Displaying 20 results from an estimated 500 matches similar to: "looping survdiff?"
2012 Oct 19
1
Looping survdiff
The number of recent questions from umn.edu makes me wonder if there's homework involved....
Simpler for your example is to use get and subset.
dat <- structure(..... as found below
var.to.test <- names(dat)[4:6] #variables of interest
nvar <- length(var.to.test)
chisq <- double(nvar)
for (i in 1:nvar) {
tfit <- survdiff(Surv(time, completion==2) ~
2007 Apr 26
2
Extract p-value from survdiff function
Hi list,
I want to use the p-value from the survdiff function (package
survival) to reuse within a function in a Kaplan-Meier plot. The
p-value is somehow not a component of the value list ?!
Thanks in advance
--
A. Goralczyk
G?ttingen, Ger.
2012 Oct 19
2
Question about survdiff in for-loop.
Hi everyone!!
I have dataset composed of a numbers of survival analyses.
( for batch survival analyses by using for-loop) .
Here are code !!
#######
dim(svsv)
Num_t<-dim(svsv)
Num<-Num_t[2] # These are predictors !!
names=colnames(svsv)
for (i in 1:Num )
{
name_tt=names[i]
survdiff(Surv(survival.m, survival) ~ names[i], data=svsv)
fit.Group<-survfit(Surv(survival.m, survival) ~
2008 Dec 04
1
Comparing survival curves with "survdiff" "strata" help
ExpeRts,
I'm trying to compare three survival curves using the function "survdiff" in the survival package. Following is my code and corresponding error message.
> survdiff(Surv(st_months, status) ~ strata(BOR), data=mydata)
Error in survdiff(Surv(st_months, status) ~ strata(BOR), data = mydata) :
No groups to test
When I check the "strata" of the variable. I get .
2012 Oct 17
2
loop of quartile groups
Greetings R users,
My goal is to generate quartile groups of each variable in my data set. I
would like each experiment to have its designated group added as a
subsequent column. I can accomplish this individually with the following
code:
brks <- with(data_variables,
cut2(var2, g=4))
#I don't want the actual numbers, I need a numbered group
data$test1=factor(brks,
2009 Sep 16
2
Teasing out logrank differences *between* groups using survdiff or something else?
R Folk:
Please forgive what I'm sure is a fairly na?ve question; I hope it's clear.
A colleague and I have been doing a really simple one-off survival analysis,
but this is an area with which we are not very familiar, we just happen to
have gathered some data that needs this type of analysis. We've done quite
a bit of reading, but answers escape us, even though the question below
2001 Nov 22
1
p-value using survdiff
Dear all,
Does anyone knows how I could extract the p-value in:
> survdiff(Surv(tempo,status) ~ grupo,data=dados1,rho=1)
Call:
survdiff(formula = Surv(tempo, status) ~ grupo, data = dados1, rho = 1)
N Observed Expected (O-E)^2/E (O-E)^2/V
grupo=1 21 5.12 12.00 3.94 14.5
grupo=2 21 14.55 7.68 6.16 14.5
Chisq= 14.5 on 1 degrees of freedom,
2010 Jul 07
1
Appropriateness of survdiff {survival} for non-censored data
I read through Harrington and Fleming (1982) but it is beyond my
statistical comprehension. I have survival data for insects that have
a very finite expiration date. I'm trying to test for differences in
survival distributions between different groups. I understand that
the medical field is most often dealing with censored data and that
survival analysis, at least in the package survival,
2005 Nov 23
1
survdiff for Left-truncated and right-censored data
dear all,
I would like to know whether survdiff and survReg function in the
survival package work for left-truncated and right-censored data.
If not, what other functions can i use to make comparison between two
survival curves with LTRC data.
thanks for any help given
sing yee
2013 Apr 29
3
Comparing two different 'survival' events for the same subject using survdiff?
I have a dataset which for the sake of simplicity has two endpoints. We would like to test if two different end-points have the same eventual meaning. To try and take an example that people might understand better:
Lets assume we had a group of subjects who all received a treatment. The could stop treatment for any reason (side effects, treatment stops working etc). Getting that data is very
2009 Aug 03
1
survdiff for left-truncated data?
Hi
Does anyone know if there is a function like survdiff which can also handle
left-truncated and right-censored data? When I use it on left-truncated and
right-censored data I get an error message saying Right censored data only.
Many thanks
Rajen
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2004 Aug 17
1
survdiff
Hello,
As I am quitte an ignorant user of R, excuse me for any wrongfull usage of
all the terms.
My question relates to the statistics behind the survdiff function in the
package survival.
My textbook knowledge of the logrank test tells me that if I want to compare
two survival curves, I have to take the sum of the factors: (O-E)^2/E of
both groups, which will give me the Chisq.
If I calculate
2011 Jul 21
0
Survdiff for multiple comparisons
Hello all-
I am doing a survival analysis for two species of invasive plants I
outplanted to edges and interiors of island and mainland sites in a local
reservoir. I am using the KM estimate and had no problem doing survdiff for
my data using the following code:
S4<-Surv(outplant$SurvTime, outplant$StatusD6)
diff4=survdiff(S4 ~ outplant$Species+outplant$SiteType+outplant$EdgInt)
diff4
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
2018 Feb 14
2
Fleming-Harrington weighted log rank test
Hi all,?
The survdiff() from survival package has an argument "rho" that implements Fleming-Harrington weighted long rank test.?
But according to several sources including "survminer" package (https://cran.r-project.org/web/packages/survminer/vignettes/Specifiying_weights_in_log-rank_comparisons.html), Fleming-Harrington weighted log-rank test should have 2 parameters
2012 Feb 23
2
Survival analysis and comparing survival curves
Hei,
I have a one simple question which does not seem to be that simple as I
cannot find any solution/answer:
Is it possible to compare multiple survival curves in R with
survdiff-function when there is interaction term involved in predictor
variables (and this interaction is significant)?
Example:
survdiff(Surv(death,status)~treatment*gapsize)
R is making "problems" with it ie.e.
2012 Jan 26
2
extracting from data.frames for survival analysis
Hi,
I have a data frame:
> class(B27.vec)
[1] "data.frame"
> head(B27.vec)
AGE Gend B27 AgeOn DD uveitis psoriasis IBD CD UC InI BASDAI BASFI Smok UV
1 57 1 1 19 38 2 1 1 1 1 1 5.40 8.08 NA 1
2 35 1 1 33 2 2 1 1 1 1 1 1.69 2.28 NA 1
3 49 2 1 40 9 1 1 1 1 1 1 8.30 9.40 NA
2007 May 01
7
logrank test
how do l programme the logrank test. l am trying to compare 2 survival curves
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2018 Feb 15
0
Fleming-Harrington weighted log rank test
> On Feb 13, 2018, at 4:02 PM, array chip via R-help <r-help at r-project.org> wrote:
>
> Hi all,
>
> The survdiff() from survival package has an argument "rho" that implements Fleming-Harrington weighted long rank test.
>
> But according to several sources including "survminer" package
2018 Feb 15
1
Fleming-Harrington weighted log rank test
> On Feb 14, 2018, at 5:26 PM, David Winsemius <dwinsemius at comcast.net> wrote:
>
>>
>> On Feb 13, 2018, at 4:02 PM, array chip via R-help <r-help at r-project.org> wrote:
>>
>> Hi all,
>>
>> The survdiff() from survival package has an argument "rho" that implements Fleming-Harrington weighted long rank test.
>>