npelVIF: Compute the variable inflation factor of the terms in a...

In henkelstone/NPEL.Classification: Classifaction and data-handling routines for NPEL Caribou Project

Description

Given an input dataset, this function generates the VIF for each predictor variable. It gives considerably more output than the typical VIF function—see details.

Usage

npelVIF(fx, data)

Arguments

fx	a formula for which to test the VIF
data	a data frame with columns corresponding to the formula

Details

The function returns a named list of several details from the computation of the VIF scores :

• vif the resulting VIF scores for each term in the model.

• rSquared the resulting R-square with that term removed from the model.

• est a matrix of parameter estimates from each linear model. Rows are for each parameter that was estimated, and columns are the parameter estimates. Note that the parameter that is being estimated is represented by NA in the estimates since it was not included in the model.

• stdErr a matrix of the standard error for each parameter estimate in each model; the format is the same as for est.

• t.value the t.value for each parameter estimate in each model; the format is the same as for est.

• p.value the p.value for each parameter estimate in each model; the format is the same as for est.

Value

a list with the following elements: list (vif, rSquared, est, stdErr, t.value, p.value). See Details

Examples

data (siteData)
npelVIF(formula('Ecotype ~ brtns+grnns+wetns+dem+slp+asp+hsd'),siteData)

henkelstone/NPEL.Classification documentation built on May 17, 2019, 3:42 p.m.