R: Cox model fitting functions

agreg.fit {survival} | R Documentation

## Cox model fitting functions

### Description

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.

### Usage

    agreg.fit(x, y, strata, offset, init, control, weights, method,
    rownames, resid=TRUE)
    coxph.fit(x, y, strata, offset, init, control, weights, method,
    rownames, resid=TRUE)

### Arguments

`x` | Matix of predictors. This should not include an intercept.
`y` | a `Surv` object 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 hanling 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.

### 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.

### Value

a list containing results of the fit

### Author(s)

Terry Therneau

### See Also

`coxph`

[Package survival version 3.2-7 Index]