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Chapter 1: Introduction and Graphical Displays
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Definition: Bar Chart or Bar Graph
A bar chart or bar graph is a graph that uses vertical or horizontal bars to
represent the frequencies of different categories in a qualitative data set.
Notes:
A bar chart or a bar graph is a valuable presentation tool, since it is
effective at reinforcing differences in magnitude for the different
categories.
Bar charts permit the visual comparison of data by displaying the
magnitude of each category as a horizontal or vertical bar.
Bar charts are useful when the data set has categories (e.g. hair color,
gender, etc.) and data values that are qualitative in nature.
Observe that the bars in the chart are separated equally from each
other.
Example 1-6:
The following data was taken from the 2005 American
Housing Survey for the United States. The table gives the number of Units
in a Structure and the total number of rented units. All data values are in
thousands. Display the information using a bar chart.
Source
:
http://www.census.gov/hhes/www/housing/ahs/ahs05/tab1a1.html