rlm.R

library(MASS)

N <- 60
x <- rep(c('a', 'b'), N)
x_dummy <- as.numeric(x == 'a')

y <- x_dummy + rt(N, 2)

data <- data.frame(x = x, y = y)

boxplot(y ~ x, data)


m1 <- lm(y ~ x, data = data)
plot(m1)


m2 <- rlm(y ~ x, data = data)
plot(m2) # residual vs leverage plot looks ok.