library(MASS)

# rlm
fit <- rlm(Ozone ~ ., data=airquality)
visreg(fit, 'Wind')

# polr
fit <- polr(Sat ~ Infl + Type + Cont, weights = Freq, data = housing)
visreg(fit, 'Infl', partial=FALSE, collapse=TRUE)
visreg(fit, 'Infl', partial=FALSE, collapse=TRUE, gg=TRUE)
visreg(fit, 'Infl', partial=FALSE, collapse=TRUE, overlay=TRUE)
visreg(fit, 'Infl', type='contrast', partial=FALSE)
