robust (version 0.4-18.2)

anova.lmRob: ANOVA for Robust Linear Model Fits

Description

Compute an analysis of variance table for one or more robust linear model fits.

Usage

# S3 method for lmRob
anova(object, ..., test = c("RF", "RWald"))
# S3 method for lmRoblist
anova(object, const, ipsi, yc, test = c("RWald", "RF"), ...)

Arguments

object

an lmRob object.

…

additional arguments required by the generic anova function. If … contains additional robustly fitted linear models then the function anova.lmRoblist is dispatched.

const

a numeric value containing the tuning constant.

ipsi

an integer value specifying the psi-function.

yc

a numeric value containing the tuning constant.

test

a single character value specifying which test should be computed in the Anova table. The possible choices are "RWald" and "RF".

Value

an anova object.

Details

The default test used by anova is the "RWald" test, which is the Wald test based on robust estimates of the coefficients and covariance matrix. If test is "RF", the robustified F-test is used instead.

References

Hampel, F. R., Ronchetti, E. M., Rousseeuw, P. J., and Stahel, W. A. (1986). Robust statistics: the approach based on influence functions. John Wiley & Sons.

See Also

lmRob, anova.

Examples

# NOT RUN {
data(stack.dat)
stack.small <- lmRob(Loss ~ Water.Temp + Acid.Conc., data = stack.dat)
stack.full <- lmRob(Loss ~ ., data = stack.dat)
anova(stack.full)
anova(stack.full, stack.small)
# }