Plotting Uncertainty for a Sample of Functions

Question

I am trying to produce a plot showing the variation in a sample of functions. It should look like this plot or that plot. I tried to use SmoothDensityHistogram. Even for the following simple example this does not look right. Do you have other suggestions?

My approach so far was:

dx = 0.01;
functionSample = 
Table[noise = Random[NormalDistribution[0, 0.5]]; 
Table[ {x, x (1 - x) + noise}, {x, 0, 1, dx}], {i, 1, 60}];
var = Flatten[diff, 1];
ListPlot[functionSample[[All, All]], Joined -> True]
SmoothDensityHistogram[var, 
ColorFunction -> (Blend[{White, Black}, #] &)]

Producing

Maybe things can be improved by choosing a small bandwidth of the kernel in x direction and a larger in y direction of the underlying kernel smoother.

Answer 1

Just for visualisation purposes you can use Filling:

dx = 0.01;
n = 10;
functionSample = Table[noise = Random[NormalDistribution[0, 0.5]];
                       Table[{x, x (1 - x) + noise}, {x, 0, 1, dx}]
                      , {i, 1, n}];


ListPlot[Evaluate[{Mean[{##}], ##} & @@ functionSample], 
         Joined -> True, Filling -> (# -> {1} & /@ Range[2, n + 1]), 
         PlotStyle -> {Directive[[email protected], Orange], Sequence @@ Array[Thin &, n]}, 
         FillingStyle -> Directive[[email protected], Gray]]

PlotStyle -> {Directive[[email protected], Orange], Sequence @@ Array[None &, n]}, 
FillingStyle -> Directive[[email protected], Gray]