How to extract residuals and read coefficients from the function Anova()?

Question

I use the function Anova() in package car to perform a test with type III. But I have no idea how to extract the residuals or how to get the information of parameter estimates.

Is there some way to do these like residuals(model) and summary.lm(model)?

Answer 1

The output of Anova is of class anova and data.frame.

So, if we use the extraction with row/column names, it should work. Using a reproducible example from the ?Anova documentation

library(car)
mod <- lm(conformity ~ fcategory*partner.status, data=Moore,
     contrasts=list(fcategory=contr.sum, partner.status=contr.sum))
out <- Anova(mod, type = 3)
str(out)
#Classes ‘anova’ and 'data.frame':  5 obs. of  4 variables:
# $ Sum Sq : num  5753 36 240 175 818
# $ Df     : num  1 2 1 2 39
# $ F value: num  274.359 0.859 11.425 4.185 NA
# $ Pr(>F) : num  3.05e-19 4.31e-01 1.66e-03 2.26e-02 NA
# - attr(*, "heading")= chr  "Anova Table (Type III tests)\n" "Response: conformity"

The print method changes the way how it is printing the output. But, if we just strip off the anova class. The "Residuals" are also in the row names

row.names(out)
#[1] "(Intercept)"              "fcategory"              "partner.status"           
#[4] "fcategory:partner.status" "Residuals"     

So, using the row/column names for extraction

out["Residuals","Sum Sq"]
#[1] 817.764