R: Classes and Methods in Package relaimpo

classesmethods.relaimpo {relaimpo} | R Documentation

## Classes and Methods in Package relaimpo

### Description

Output objects from package relaimpo have classes `relimplm` (output from calc.relimp), `relimplmboot` (output from boot.relimp), `relimplmbooteval` (output from booteval.relimp) or `relimplmbootMI`. For classes `relimplm`, `relimplmbooteval` and `relimplmbootMI`, there are methods for plotting and printing, usage of which is described below. For class `relimplmbootMI`, there is in addition a summary-method, which produces a less detailed output than the show / print - method. For classes `relimplm`, `relimplmbooteval` and `relimplmbootMI`, there is in addition a method for extracting slots of the class with \$.

### Usage

    ## S3 method for class 'relimplm'
    print(x,...,show.coeffs = ifelse(any(c("lmg", "pmvd") %in% x@type)
        & is.null(x@always), TRUE, FALSE))

    ## S3 method for class 'relimplm'
    plot(x,...,names.abbrev=4, ylim=NULL, main=NULL, cex.title=1.5)

    ## S3 method for class 'relimplmbooteval'
    print(x,...)

    ## S3 method for class 'relimplmbootMI'
    print(x,...)

    ## S3 method for class 'relimplmbooteval'
    plot(x, ..., lev=max(x@level), names.abbrev=4, ylim=NULL,
        main=NULL, cex.title=1.5)

    ## S3 method for class 'relimplmbootMI'
    plot(x, ..., lev=max(x@level), names.abbrev=4, ylim=NULL,
        main=NULL, cex.title=1.5)

    ## S3 method for class 'relimplmbootMI'
    summary(object, ..., lev = max(object@level))

### Arguments

`x` | `x` is an output object from package relaimpo of the required class
`show.coeffs` | `show.coeffs`, if set to `FALSE`, suppresses printing of averaged coefficients, which are otherwise printed, if `lmg` and/or `pmvd` are among the metrics in `x` and `always` is `NULL`. See details for a discussion of the averaged coefficients, if `always` is not `NULL`.
`object` | `object` is an object of class `relimplmbootMI` (output from function `mianalyze.relimp`)
`...` | further arguments to functions
`names.abbrev` | `names.abbrev` is an integer that provides the number of characters to which the bar labels are shortened (default: 4).
`ylim` | The plot routines try to use appropriate scaling. If adjustments are needed, `ylim` can be used like usually on plot.
`main` | The plot routine uses a default title based on the reponses name. If adjustments are desired, `main` can be used for specifying a different title. Note that only the first title is affected (in case of plot.relimpbooteval, there is also a sub title that cannot be changed).
`cex.title` | `cex.title` specifies the text size for the overall title. Thus, the `par` option `cex.main` can be used for specifying the size of individual plot titles.
`lev` | `lev` is a numeric that provides the confidence level to be plotted or displayed respectivly (default: maximum available confidence level; 0.5<lev<1 ).

### Details

This documentation part describes S3 methods. In addition there are S4 methods for `show` which coincide with the S3 methods for `print` and an S4 method for coercing objects of `relimplm` to lists (of their numeric elements).

Print (and show) methods produce annotated output for `calc.relimp`, `booteval.relimp`, and `mianalyze.relimp` (or the objects produced by these functions). Since version 2.1, `calc.relimp` provides averaged coefficients for different sub model sizes (slot `ave.coeffs` of class `relimplm`), if metrics based on averaging over orderings (`lmg` and/or `pmvd`) are calculated. These are per default printed if the slot `always` of `x` is `NULL`. If some variables were forced into all models (non-NULL `always`), the averaged coefficients refer to the adjusted model after taking residuls from regressions on the `always`-columns of the X-matrix for both response and the other columns of the X-matrix. The reason is that these could be easily and cheaply implemented into the existing code and do correspond to sub models relevant for `lmg` and `pmvd`. Users who are interested in these coefficients, can set option `show.coeffs=TRUE` in spite of non-NULL `always`.

The plot methods produce barplots of relative contributions, either of the metrics alone for output objects of class `relimplm` from function `calc.relimp`, or of the metrics with lines indicating confidence intervals for output objects of class `relimplmbooteval` from function `booteval.relimp` or `relimplmbootMI` from function `booteval.relimp`.

Most `par()` options can be set and should work on plot. Exceptions: mfrow, oma and mar are set by the plot function, depending on the number of metrics to plot and the amount of annotating text required.

The summary-method for class `relimplmbootMI` allows to quickly display brief output and to change the confidence level versus the level used in the original run (with interval bounds stored in the “metric”.lower and “metric”.upper slots and displayed by print and show methods).

Because of a defined S3-extraction method, slots of classes `relimplm`, `relimplmbooteval` and `relimplmbootMI` can be extracted not only with the @ extractor but also with \$. Hence, output elements from functions `calc.relimp`, `booteval.relimp`, and `mianalyze.relimp` can be extracted as though the output objects were lists.

Note that there also is an an internally-used class relimplmtest that permits the internal function calc.relimp.default.intern to output further detail needed for usage from within other funtions.

### Author(s)

Ulrike Groemping, BHT Berlin

### References

Go to http://prof.tfh-berlin.de/groemping/ for further information and references.

### See Also

relaimpo, `calc.relimp`, `booteval.relimp`, `mianalyze.relimp`, `relimplm-class`, `relimplmboot-class`, `relimplmbooteval-class`, `relimplmbootMI-class`

[Package relaimpo version 2.2-2 Index]