These are the the functions called by coxph that do the actual
computation.
In certain situations, e.g. a simulation, it may be advantageous to
call these directly rather than the usual coxph call using
a model formula.
agreg.fit(x, y, strata, offset, init, control, weights, method,
rownames, resid=TRUE, concordance=TRUE)
coxph.fit(x, y, strata, offset, init, control, weights, method,
rownames, resid=TRUE, concordance=TRUE)Matix of predictors. This should not include an intercept.
a Surv object containing either 2 columns (coxph.fit)
or 3 columns (agreg.fit).
a vector containing the stratification, or NULL
optional offset vector
initial values for the coefficients
the result of a call to coxph.control
optional vector of weights
method for hanling ties, one of "breslow" or "efron"
this is only needed for a NULL model, in which case it contains the rownames (if any) of the original data.
compute and return residuals.
compute and return the concordance.
a list containing results of the fit
This routine does no checking that arguments are the proper length or type. Only use it if you know what you are doing!
The resid and concordance arguments will save some compute
time for calling routines that only need the likelihood,
the generation of a permutation distribution for instance.