Plot rate of change in $x$ axis of list of points

Question

I have a list of points, that may have clusters in some of the $x$ axis values, and my goal is to get a function that shows that graphically.

Something like this, but the red function is "hand drawn", it's just for reference.

The high points of the red plot shows where the clusters are and the low points where are the points that are most isolated.

Answer 1

values = Transpose[{Join[
     RandomVariate[NormalDistribution[1.5, 0.3], 100], 
     RandomVariate[NormalDistribution[3.5, 0.3], 100]], 
    RandomVariate[NormalDistribution[1.5, 0.1], 200]}];
Overlay[{ListPlot[values, PlotRange -> {{0, 5}, {0, 2}}, 
   ImagePadding -> 25], 
  SmoothHistogram[values[[All, 1]], Axes -> False, 
   PlotRange -> {{0, 5}, {0, All}}, ImagePadding -> 25]}]