Histograms

• A frequency distribution or histogram is useful in identifying the shape of a distribution.
• A histogram is constructed as follows.
  1. Divide the range of the data into intervals (intervals are usually of equal width).
  2. Label the horizontal axis to conform to the intervals selected.
  3. Determine the frequency of occurrences within each interval.
  4. Label the vertical axis so that the total occurrences can be plotted for each interval.
  5. 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