Displaying 20 results from an estimated 500 matches similar to: "Possible bug in summary.survfit - 'scale' argument ignored?"
2011 Jul 10
1
Package "survival" --- Difference of coxph strata with subset?
[code]>require("survival")
> coxph(Surv(futime,fustat)~age + strata(rx),ovarian)
Call:
coxph(formula = Surv(futime, fustat) ~ age + strata(rx), data = ovarian)
coef exp(coef) se(coef) z p
age 0.137 1.15 0.0474 2.9 0.0038
Likelihood ratio test=12.7 on 1 df, p=0.000368 n= 26, number of events= 12
> coxph(Surv(futime,fustat)~age, ovarian, subset=rx==1)
2011 Jan 20
1
Problems with ecodist
Dear Dr.Goslee and anyone may intrested in matrix manipulate,
I am using your ecodist to do mantel and partial mantel test, I have
locality data and shape variation data, and the two distance matrixs are
given as belowings. When I run the analysis, it is always report that the
matrix is not square, but I didn't know what's wrong with my data. Would you
please help me on this. I am quite
2020 Sep 30
0
2 KM curves on the same plot
Hi John,
Brilliant solution and the best sort - when you finally solve your
problem by yourself.
Jim
On Thu, Oct 1, 2020 at 2:52 AM array chip <arrayprofile at yahoo.com> wrote:
>
> Hi Jim,
>
> I found out why clip() does not work with lines(survfit.object)!
>
> If you look at code of function survival:::lines.survfit, in th middle of the code:
>
> do.clip <-
2012 Jun 28
3
Sobre survival analysis
Hola
Estoy tratando de correr un survival analysis usando un Cox regression model.
Tengo una duda respecto a la organizacion del script. Tengo una variable que es -tamano del individuo- y quiero ver si hay diferencia en sobrevivencia respecto a tamano. Como diseno de campo los tamanos fueron ubicados de forma aleatoria en bloques al azar.
Cuado planteo el script tengo algo como:
2009 Nov 13
2
survreg function in survival package
Hi,
Is it normal to get intercept in the list of covariates in the output of survreg function with standard error, z, p.value etc? Does it mean that intercept was fitted with the covariates? Does Value column represent coefficients or some thing else?
Regards,
-------------------------------------------------
tmp = survreg(Surv(futime, fustat) ~ ecog.ps + rx, ovarian,
2018 May 24
1
Predictions from a Cox model - understanding centering of binary/categorical variables
Dear all,
I am using R 3.4.3 on Windows 10. I am preparing some teaching materials and I'm having trouble matching the by-hand version with the R code.
I have fitted a Cox model - let's use the ovarian data as an example:
library(survival)
data(ovarian)
ova_mod <- coxph(Surv(futime,fustat)~age+rx,data=ovarian)
If I want to make predict survival for a new set of individuals at 100
2007 Jan 23
1
Estimate and plot hazard function using "muhaz" package
Dear R users,
I am trying to use "muhaz" and "plot.muhaz" functions in "muhaz" package to
estimate and plot hazard funciton. However function "muhaz" always gives
error message "Error in Surv(times, delta) : object "times" not found". I
could not even run their sample codes in the user's manual as follows:
data(ovarian)
2009 Feb 06
1
Using subset in validate() in Design, what is the correct syntax?
Hi
I am trying to understand how to get the validate() function in Design
to work with the subset option. I tried this:
ovarian.cph=cph(Surv(futime, fustat) ~ age+factor(ecog.ps)+strat(rx),
time.inc=1000, x=T, y=T, data=ovarian)
validate(ovarian.cph)
#fine when no subset is used, but the following two don't work:
> validate(ovarian.cph, subset=ovarian$ecog.ps==2)
Error in
2005 Nov 27
1
the output of coxph
Dear All:
I have some questions about the output of coxph.
Below is the input and output:
----------------------------------------
> coxph(formula = Surv(futime, fustat) ~ age + rx + ecog.ps, data =
+ ovarian, x = TRUE)
Call:
coxph(formula = Surv(futime, fustat) ~ age + rx + ecog.ps, data =
ovarian, x = TRUE)
coef exp(coef) se(coef) z p
age 0.147 1.158
2011 Jun 24
1
UnoC function in survAUC for censoring-adjusted C-index
Hello,
I am having some trouble with the 'censoring-adjusted C-index' by Uno et al, in the package survAUC. The relevant function is UnoC.
The question has to do with what happens when I specify a time point t for the upper limit of the time range under consideration (we want to avoid using the right-end tail of the KM curve).
Copying from the example in the help file:
TR <-
2009 Apr 14
1
Function call error in cph/survest (package Design)
Dear UseR,
I do not know if this a problem with me, my data or cph/survest in package
design. The example below works with a standard data set, but not with my
data, but I cannot locate the problem.
Note that I am using an older package of survival to avoid a problem with
the newly renamed function in survival meeting Design.
Dieter
# First, check standard example to make sure
library(Design)
2007 May 16
2
log rank test p value
How can I get the Log - Rank p value to be output?
The chi square value can be output, so I was thinking if I can also have the
degrees of freedom output I could generate the p value, but can't see how to
find df either.
> (survtest <- survdiff(Surv(time, cens) ~ group, data = surv,rho=0))
Call:
survdiff(formula = Surv(time, cens) ~ group, data = surv, rho = 0)
N Observed
2010 Oct 30
1
two group cox model
Dear all,
I am doing
library(survival)
fit <- coxph(Surv(futime,fustat) ~ rx, ovarian)
plot(survfit(fit,newdata=ovarian),col=c(1,2))
legend("bottomleft", legend=c("rx = 0", "rx = 1"),
lty=c(1,2),col=c(1,2))
Is this correct to compare these two groups? Is the 0.31 the p-value that
the median f two groups are equal
Why lty does not work here?
Many thanks
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
2007 Dec 07
1
Make natural splines constant outside boundary
Hi,
I'm using natural cubic splines from splines::ns() in survival
regression (regressing inter-arrival times of patients to a queue on
queue size). The queue size fluctuates between 3600 and 3900.
I would like to be able to run predict.survreg() for sizes <3600 and
>3900 by assuming that the rate for <3600 is the same as for 3600 and
that for >4000 it's the same as for
2009 Feb 23
1
why results from regression tree (rpart) are totally inconsistent with ordinary regression
Hi,
In my analysis of impacts of insecticide-treated bednets on malaria, I
look at the relationship between malaria incidence and mosquito
behaviors. The condensed data set is copied here. Ordinary regression
(lm) shows that Incidence was negatively related to Mortality. This
makes sense because the latter reflected the strength of killing
mosquitoes by insecticide-treated nets. Since the
2008 Sep 05
1
Plot by column
Dear list,
I have the following matrix. How can I make the following plot?
1. The x-axis has index 1:7, and the first column is plotted against index 1, second against 2, and so on.
2. I want the points from the left upper conner including the antidiagonal to be plotted with col=2, and the rest with col=3
[,1] [,2] [,3] [,4] [,5] [,6] [,7]
[1,] 0.589 0.857 0.923 0.944 0.954 0.963
2011 Oct 01
4
Is the output of survfit.coxph survival or baseline survival?
Dear all,
I am confused with the output of survfit.coxph.
Someone said that the survival given by summary(survfit.coxph) is the
baseline survival S_0, but some said that is the survival S=S_0^exp{beta*x}.
Which one is correct?
By the way, if I use "newdata=" in the survfit, does that mean the survival
is estimated by the value of covariates in the new data frame?
Thank you very much!
2006 Dec 21
1
: newbie estimating survival curve w/ survfit for coxph
I am wondering how to estimate the survival curve for a particular case(s)
given a coxph model
using this example code:
#fit a cox proportional hazards model and plot the
#predicted survival curve
fit <- coxph(
Surv(futime,fustat)~resid.ds+strata(rx)+ecog.ps+age,data=ovarian[1:23,])
z <- survfit(fit,newdata=ovarian[24:26,],individual=F)
zs <- z$surv
zt <-
2010 Feb 16
1
survival - ratio likelihood for ridge coxph()
It seems to me that R returns the unpenalized log-likelihood for the ratio likelihood test when ridge regression Cox proportional model is implemented. Is this as expected?
In the example below, if I am not mistaken, fit$loglik[2] is unpenalized log-likelihood for the final estimates of coefficients. I would expect to get the penalized log-likelihood. I would like to check if this is as expected.