Cox model fitting functions
agreg.fit.RdThese 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.
Usage
agreg.fit(x, y, strata, offset, init, control, weights, method,
rownames, resid=TRUE, nocenter=NULL)
coxph.fit(x, y, strata, offset, init, control, weights, method,
rownames, resid=TRUE, nocenter=NULL)Arguments
- x
Matix of predictors. This should not include an intercept.
- y
a
Survobject containing either 2 columns (coxph.fit) or 3 columns (agreg.fit).- strata
a vector containing the stratification, or NULL
- offset
optional offset vector
- init
initial values for the coefficients
- control
the result of a call to
coxph.control- weights
optional vector of weights
- method
method for handling ties, one of "breslow" or "efron"
- rownames
this is only needed for a NULL model, in which case it contains the rownames (if any) of the original data.
- resid
compute and return residuals.
- nocenter
an optional list of values. Any column of the X matrix whose values lie strictly within that set will not be recentered. Note that the coxph function has (-1, 0, 1) as the default.
Details
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.