i trying to draw an automata using tikz package, and i want to decrease the size of node and labels on each edge , im have trying to put the option [scale=0.5] but it doesn't work ! I have :
\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{arrows,positioning,automata,shadows,fit,shapes}
\begin{document}
\begin{tikzpicture}[shorten >=1pt, node distance=2.5cm, on grid, auto,thick,initial text=,scale=0.3]
\node[state, initial] (0) {0};
\node[state] (1) [above right =of 0] {1};
\node[state] (2) [right =of 0] {2};
\node[state,accepting] (3) [right =of 2] {3};
\path[->] (0) edge node {a:a / 1.61} (1)
(0) edge node {b:b/ 0.22} (2)
(2) edge [loop below] node {b:a/ 0.69} ()
(2) edge node {b:a/ 0.69} (3);
\end{tikzpicture}
\end{document}
this give me a not pretty picture :

