\documentclass{article}
\usepackage{com.braju.graphicalmodels}
\usepackage{amsmath}
% \special{papersize=40mm,80mm}
% \setlength{\pdfpagewidth}{40mm}
% \setlength{\pdfpageheight}{80mm}
% \usepackage[vcentering,dvips]{geometry}
% \geometry{papersize={80mm,120mm},total={80mm,120mm},margin=0mm}



\catcode`\@=11%

\pagestyle{empty}

\begin{document}
\TeXtoEPS

\LARGE
\psset{unit=10mm,arrowscale=1.5,linewidth=1.5pt}

\begin{pspicture}(0,0)(10,5)
  \SpecialCoor

  \rput(1,1){\rnode{x_i}{$\boldsymbol{x}_i$}}
  \rput(1,3){\rnode{w}{$\boldsymbol{w}$}}
  \rput(3,2){\rnode{eta_i}{$\eta_i$}}
  \rput(6,2){\rnode{mu_i}{$\mu_i$}}       
  \rput(9,2){\rnode{theta_i}{$\theta_i$}}       
       
  \psset{arrows=->,nodesep=5pt}
  \ncline{w}{eta_i}
  \ncline{x_i}{eta_i}
  \psset{offset=4pt}
  \ncline{eta_i}{mu_i}
  \naput{$g^{-1}$}
  \ncline{mu_i}{eta_i}
  \naput{$g$}
  \ncline{mu_i}{theta_i}
  \naput{$\Psi$}
  \ncline{theta_i}{mu_i}
  \naput{$\Psi^{-1}$}
       
\end{pspicture}

\endTeXtoEPS
\end{document}