Many thanks for your question that I did not dare asking and for the instructive responses. Another example of plotting hazard can be found in Retsky M et al, breast cancer research: http://breast-ca
I would like to test the joint significance of two variables (V2, V3) in a Cox model with three variables V1, V2, V3. Is it ok to do: fit <- coxph(Surv(time,event) ~ V1, data=m) update(fit, ~ . + V2
Hello, I'm new on the list - had the same question a few days ago - would appreciate if you place a summary of the solutions on the list. Vincent Vinh-Hung
I agree -- as a beginner I find the question was not trivial -- and in principle if a question arises, then something is not trivial -- and I'm always glad to see a summary, or a pointer to where one
I would like to select rows from a table that have at least, say, 3 duplicates. X Y 1 1 a 2 1 b 3 4 c 4 3 d 5 2 e 6 3 f 7 1 g Command tabulate seems to do the job: X Y 1 1 a 2 1 b 7 1 g But tabulate
Many thanks to David Lorenz who suggested do.call Bill Dunlap who suggested table() more general than tabulate. David Pollard's web site also provided an example adaptable as: m$Y[match(m$X,names(tab