lognormal distribution in survreg (Mariana Wagner)
On Mon, 6 Aug 2007, Lazarus Mramba wrote:
Hi Mariana, The log(scale)=0.40546 output means that if you want to get the scale, then, you compute the exponential of the coefficients 0.40546 and the answer will be 1.5
And this 1.5 is the standard deviation of a normal distribution, ie, of the log of survival time. -thomas
The sclae for the standard error can be found by computing the exponential of 0.0594, giving 1.0611996 Is that clear? Kind regards, Lazarus Mramba P.O Box 230, 80108, Kilifi, Kenya Mobile No. +254721292370 (office extension : 419)
r-sig-epi-request at stat.math.ethz.ch 08/04 1:00 PM >>>
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Thomas Lumley Assoc. Professor, Biostatistics tlumley at u.washington.edu University of Washington, Seattle