The document discusses various ways that data can be misleadingly presented in charts and graphs. It provides examples of pie charts that are difficult to interpret because the slices are too small, as well as bar graphs that deceive by manipulating the scale of the y-axis to exaggerate differences. The document advocates for using complete data sets and properly scaling graphs to accurately represent information without bias.

1. Visualcy

2. Satire (from Saturday Night Live)

3. BOO! Misleading: Data have been carefully
selected and presented to portray a desired
(though misleading) result

4. Better: The more complete data-set

5. Better: The more complete data-set

8. NOT ALL ‘DUCKS’ ARE BAD!!
8

9. • Scale increases from equator to poles

10. • Scale increases from equator to poles

11. • Scale increases from equator to poles

12. Sometimes the globe of Google Earth is better than Google
Maps (usually for larger scale mapping)

13. Pie Charts should only be considered if it is being
divided into large slices, usually into major
fractions: ½, ¼, 1/3.

14. Satire, but true! 210 political parties in Iraqi election!

15. BOO! How to Lie with Pie!
Area is now proportional
Not proportional (plotting by radius,
perhaps?)

16. Which is the largest slice?
If you would be unable to slice a REAL pie into the sections you need,
then you should consider a bar-graph or a table instead.

17. Better: same data
Lots of empty space here! What if we delete it?

18. BOO! Same data, but y-axis is half as high:
1) needs y-scale, 2) makes differences seem more
significant than they really are

23. Boo!

24. Poorly-scaled y-axis “flattens”
the differences