Activity focus
- chart choice
- chart interpretation
- bar chart vs pie chart
Practice set
- Match the graph type to the purpose:
- compare many categories
- show percentage share of a whole
- Explain why a histogram is not appropriate for favourite colour.
- A pie chart shows department-wise percentages that add to
130%.- what is wrong?
Answer key
-
- compare many categories -> bar chart
- share of a whole -> pie chart
- Favourite colour is categorical, not grouped continuous data.
- Pie chart parts must represent one whole, so percentages should total
100%.
Common mistakes
- reading frequency from a chart that is actually in percentages
- assuming pie chart is always better because it looks attractive