It is important to be able to describe the general shape of distributions in order to make quick comparisons.
There are three different basic shapes of distribution. The shape can be seen if you draw a histogram or bar chart of the data and look at the general shape that the area covered by bars covers. The three shapes are:
- Unimodal
- Has a single high point, with the distribution falling away at both sides.
- Uniform
- A flat distribution, no point is significantly higher than another.
- Bimodal
- Has two high points, similar to camel humps.
Figure 1: A unimodal distribution has roughly this shape.
Figure 2: A uniform distribution has roughly this shape.
Figure 3: A bimodal distribution has roughly this shape.
