Displaying 20 results from an estimated 500 matches similar to: "Generation from COX PH with gamma frailty"
2009 Jun 05
2
p-values from VGAM function vglm
Anyone know how to get p-values for the t-values from the coefficients
produced in vglm?
Attached is the code and output ? see comment added to output to show
where I need p-values
+ print(paste("********** Using VGAM function gamma2 **********"))
+ modl2<-
vglm(MidPoint~Count,gamma2,data=modl.subset,trace=TRUE,crit="c")
+ print(coef(modl2,matrix=TRUE))
2009 Jun 26
1
predicted values after fitting gamma2 function
Question: after fitting a gamma function to some data, how do I get
predicted values? I'm a SAS programmer, I new R, and am having
problems getting my brain to function with the concept of "object as
class ...". The following is specifics of what I am doing:
I'm trying to determine the pdf from data I have created in a
simulation.
I have generated frequency counts
2006 Oct 27
0
VGAM package released on CRAN
Dear useRs,
upon request, the VGAM package (currently version 0.7-1) has been
officially released on CRAN (the package has been at my website
http://www.stat.auckland.ac.nz/~yee/VGAM for a number of years now).
VGAM implements a general framework for several classes of
regression models using iteratively reweighted least squares
(IRLS). The key ideas are Fisher scoring, generalized linear
and
2016 Apr 18
0
R [coding : do not run for every row ]
You can make this much more readable with apply functions.
result <- apply(
all_combine1,
1,
function(x){
p.value <- sapply(
seq_len(nSims),
function(sim){
gamma1 <- rgamma(x["m"], x["sp(skewness1.5)"], x["scp1"])
gamma2 <- rgamma(x["n"], x["scp1"], 1)
gamma1 <- gamma1 -
2016 Apr 18
0
R [coding : do not run for every row ]
Always keep the mailing list in cc.
The code runs for each row in the data. However I get the feeling that
there is a mismatch between what you think that is in the data and the
actual data.
ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature
and Forest
team Biometrie & Kwaliteitszorg / team Biometrics & Quality Assurance
Kliniekstraat 25
1070
2016 Apr 19
0
problem on simulation code (the loop unable to function effectively)
Hi Jeem,
First, please send questions like this to the help list, not me.
I assume that you are in a similar position to sjtan who has been
sending almost exactly the same questions.
The problem is not in the loops (which look rather familiar to me) but
in your initial assignments at the top. For instance:
scale parameter=(1,1.5,2,2.5,3)
produces an error which has nothing to do with the
2016 Apr 19
0
problem on simulation code (the loop unable to function effectively)
Hi Si Jie,
Again, please send questions to the list, not me.
Okay, I may have worked out what you are doing. The program runs and
produces what I would expect in the rightmost columns of the result
"g".
You are storing the number of each test for which the p value is less
than 0.05. It looks to me as though the objects storing the results
should be vectors as you are only storing 100 p
2016 Apr 18
3
R [coding : do not run for every row ]
Hi, i am sorry, the output should be values between 0 and 0.1 and not supposed to be 1.00, it is because they are type 1 error rate. And now i get output 1.00 for several samples,rhis is no correct. The loop do not run for every row. i do not know where is my mistake. As i use the same concept on normal distribution setup, i get the result.
Sent from my phone
On Thierry Onkelinx
2013 Apr 17
1
Bug in VGAM z value and coefficient ?
Dear,
When i multiply the y of a regression by 10, I would expect that the
coefficient would be multiply by 10 and the z value to stay constant. Here
some reproducible code to support the case.
*Ex 1*
library(mvtnorm)
library(VGAM)
set.seed(1)
x=rmvnorm(1000,sigma=matrix(c(1,0.75,0.75,1),2,2))
2007 Apr 08
0
Simulation of the Frailty of the Cox PH model
Dear R-list users,
I am trying to do simulation of survival data to
enable it to run under frailty option. Below is the
function a that I am using. My questions are:
1. How do I modify it to get bigger (hopefully
significant) value of Variance of random effect?
2. What changes do I have to make in the function to
run it under correlated frailty model? (may be in
kinship package)
3. Is there
2016 Apr 17
2
R [coding : do not run for every row ]
i have combined all the variables in a matrix, and i wish to conduct a simulation row by row.
But i found out the code only works for the every first row after a cycle of nine samples.
But after check out the code, i don know where is my mistake...
can anyone pls help ....
#For gamma disribution with equal skewness 1.5
#to evaluate the same R function on many different sets of data
2007 Oct 29
1
VGAM and vglm
Hi Folks,
I wonderif someone who is familiar with the details
of vglm in the VGAM package can assist me. I'm new
to using it, and there doesn;t seem much in the
documentation that's relevant to the question below.
Say I have a vector x of 0/1 responses and another
vector y of 0/1 responses, these in fact being a
bivariate set of 0/1 responses equivalent to
cbind(x,y).
E.g.
2016 Apr 18
0
R [coding : do not run for every row ]
Dear anonymous,
The big mistake in the output might be obvious to you but not to
others. Please make clear what the correct output should be or at
least what is wrong with the current output.
And please DO read the posting guide which asks you not to post in HTML.
ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature
and Forest
team Biometrie &
2008 Jan 07
0
R vglm new family writing: mix Poisson/multinomial
Hi dear R users,
1)
I would like to know if there is a simple way to define a vglm family which
would be a mix of poisson variables and bernoulli variables (0/1 response)
for idea this would be invoked like this:
vglm(...,family=mixpoissonmultinom(npoisson,n01response))
where the n's give the number of each type of response.
2)
and a simpler question : How to use constraints in rrvglm?
2009 Nov 04
1
vglm(), t values and p values
Hi All,
I'm fitting an proportional odds model using vglm() from VGAM.
My response variable is the severity of diseases, going from 0 to 5 (the
severity is actually an ordered factor).
The independent variables are: 1 genetic marker, time of medical observation,
age, sex. What I *need* is a p-value for the genetic marker. Because I have ~1.5
million markers I'd rather not faffing
2007 Jan 06
2
Using VGAM's vglm function for ordinal logistic regression
R-Experts:
I am using the vglm function of the VGAM library to perform proportional
odds ordinal logistic regression. The issue that I would like help with
concerns the format in which the response variable must be provided for
this function to work correctly. Consider the following example:
------
library(VGAM)
library(MASS)
attach(pneumo)
pneumo # Inspect the format of the original dataset
2012 Apr 04
0
multivariate ordered probit regression---use standard bivariate normal distribution?
Hello.
I have yet to receive a response to my previous post, so I may have
done a poor job asking the question. So, here is the general question:
how can I run a run a multivariate (more than one non-independent,
response variables) ordered probit regression model? I've had success
doing this in the univariate case using the vglm() function in the
VGAM package. For example:
2011 Jun 07
0
WinBUGS on survival, simple but confusing question
Hi All,
I'm using WinBUGS on a very simple survival model (log-normal with one
covariate "Treat"), but I cannot understand the way it handles censored
data. I'm posting the R file which generates the data from pre-specified
parameters, as well as the .bug file.
The question is, if I use NA to denote the censored data (as suggested by
the example Mice in WinBUGS Example Vol.I),
2012 Jan 10
1
S4 summary method not being called (VGAM)
The symptom triggering this email is that an S4 summary method sometimes refuses to be invoked, even when a package is explicitly loaded, if the first load of the package is implicit. It may or may not be specific to 'summary' methods and/or the 'VGAM' package. I've sent to R-devel because (i) it looks like some kind of bug to me, but I'm not sure; (ii) it's not
2011 Aug 23
1
P values for vglm(zibinomial) function in VGAM
Hi ,
I know this question has been asked twice in the past but to my knowldege,
it still hasn't been solved.
I am doing a zero inflated binomial model using the VGAM package, I need to
obtain p values for my Tvalues in the vglm output. code is as follows
> mod2=vglm(dmat~Season+Diel+Tidal.phase+Tidal.cycle,zibinomial, data=mp1)
> summary(mod2)
Call:
vglm(formula = dmat ~ Season +