[R] a question

array chip
Fri, 05 Aug 2011 18:19:51 -0000

Hi, I read on a paper the below statement, don't know how that was
calculated. Basically, there are 2 continuous variables x1 and x2, as
independent variable for predicting cancer recurrence. So this is a survival
analysis. Now the author try to check the correlation between x1 and x2. He
calculated Spearman rand correlation (~0.22), then he had the following
statement:

"Only approximately 5% of the variability in the estimates of recurrence
using either of these scores was explained by the other".

How was that done? with a Cox model including both x1 and x2, can we get that
number (5%)?

Thanks for any hints

John