- A frequency distribution or histogram is useful in identifying the shape of a distribution.
- A histogram is constructed as follows.
- Divide the range of the data into intervals (intervals are usually of equal width).
- Label the horizontal axis to conform to the intervals selected.
- Determine the frequency of occurrences within each interval.
- Label the vertical axis so that the total occurrences can be plotted for each interval.
- Plot the frequencies on the vertical axis.

- The issue of intervals being too ragged, too coarse ... See Figure 10.1 on page 360.
- Example 10.2 on page 359, Example 10.3 on page 360

Meng Xiannong 2002-10-18