R: Coefficients of Interest in a Generalized Nonlinear Model

ofInterest {gnm} | R Documentation

## Coefficients of Interest in a Generalized Nonlinear Model

### Description

Retrieve or set the `"ofInterest"` component of a `"gnm"` (generalized nonlinear model) object.

### Usage

    ofInterest(object)
    ofInterest(object) <- value

### Arguments

`object` | an object of class `"gnm"`.
`value` | a numeric vector of indices specifying the subset of (non-eliminated) coefficients of interest, or `NULL` to specify that all non-eliminated coefficients are of interest.

### Details

The `"ofInterest"` component of a `"gnm"` object is a named numeric vector of indices specifying a subset of the non-eliminated coefficients which are of specific interest.

If the `"ofInterest"` component is non-NULL, printed summaries of the model only show the coefficients of interest. In addition methods for `"gnm"` objects which may be applied to a subset of the parameters are by default applied to the coefficients of interest.

These functions provide a way of extracting and replacing the `"ofInterest"` component. The replacement function prints the replacement value to show which parameters have been specified by `value`.

### Value

A named vector of indices, or `NULL`.

### Note

Regular expression matching is performed using `grep` with default settings.

### Author(s)

Heather Turner

### See Also

`grep`, `gnm`, `se.gnm`, `getContrasts`,`profile.gnm`, `confint.gnm`

### Examples

    set.seed(1)

    ## Fit the "UNIDIFF" mobility model across education levels
    unidiff <- gnm(Freq ~ educ*orig + educ*dest +
                   Mult(Exp(educ), orig:dest),
                   ofInterest = "[.]educ", family = poisson,
                   data = yaish,  subset = (dest != 7))
    ofInterest(unidiff)

    ## Get all of the contrasts with educ1 in the UNIDIFF multipliers
    getContrasts(unidiff, ofInterest(unidiff))

    ## Get estimate and se for the contrast between educ4 and educ5 in the
    ## UNIDIFF multiplier
    mycontrast <- numeric(length(coef(unidiff)))
    mycontrast[ofInterest(unidiff)[4:5]] <- c(1, -1)
    se(unidiff, mycontrast)

[Package gnm version 1.1-2 Index]