\begin{psmatrix}[rowsep=1.5cm]
&City&\\
{\tiny Shack} & House & {\Large Hotel}
\psset{arrows=<<-}
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\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}