\begin{Schunk}
\begin{Sinput}
  dat$grpfac3 <- dat$grpfac2
  levels(dat$grpfac3) <- c("Midwest","Western","Eastern")
  str(dat$grpfac3)
\end{Sinput}
\begin{Soutput}
 Factor w/ 3 levels "Midwest","Western",..: 2 1 2 3 2 2 1 1 1 2 ...
\end{Soutput}
\begin{Sinput}
  with(dat, table(grpfac3, grpfac2))
\end{Sinput}
\begin{Soutput}
         grpfac2
grpfac3   Western Midwest Eastern
  Midwest       7       0       0
  Western       0       6       0
  Eastern       0       0       6
\end{Soutput}
\end{Schunk}
