What it shows
A histogram that is symmetric but has no single peak. Every bin holds the same count, because each value between 0 and 1 is equally likely, as with a fair random number generator.
Because the bars are expected counts rather than a sample, they are exactly level, and the dashed line of the density runs along their tops. Sampled data would vary around that line.
How to read it
There are ten bins, each 0.1 wide, covering 0 to 1.
Every bar is 100 high: 1,000 observations divided equally among ten bins.
Symmetric does not imply bell-shaped; this histogram is symmetric because its left half mirrors its right.
The numbers behind it
- Continuous uniform distribution on 0 to 1. n = 1,000, ten bins of width 0.1.
- Every bin holds 100 (1,000 × 0.1 × 1 = 100).
Ways to use it in teaching
As a short exercise, students simulate a hundred uniform draws and compare their uneven histogram with this one.
Useful against the habit of calling every symmetric shape normal.
Pair it with the symmetric unimodal histogram: both are symmetric, and only one has a peak.
For the summary statistics behind this kind of chart, see our plain-language guide to descriptive statistics.
Sources
Standard formulas for the normal, gamma and uniform distributions.
