\begin{Schunk}
\begin{Sinput}
 set.seed(234234)
 N <- 25; stde <- 2; b <- 0.14
 x <- rnorm(N, m=50, sd=10)
 x <- x[order(x)]
 y <- 0.3 + b*x + rnorm(N, m=0, sd=stde)
 mx <- round(mean(x),2)
 my <- round(mean(y),2)
 rx <- range(x)
 ry <- range(y)
 cov(x,y)
\end{Sinput}
\begin{Soutput}
[1] 13.17417
\end{Soutput}
\begin{Sinput}
 plot(x,y, main="")
\end{Sinput}
\end{Schunk}
