Displaying 20 results from an estimated 20000 matches similar to: "na.action in stats::factanal()"
2012 Feb 06
1
na.action in stats::factanal() must be using formula interface and dataframe input to specify na.action?
hi,
Does factanal() force the user to use the formula interface if they wish to specify an na.action?
v1 <- c(1,1,1,1,1,1,1,1,NA,1,3,3,3,3,3,4,5,6)
v2 <- c(1,2,1,1,1,1,2,1,2,1,3,NA,3,3,3,4,6,5)
v3 <- c(3,3,3,3,3,1,1,1,1,1,1,1,1,1,1,5,4,6)
v4 <- c(3,3,4,NA,3,1,1,2,1,1,1,1,2,NA,1,5,6,4)
v5 <- c(1,1,1,1,1,3,3,3,3,3,1,1,1,1,1,6,4,5)
v6 <- c(1,1,1,2,1,3,3,3,4,3,1,1,1,2,1,6,5,4)
m1
2013 Nov 14
1
issues with calling predict.coxph.penal (survival) inside a function
Thanks for the reproducable example. I can confirm that it fails on my machine using
survival 2-37.5, the next soon-to-be-released version,
The issue is with NextMethod, and my assumption that the called routine inherited
everything from the parent, including the environment chain. A simple test this AM showed
me that the assumption is false. It might have been true for Splus. Working this
2008 Jun 16
1
回复: cch() and coxph() for case-cohort
I tried to compare if cch() and coxph() can generate same result for
same case cohort data
Use the standard data in cch(): nwtco
Since in cch contains the cohort size=4028, while ccoh.data size =1154
after selection, but coxph does not contain info of cohort size=4028.
The rough estimate between coxph() and cch() is same, but the lower
and upper CI and P-value are a little different. Can we
2011 Mar 14
1
coxph and drop1
A recent question in r-help made me realize that I should add a drop1 method
for coxph and survreg. The default does not handle strata() or cluster()
properly.
However, for coxph the right options for the "test" argument would be
likelihood-ratio, score, and Wald; not chisq and F. All of them reference
a chi-square distribution. My thought is use these arguments, and add an
2018 Jan 18
1
Time-dependent coefficients in a Cox model with categorical variants
First, as others have said please obey the mailing list rules and turn of
First, as others have said please obey the mailing list rules and turn off html, not everyone uses an html email client.
Here is your code, formatted and with line numbers added. I also fixed one error: "y" should be "status".
1. fit0 <- coxph(Surv(futime, status) ~ x1 + x2 + x3, data = data0)
2. p
2008 Jun 12
1
cch function and time dependent covariates
----- begin included message
In case cohort study, we can fit proportional hazard regression model to
case-cohort data. In R, the function is cch() in Survival package
Now I am working on case cohort analysis with time dependent covariates
using cch() of "Survival" R package. I wonder if cch() provide this utility
or not?
The cch() manual does not say if time dependent covariate is
2011 Jan 07
2
survval analysis microarray expression data
For any given pre-specified gene or short list of genes, yes the Cox
model works fine. Two important caveats:
1. Remeber the rule of thumb for a Cox model of 20 events per variable
(not n=20). Many microarray studies will have very marginal sample
size.
2. If you are looking at many genes then a completely different strategy
is required. There is a large and growing literature; I like Newton
2012 Aug 09
1
basehaz() in package survival and warnings with coxph
I've never seen this, and have no idea how to reproduce it.
For resloution you are going to have to give me a working example of the
failure.
Also, per the posting guide, what is your sessionInfo()?
Terry Therneau
On 08/09/2012 04:11 AM, r-help-request at r-project.org wrote:
> I have a couple of questions with regards to fitting a coxph model to a data
> set in R:
>
> I have a
2007 May 07
1
Predicted Cox survival curves - factor coding problems..
The combination of survfit, coxph, and factors is getting confused. It is
not smart enough to match a new data frame that contains a numeric for sitenew
to a fit that contained that variable as a factor. (Perhaps it should be smart
enough to at least die gracefully -- but it's not).
The simple solution is to not use factors.
site1 <- 1*(coxsnps$sitenew==1)
site2 <-
2013 Oct 16
2
How to obtain restricted estimates from coxph()?
Hello,
I'm trying to use coxph() function to fit a very simple Cox proportional
hazards regression model (only one covariate) but the parameter space is
restricted to an open set (0, 1). Can I still obtain a valid estimate by
using coxph function in this scenario? If yes, how? Any suggestion would be
greatly appreciated. Thanks!!!
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2012 Nov 26
1
Plotting an adjusted survival curve
First a statistical issue: The survfit routine will produce predicted survival curves for
any requested combination of the covariates in the original model. This is not the same
thing as an "adjusted" survival curve. Confusion on this is prevalent, however. True
adjustment requires a population average over the confounding factors and is closely
related to the standardized
2013 Apr 24
2
Trouble Computing Type III SS in a Cox Regression
I should hope that there is trouble, since "type III" is an undefined concept for a Cox
model. Since SAS Inc fostered the cult of type III they have recently added it as an
option for phreg, but I am not able to find any hints in the phreg documentation of what
exactly they are doing when you invoke it. If you can unearth this information, then I
will be happy to tell you whether
2009 Jan 30
1
Factor Analysis-factanal function
Dear friends,
I'm using R to produce the following Factor Analysis:
> matriz.cor<-hetcor(matrix(as.factor(data), ncol=variables,
byrow=T))$correlations
> factanal(x=data, factors=2, covmat=matriz.cor, scores='regression')
Then the screen output shows the following message:
Error en factanal(x = data, factors = 2, covmat = matrix, :
requested scores without
2010 Nov 19
4
calculating martingale residual on new data using "predict.coxph"
Hi list,
I was trying to use "predict.coxph" to calculate martingale residuals on a test
data, however, as pointed out before
http://tolstoy.newcastle.edu.au/R/e4/help/08/06/13508.html
predict(mycox1, newdata, type="expected") is not implemented yet. Dieter
suggested to use 'cph' and 'predict.Design', but from my reading so far, I'm not
sure they can
2010 Nov 11
2
predict.coxph and predict.survreg
Dear all,
I'm struggling with predicting "expected time until death" for a coxph and
survreg model.
I have two datasets. Dataset 1 includes a certain number of people for which
I know a vector of covariates (age, gender, etc.) and their event times
(i.e., I know whether they have died and when if death occurred prior to the
end of the observation period). Dataset 2 includes another
2017 Sep 13
3
vcov and survival
Dear Terry,
Even the behaviour of lm() and glm() isn't entirely consistent. In both cases, singularity results in NA coefficients by default, and these are reported in the model summary and coefficient vector, but not in the coefficient covariance matrix:
----------------
> mod.lm <- lm(Employed ~ GNP + Population + I(GNP + Population),
+ data=longley)
>
2011 Apr 18
2
help with eval()
I've narrowed my scope problems with predict.coxph further.
Here is a condensed example:
fcall3 <- as.formula("time ~ age")
dfun3 <- function(dcall) {
fit <- lm(dcall, data=lung, model=FALSE)
model.frame(fit)
}
dfun3(fcall3)
The final call fails: it can't find 'dcall'.
The relevant code in model.frame.lm is:
env <- environment(formula$terms)
2011 Dec 12
1
k-folds cross validation with conditional logistic
--begin inclusion --
I have a matched-case control dataset that I'm using conditional
logistic regression (clogit in survival) to analyze. I'm trying to
conduct k-folds cross validation on my top models but all of the
packages I can find (CVbinary in DAAG, KVX) won't work with clogit
models. Is there any easy way to do this in R?
-end inclusion --
The clogit funciton is simply a
2006 Aug 11
1
- factanal scores correlated?
Hi,
I wonder why factor scores produced by factanal are correlated, and I'd
appreciate any hints from people that may help me to get a deeper
understanding why that's the case. By the way: I'm a psychologist used
to SPSS, so that question my sound a little silly to your ears.
Here's my minimal example:
***********************************************
v1 <-
2009 Aug 01
2
Cox ridge regression
Hello,
I have questions regarding penalized Cox regression using survival
package (functions coxph() and ridge()). I am using R 2.8.0 on Ubuntu
Linux and survival package version 2.35-4.
Question 1. Consider the following example from help(ridge):
> fit1 <- coxph(Surv(futime, fustat) ~ rx + ridge(age, ecog.ps, theta=1), ovarian)
As I understand, this builds a model in which `rx' is