I uses the Design library.

take this example:

library(Design)
n <- 1000
set.seed(731)
age <- 50 + 12*rnorm(n)
label(age) <- "Age"
sex <- factor(sample(c('Male','Female'), n,
              rep=TRUE, prob=c(.6, .4)))
cens <- 15*runif(n)
h <- .02*exp(.04*(age-50)+.8*(sex=='Female'))
dt <- -log(runif(n))/h
label(dt) <- 'Follow-up Time'
e <- ifelse(dt <= cens,1,0)
dt <- pmin(dt, cens)
units(dt) <- "Year"
dd <- datadist(age, sex)
options(datadist='dd')
Srv <- Surv(dt,e)

f <- cph(Srv ~ rcs(age,4) + sex, x=TRUE, y=TRUE)
cox.zph(f, "rank")             # tests of PH
anova(f)
# Error in anova.Design(f) : could not find function "Varcov"



Yao Zhu
Department of Urology
Fudan University Shanghai Cancer Center
No. 270 Dongan Road, Shanghai, China


2009/9/12 Ronggui Huang <ronggui.huang@gmail.com>

> I cannot reproduce the problem you mentioned.
>
> >  ctl <- c(4.17,5.58,5.18,6.11,4.50,4.61,5.17,4.53,5.33,5.14)
> >  trt <- c(4.81,4.17,4.41,3.59,5.87,3.83,6.03,4.89,4.32,4.69)
> >   group <- gl(2,10,20, labels=c("Ctl","Trt"))
> >   weight <- c(ctl, trt)
> >   anova(lm.D9 <- lm(weight ~ group))
> > sessionInfo()
> R version 2.9.2 (2009-08-24)
> i386-pc-mingw32
>
> locale:
> LC_COLLATE=Chinese (Simplified)_People's Republic of
> China.936;LC_CTYPE=Chinese (Simplified)_People's Republic of
> China.936;LC_MONETARY=Chinese (Simplified)_People's Republic of
> China.936;LC_NUMERIC=C;LC_TIME=Chinese (Simplified)_People's Republic
> of China.936
>
> attached base packages:
> [1] stats     graphics  grDevices utils     datasets  methods   base
>
> 2009/9/12 zhu yao <mailzhuyao@gmail.com>:
> > After upgrading R to 2.9.2, I can't use the anova() fuction.
> > It says "could not find function "Varcov" ".
> > What's wrong with my computer? Help needed, thanks!
> >
> > Yao Zhu
> > Department of Urology
> > Fudan University Shanghai Cancer Center
> > No. 270 Dongan Road, Shanghai, China
> >
> >        [[alternative HTML version deleted]]
> >
> > ______________________________________________
> > R-help@r-project.org mailing list
> > https://stat.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> > and provide commented, minimal, self-contained, reproducible code.
> >
>
>
>
> --
> HUANG Ronggui, Wincent
> Doctoral Candidate
> Dept of Public and Social Administration
> City University of Hong Kong
> Home page: http://asrr.r-forge.r-project.org/rghuang.html
>

	[[alternative HTML version deleted]]


