\documentclass{standalone}
\usepackage{pgfplots}
\usepackage{pgfplotstable}
\usepackage{tikz}
\usetikzlibrary{arrows,automata,mindmap,shapes,positioning,snakes,calc}
\tikzset{
tag/.style={
rectangle,
draw=black, very thick,
text width=4em,
minimum height=2em,
text centered},
commit/.style={
circle,
draw=black, very thick,
text width=1em,
minimum height=1em,
text centered},
point/.style={coordinate},
}
\pgfplotsset{compat=1.6}
\begin{document}
\begin{tikzpicture}
\pgfplotstableread{
plot1 plot2 plot3 plot4
0 0 0 0
3.466 2.058 0 0
4.262 2.976 0.001 0
3.822 3.168 0.006 0.008
2.953 2.936 0.019 0.063
2.065 2.492 0.046 0.265
1.332 1.977 0.092 0.734
0.797 1.478 0.164 1.508
0.443 1.045 0.268 2.44
0.228 0.698 0.412 3.219
0.107 0.438 0.598 3.524
0.046 0.256 0.831 3.219
0.017 0.138 1.109 2.44
0.006 0.067 1.429 1.508
0.002 0.029 1.78 0.734
0 0.01 2.141 0.265
0 0.003 2.479 0.063
0 0.001 2.736 0.008
0 0 2.808 0
0 0 2.465 0
0 0 0 0
}\dummydata
\begin{axis}[
samples=30,
domain=-4:4,
samples y=0, ytick={1,...,4},
zmin=0,
area plot/.style={
fill opacity=0.75,
draw=orange!80!black,thick,
fill=orange,
mark=none,
}
]
\pgfplotsinvokeforeach{4,3,...,1}{
\addplot3 [area plot] table [x expr=\coordindex, y expr=#1, z=plot#1]
{\dummydata};
}
\end{axis}
\end{tikzpicture}
\begin{tikzpicture}[
declare function={
normal(\m,\s)=1/(2*\s*sqrt(pi))*exp(-(x-\m)^2/(2*\s^2));
}
]
\begin{axis}[
samples=30,
domain=-4:4,
samples y=0, ytick=data,
zmin=0,
area plot/.style={
fill opacity=0.75,
draw=none,
fill=blue!70,
mark=none,
smooth
}
]
\addplot3 [black, thick] table {
0 4 0
-0.75 3 0
-1.9 2 0
-1.2 1 0
};
\addplot3 [area plot] (x,4,{normal(0,1)});
\addplot3 [area plot] (x,3,{normal(-0.75,1)}) -- (axis cs:-4,3,0);
\addplot3 [area plot] (x,2,{normal(-1.9,0.7)}) -- (axis cs:-4,2,0);
\addplot3 [area plot] (x,1,{normal(-1.2,1.2)}) -- (axis cs:-4,1,0);
\end{axis}
\end{tikzpicture}
\end{document}