So far we have covered a range of different chart types for representing data. In this final topic, we consider various other charts, including pictograms, sector graphs (pie charts), line graphs, and divided bar charts.
Which type of chart to use?
The type of chart we choose will depend primarily on the type and size of the data.
- Type: some charts are more suitable for numerical data, while others are better at representing categorical data.
| Numerical | Categorical |
|---|---|
| dot plot | pictogram |
| stem-and-leaf plot | divided bar chart |
| line graph | sector graph (pie chart) |
| frequency polygon | bar chart |
| histogram | Pareto chart |
| box plot |
- Size: some display types (like sector graphs, pictograms, divided bar charts and dot plots) are not suitable for large data sets.
Practice questions
Question 1
The grouped bar chart shows customer satisfaction ratings for different cars, broken down by gender. The red rows represent males; the blue rows, females.
Which of the following statements are true?
Honda received the highest ratings.
True
AFalse
BFord received the lowest ratings among Males.
True
AFalse
BBoth genders agree on the rank order in which the cars are rated.
True
AFalse
BAs a group, the women seem to be tougher raters; they gave lower ratings to each car than the men gave.
True
AFalse
BFemales prefered the cars that were red.
True
AFalse
B
Question 2
The graph represents the number of iTunes sales (in millions) and iPod sales (in hundreds of thousands) every 3 months between 2003 and 2007.
How many iTunes sales were there in the first quarter of 2006 (2006 Q1)?
How many iPod sales were there in the first quarter of 2006?
How many more iTunes sales were there than iPod sales in the first quarter of 2007?
How many iTunes sales were there in 2006?