R: Number of Parameters

nparam.vlm {VGAM} | R Documentation

## Number of Parameters

### Description

Returns the number of parameters in a fitted model object.

### Usage

            nparam(object, ...)
        nparam.vlm(object, dpar = TRUE, ...)
       nparam.vgam(object, dpar = TRUE, linear.only = FALSE, ...)
     nparam.rrvglm(object, dpar = TRUE, ...)
    nparam.qrrvglm(object, dpar = TRUE, ...)
     nparam.rrvgam(object, dpar = TRUE, ...)

### Arguments

`object` | Some VGAM object, for example, having class `vglmff-class`.
`...` | Other possible arguments fed into the function.
`dpar` | Logical, include any (estimated) dispersion parameters as a parameter?
`linear.only` | Logical, include only the number of linear (parametric) parameters?

### Details

The code was copied from the `AIC()` methods functions.

### Value

Returns a numeric value with the corresponding number of parameters. For `vgam` objects, this may be real rather than integer, because the nonlinear degrees of freedom is real-valued.

### Warning

This code has not been double-checked.

### Author(s)

T. W. Yee.

### See Also

VGLMs are described in `vglm-class`; VGAMs are described in `vgam-class`; RR-VGLMs are described in `rrvglm-class`; `AICvlm`.

### Examples

    pneumo <- transform(pneumo, let = log(exposure.time))
    (fit1 <- vglm(cbind(normal, mild, severe) ~ let, propodds, data = pneumo))
    coef(fit1)
    coef(fit1, matrix = TRUE)
    nparam(fit1)
    (fit2 <- vglm(hits ~ 1, quasipoissonff, weights = ofreq, data = V1))
    coef(fit2)
    coef(fit2, matrix = TRUE)
    nparam(fit2)
    nparam(fit2, dpar = FALSE)

[Package VGAM version 1.0-3 Index]