similar to: exact method in coxph

Displaying 20 results from an estimated 300 matches similar to: "exact method in coxph"

2006 Apr 26
1
help using tapply
Dear R-mates, # Here's what I am trying to do. I have a dataset like this: id = c(rep(1,8), rep(2,8)) dur1 <- c( 17,18,19,18,24,19,24,24 ) est1 <- c( rep(1,5), rep(2,3) ) dur2 <- c(1,1,3,4,8,12,13,14) est2 <- rep(1,8) mydata = data.frame(id, estat=c(est1, est2), durat=c(dur1, dur2)) # I want to one have this: id = c(rep(1,8), rep(2,8))
2010 Sep 08
4
coxph and ordinal variables?
Dear R-help members, Apologies - I am posting on behalf of a colleague, who is a little puzzled as STATA and R seem to be yielding different survival estimates for the same dataset when treating a variable as ordinal. Ordered() is used to represent an ordinal variable) I understand that R's coxph (by default) uses the Efron approximation, whereas STATA uses (by default) the Breslow. but we
2011 Jul 22
3
Cox model approximaions (was "comparing SAS and R survival....)
For time scale that are truly discrete Cox proposed the "exact partial likelihood". I call that the "exact" method and SAS calls it the "discrete" method. What we compute is precisely the same, however they use a clever algorithm which is faster. To make things even more confusing, Prentice introduced an "exact marginal likelihood" which is not
2009 Jun 15
2
Schoenfeld Residuals with tied data
Dear all, I am struggling with calculation of Schoenfeld residuals of my Cox Ph models. Based on the formula as attached, I calculated the Schoenfeld residuals for both non tied and tied data, respectively. And then I validated my results with R using the same data sets. However, I found that my results for non-tied data was ok but the results for tied data were different from R's. How
2007 Dec 12
1
Efron's locfdr package - a component missing
Hello: Could you possibly help me. In Efron's 2004 paper "Selection and Estimation ..." it was mentioned that so-called effect density estimate, denoted by g1(mu) was included in the locfdr package. However, I can't find it in the description of the package. Any suggestions? Sincerely, Nik -- View this message in context:
2006 Sep 15
2
LARS for generalized linear models
Hi, Is there an R implementation of least angle regression for binary response modeling? I know that this question has been asked before, and I am also aware of the "lasso2" package, but that only implements an L1 penalty, i.e. the Lasso approach. Madigan and Ridgeway in their discussion of Efron et al (2004) describe a LARS-type algorithm for generalized linear models. Has
2017 Nov 13
1
Bootstrap analysis from a conditional logistic regression
Nelly Reduan a partag? un fichier OneDrive avec vous. Pour l?afficher, cliquez sur le lien ci-dessous. <https://1drv.ms/u/s!Apkg2VlgfYyDgRAeVIM0nEajx0Fb> [https://r1.res.office365.com/owa/prem/images/dc-png_20.png]<https://1drv.ms/u/s!Apkg2VlgfYyDgRAeVIM0nEajx0Fb> Screenshot 2017-11-12 18.49.43.png<https://1drv.ms/u/s!Apkg2VlgfYyDgRAeVIM0nEajx0Fb> Hello How can I perform
2008 Oct 20
2
error message when plotting survival curves
I am trying to plot survival curves using the following code as an example: >rs1799964.coxph<-(coxph(Surv(sassurvmonths,status)~age+stage+rs1799964_TNFA,method="efron")) >plot(rs1799964.coxph,lyt=c(1,3),xlab="Survival in Months",ylab="Proportion Surviving") I am gettingthe following error message: >Error in xy.coords(x, y, xlabel, ylabel, log) :
2002 Aug 05
2
No subject
Hello, I downloaded R today because I was told it has very good bootstrapping abilities. What I need to do is to program it (or use an existing program) to bootstrapping test for multimodality using nonparametric kernel density estimates as proposed by Efron and Tibshirani (1993). If anyone can get me started, I will be immensely grateful. Thanks. Sangeeta
2018 Oct 02
3
maximum matrix size
I am now getting the occasional complaint about survival routines that are not able to handle big data.?? I looked in the manuals to try and update my understanding of max vector size, max matrix, max data set, etc; but it is either not there or I missed it (the latter more likely).?? Is it still .Machine$integer.max for everything??? Will that change??? Found where? I am going to need to go
2011 Sep 05
1
SAS code in R
Dear all, I was wondering if anyone can help? I am an R user but recently I have resorted to SAS to calculate the probability of the event (and the associated confidence interval) for the Cox model with combinations of risk factors. For example, suppose I have a Cox model with two binary variables, one for gender and one for treatment, I wish to calculate the probability of survival for the
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
2011 Apr 01
2
Cox Proportional Hazards model with a time-varying covariate
Hello Everyone,   I'm learning how to perform various statistical analyses in R. I'm checking my understanding by replicating examples from my SAS books. Below is an attempt to replicate a Cox Proportional Hazards model with a time-varying covariate. I think I'm doing this correctly but am not completely sure. I would appreciate it if someone could double-check my results. In case
2011 Feb 03
3
coxph fails to survfit
I have a model with quant vars only and the error message does not make sense: (mod1 <- coxph(Surv(time=strt,time2=stp,event=(resp==1))~ +incpost+I(amt/1e5)+rate+strata(termfac), subset=dt<"2010-08-30", data=inc,method="efron")) Call: coxph(formula = Surv(time = strt, time2 = stp, event = (resp == 1)) ~ +incpost + I(amt/1e+05) + rate + strata(termfac),
2007 May 21
1
Boostrap p-value in regression [indirectly related to R]
Hello All, Despite my preference for reporting confidence intervals, I need to obtain a p-value for a hypothesis test in the context of regression using bootstrapping. I have read John Fox's chapter on bootstrapping regression models and have consulted Efron & Tibshirani's "An Introduction to the Bootstrap" but I just wanted to ask the experts here for some feedback to make
2001 Mar 06
3
Bootstrapping on R
Does R have a bootstrap command like SPlus, or do we have to form our own code if we want to do bootstrapping in R? Jason Parcon Western Michigan University e-mail addresses: s0parcon at wmich.edu parcon at stat.wmich.edu -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read
2001 Mar 11
2
Doing a Cox-Regression in R and SPSS
A.S.: I am sorry for sending my first mail to <r-help at R- project.org>. --------------------------------------------------------- Hallo, computing a Cox proportional hazards model in SPSS 9.0 and R 1.2.2 produces different results for beta-coefficient. I use the follwing data set (source: example in help(coxph), somewhat modified) Time Status Covariate (x)
2008 Dec 04
1
comparing SAS and R survival analysis with time-dependent covariates
Dear R-help, I was comparing SAS (I do not know what version it is) and R (version 2.6.0 (2007-10-03) on Linux) survival analyses with time-dependent covariates. The results differed significantly so I tried to understand on a short example where I went wrong. The following example shows that even when argument 'method' in R function coxph and argument 'ties' in SAS procedure
2004 Jul 13
3
paired t-test with bootstrap
Dear Sirs, I am a R beginning user: by mean of R I would like to apply the bootstrap to my data in order to test cost differences between independent or paired samples of people affected by a certain disease. My problem is that even if I am reading the book by Efron (introduction to the bootstrap), looking at the examples in internet and available in R, learning a lot of theoretical things on
2000 Apr 09
1
Paramtric ABC
Hi, I presently working with the bootstrap methodology. I am trying to establish confidence intervals using the parametric ABC method with the bivariate normal data. I looked at the paper written by DiCiccio and Efron and did not find any programming materials which was used in that paper. So I am in confuse how to aply bootstrap ABC parametric confidence intervals method. I will be grateful to