\usepackage {pstricks,pst-node}
\begin{pspicture}(0,0)(2.5,5)
\begin{psmatrix}[rowsep=1.5cm]
               & City  &\\
 {\tiny Shack} & House & {\Large Hotel}
 \psset{arrows=<<-}
 \ncline{1,2}{2,1}<{a}
 \ncline{1,2}{2,2}>{b}
 \ncline{1,2}{2,3}>{b}
 \psset{arrows=-,linestyle=dotted}
 \ncline{2,1}{2,2}
 \ncline{2,2}{2,3}
\end{psmatrix}
\end{pspicture}
