject as a covariate (the performance on the test is
affected by age),
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
2012 Sep 06
1
How to extract p value from the lmekin object obtained by fitting mixed model with function lmekin() in package coxme?
Hi, R experts
I am currently using lmekin() function in coxme package to fit a
mixed effect model for family based genetic data. How can I extract the p
value from a lmekin object? When I print the object in R console, I can
see the p value and Z value are just over there. But I can not extract them
by the coef() function. kinfit$coefficient$fixed (kinfit is the name of the
lmekin object)
2004 Aug 10
4
Enduring LME confusion… or Psychologists and Mixed-Effects
Dear ExpeRts,
Suppose I have a typical psychological experiment that is a
within-subjects design with multiple crossed variables and a continuous
response variable. Subjects are considered a random effect. So I could model
> aov1 <- aov(resp~fact1*fact2+Error(subj/(fact1*fact2))
However, this only holds for orthogonal designs with equal numbers of
observation and no missing values.
2009 Aug 13
0
Need Advice: Considering Converting a Package from S3 to S4 -- reprise
I read the list in digest form which sometimes makes me late to respond.
Peter Dalgaard wrote:
In all fairness, it should probably be noted that quite a few people
swear BY S4 in addition to those who swear AT it.
Lest I give the impression of only dislike -- the coxme package (major
rewrite nearly done, I'm now testing) depends heavily on the bdsmatrix
package which implements a very
2003 Oct 04
2
mixed effects with nlme
Dear R users:
I have some difficulties analizing data with mixed effects NLME and the
last version of R. More concretely, I have a repeated measures design with
a single group and 2 experimental factors (say A and B) and my interest is
to compare additive and nonadditive models.
suj rv A B
1 s1 4 a1 b1
2 s1 5 a1 b2
3 s1 7 a1 b3
4 s1 1 a2