\begin{Schunk}
\begin{Sinput}
     summary(dat)
\end{Sinput}
\begin{Soutput}
      grp          ed             inc        mar    sex    
 Min.   :1   Min.   : 6.00   Min.   :11112   N:9   Fem: 9  
 1st Qu.:1   1st Qu.: 9.50   1st Qu.:23172   W:1   Mal:10  
 Median :2   Median :12.00   Median :34333   Y:9           
 Mean   :2   Mean   :12.37   Mean   :38764                 
 3rd Qu.:3   3rd Qu.:14.50   3rd Qu.:44394                 
 Max.   :3   Max.   :20.00   Max.   :78787                 
\end{Soutput}
\end{Schunk}
