\documentclass[11pt]{article}
\title{My First Sweave Document}
\begin{document}
\maketitle

\section{Introduction}
This is some text (i.e. a ``text chunk'').   
Here is a code chunk but it doesn't print anything!
<<simulation,echo=false,results=hide>>=
x <- rnorm(100); y <- x + rnorm(100, sd = 0.5)
mean(x)
@
\end{document}