\usetikzlibrary{shapes.callouts}

\tikzstyle{hidden_neuron}=[circle,draw=red!50,fill=orange!10,thick,minimum size=.2mm]
\tikzstyle{input_neuron}=[circle,draw=blue!50,fill=blue!10,thick,minimum size=1mm]
\tikzstyle{output_neuron}=[circle,draw=green!50,fill=green!20,thick,minimum size=1mm]
\tikzstyle{input}=[circle,draw=black!50,fill=black!20,thick,minimum size=.2mm]
\vspace{0.3in}
\tikzset{
	level/.style   = { ultra thick, blue },
	connect/.style = { dashed, red },
	notice/.style  = { draw, rectangle callout, callout relative pointer={#1} }
%	label/.style   = { text width=2cm }	
}
\hspace*{-0.5cm}
\begin{tikzpicture}

	%	 layer 1
%	\node [neuron_type] (var_name) at (X,Y)  {$Text$} ;
	\node [label={\tiny Difficulty   },input_neuron] (ain1) at (4,4)  {$D$} ;
	\node [label={360:\tiny Intelligence},input_neuron] (ain2) at (6,4)  {$I$} ;
	
	%	layer2
%	\node [input_neuron] (in3) at (4,3)  {$C$} ;
	\node [label={360:\tiny Grade},input_neuron] (ain4) at (5,2.5)  {$G$};
	\node [label={360:\tiny SAT},input_neuron] (ain5) at (7,2.5)  {$S$} ;
	
%	%	layer3
%	\node [label={\tiny Letter}] (lab3) at (3,0.75)
	\node [label={180:\tiny Letter},input_neuron] (ain6) at (5,0.75)  {$L$} ;
	
	\draw [->, line width=0.5mm] (ain1) -- (ain4);
	\draw [->, line width=0.5mm] (ain2) -- (ain4);
	\draw [->, line width=0.5mm] (ain2) -- (ain5);
	\draw [->, line width=0.5mm] (ain4) -- (ain6);
	
	
		\node[draw,rectangle callout,callout absolute pointer = (ain1.west)] at (2.5,4) {\tiny
			
			%\begin{table}[]
			\begin{tabular}{|c|c|}
			\hline
			\rule{0pt}{0.25cm}$d^0$ & $d^1$\\
			\hline
			0.6 & 0.4\\
			\hline
			\end{tabular}
			%\end{table}
		};


		\node[draw,rectangle callout,callout absolute pointer = (ain2.north)] at (6,5) {\tiny
			%\begin{table}
			\begin{tabular}{|c|c|}
			\hline
			\rule{0pt}{0.25cm}$i^0$ & $i^1$\\
			\hline
			0.7 & 0.3\\
			\hline
			\end{tabular}
			%\end{table}
		};
		
		\node[draw,rectangle callout,callout absolute pointer = (ain4.west)] at (2.4,2.2) {\tiny
			\begin{tabular}{|c|c|c|c|}
			\hline
			\rule{0pt}{0.25cm}&$g^1$ & $g^2$ & $g^3$\\
			\hline
			$i^0$,$d^0$ & 0.3 & 0.4 & 0.3\\
			\hline
			$i^0$,$d^1$ & 0.05 & 0.25 & 0.7\\
			\hline
			$i^1$,$d^0$ & 0.9 & 0.08 & 0.02\\	
			\hline
			$i^1$,$d^1$ & 0.5 & 0.3 & 0.2\\
			\hline
			\end{tabular}
			
		};


	\node[draw,rectangle callout,callout absolute pointer = (ain5.south)] at (7,1.3) {\tiny
		\begin{tabular}{|c|c|c|}
		\hline
		\rule{0pt}{0.25cm}& $s^0$ & $s^1$\\
		\hline
		$i^0$ & 0.95 & 0.05\\
		\hline
		$i^1$ & 0.2 & 0.8\\
		\hline
		\end{tabular}
	};


	\node[draw,rectangle callout,callout absolute pointer = (ain6.south)] at (5,-0.5) {
		\tiny
		\begin{tabular}{|c|c|c|}
		\hline
		\rule{0pt}{0.25cm}& $l^0$ & $l^1$\\
		\hline
		$g^1$ & 0.1 & 0.9\\
		\hline
		$i^2$ & 0.4 & 0.6\\
		\hline
		$i^3$ & 0.99 & 0.01\\
		\hline
		\end{tabular}
	};

\end{tikzpicture}