%%%------------------------------------------------------------------------------------------------------------
 \begin{tikzpicture}
\begin{scope}
\node [anchor=center,circle,draw,ublue,very thick,minimum size=3.5em,fill=white,drop shadow={shadow xshift=0.1em,shadow yshift=-0.1em}] (neuron) at (0,0) {};
\node [anchor=east] (x1) at ([xshift=-6em]neuron.west) {$x_2$:票价够低？};
\node [anchor=center] (x0) at ([yshift=3em]x1.center) {$x_1$:距离够近？};
\node [anchor=center] (x2) at ([yshift=-3em]x1.center) {$x_3$:女友喜欢？};
\node [anchor=west] (y) at ([xshift=2em]neuron.east) {$y$:去？还是不去？};

{
\draw [->,thick] (x0.east) -- (neuron.150) node [pos=0.5,above,yshift=0.2em] {\small{$w_1=1$}};
\draw [->,thick] (x1.east) -- (neuron.180) node [pos=0.5,above,yshift=-0.1em] {\small{$w_2=1$}};
\draw [->,thick] (x2.east) -- (neuron.210) node [pos=0.5,above,yshift=0.1em] {\small{$w_3=1$}};
}
\draw [->,thick] (neuron.east) -- (y.west);

\node [anchor=center] (neuronmath) at (neuron.center) {\small{$\sum \ge \sigma$}};

\end{scope}
\end{tikzpicture}
%%%------------------------------------------------------------------------------------------------------------


