====== Outliers ======
<code>
install.packages("mvoutlier")
library(mvoutlier)

outliers <- aq.plot(mtcars[c("mpg","disp","hp","drat","wt","qsec")])
outliers # show list of outliers</code>
====== Normality ======
<code>
par(mfrow=c(1,1))

attach(mtcars)
qqnorm(mpg)
qqline(mpg)</code>
====== Homogeneity of Variances ======
<code># Bartlett Test of Homogeneity of Variances
bartlett.test(y~G, data=mydata)

# Figner-Killeen Test of Homogeneity of Variances
fligner.test(y~G, data=mydata)</code>