Misleading graphs
Charts are often used in the media to show comparisons and describe trends. At times, they are also used to misrepresent information and promote a biased view.
Some of the ways in which a chart can be misleading include:
- Biased labelling
- Missing a scale on one of the axes
- Not starting the vertical axis scale at zero
- Using a scale that isn't uniform
- Having an inappropriate scale for the given data (making variations seem less important than they are)
- Only displaying a select portion of the data
- Using the wrong type of chart
- Using inappropriate scaling on chart elements like bars or sectors.
- Using unconventional methods
Practice question
Question 1
The Australian Labour Party released this graph after Tony Abbot was elected as Prime Minister.
A vertical bar graph titled "Women in Cabinet around the World". The vertical axis consists of numbers from $0$0 to $12$12, marked and labeled uniformly in increments of $2$2. There are $15$15 countries listed on the horizontal axis. Each country is represented by a blue vertical bar, labeled by a number just above the horizontal axis. The countries are arranged from the one with the highest bar on the left to the lowest bar on the right. Canada is on the leftmost with $12$12. Rwanda has $11$11. Cuba and Uganda each have $8$8. Indonesia has $7$7. New Zealand has $6$6. Liberia and Zimbabwe each have $5$5. Afghanistan, Egypt, India, and the United States each have $3$3. China and Malaysia each have $2$2. Australia is last, with $1$1. The bar for Australia is marked with a downward arrow labeled “Tony Abbott’s new cabinet.”
Which of the following comments apply:
This graph is misleading because the scale on the vertical axis is not uniform.
AThis graph is misleading because it claims that there are always an equal number of male and female cabinet members to choose from
BThis graph is misleading because it claims that all cabinet sizes are the same.
CThis graph is misleading because there are no European countries included.
D