[R] differences between survival models between STATA and R

[Terry Therneau]

Without more information, we can only guess what you did, or what you 
are seeing on the page that is "different".

I'll make a random guess though.  There are about 5 ways to paramaterize 
the Weibull distribution.  The standard packages that I know, however, 
tend to use the one found in the Kalbfleisch and Prentice book The 
Statistical Analysis of Failure time Data.  This includes the survreg 
funciton in R and lifereg in SAS, and likely stata tthought I don't know 
that package.  The aftreg function in the eha package uses something 
different.

About 1/2 the weibull questions I see are due to a change in parameters.

Terry T.

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Dear Community,

I have been using two types of survival programs to analyse a data set.

The first one is an R function called aftreg. The second one an STATA
function called streg.

Both of them include the same analyisis with a weibull distribution. Yet,
results are very different.

Shouldn't the results be the same?

Kind regards,
J