1. Graphical Misrepresentations of Data
Lesson 2 - 4
Graphical Misrepresentations of Data

2. Objectives
Describe what can make a graph misleading or deceptive

3. Vocabulary
None New

4. Common problems: Vertical Axis
Inconsistent vertical scaling
Incorrect vertical scaling
Vertical axis that doesn’t start at zero
Scaling in pictures different than that reflected by the data
Class widths
Values overlap
Class widths different

9. Characteristics of Good Graphics:
Label the graphic clearly and provide explanations if needed
Avoid distortion. Don’t lie about the data
Avoid three-dimensions. Look nice, but often distract reader and result in misinterpretation
Don’t use more than one design in the same graphic.
Let the numbers speak for themselves
Sometimes graphs use a different design in a portion of the graphic to call attention to it

10. Summary and Homework Summary Homework:
Good graphs speak for themselves
Avoid well-intended, but misleading flaws
Homework:
pg : 1, 2, 7, 8, 13, 14