\listfiles
\documentclass{jarticle}
\usepackage{multirow}

\begin{document}

\newcommand{\B}{$\bullet$}
\setlength{\doublerulesep}{.9\arrayrulewidth}
\addtolength{\tabcolsep}{2pt}
\begin{tabular}{|cl||c|c||c|}
\hline
  &   & \multicolumn{2}{c||}{Y}  & \\
  &   & 0  & 1  & \\
\hline
\hline
  & 0 & n(0,0) & n(0,1) & n(0,\B) \\
\cline{2-5}
\multirow{-2}{*}{X} & 1 & n(1,0) & n(1,1) & n(1,\B) \\
\hline
\hline
  &   &  n(\B,0)   &  n(\B,1)   & n \\
\hline
\end{tabular}

\end{document}
