interpreting Weibull survival regression
Here gamma is the usual gamma function, see ?gamma. (I notice in the R documentation of the Weibull distribution that "E(X) = b Gamma(1+1/a)", which is an error; the G should be g (lowercase).)
It is not an error. R's function gamma() is said to implement
\eqn{\Gamma}{Gamma}: `see ?gamma'!
Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595