There has been a lot of discussion about pie charts and bar charts lately. I and many other know-it-alls have clearly stated that pie charts are the red-headed stepchildren in the family of chart types. In Peltier Loves Pie I provided some guidelines to follow if you still insist on using pie charts.
In this post I am giving bar charts equal time.
Bar charts are widely used, and in most cases they present an improvement over pie charts. According to William Cleveland, the effectiveness of different human visualization skills are ranked as follows:
- Position along a common scale
- Position along identical unaligned scales
- Angle or slope
A bar chart relies on the lengths of its bars to convey information. Length is found higher than a pie chart’s angles or areas in Cleveland’s hierarchy of human perception, so bar charts are better than pie charts for presenting data. A bar chart also uses the same color for each point, so there should not be any unintended weighting of values by color. [Read more…] about Peltier Goes Bar Hopping