Clustering bars in 2-dimensional bar chart

Rather than using a 3-dimensional bar chart, it is usually easier to assess the relationships between two variables from 2-dimensional bar charts. The bars can be clustered by either variable and it is often informative to examine both of these displays.

Rank and age

The diagram below again shows the rank and ages of academic staff in a university in the USA.

The bars are initially clustered by rank, allowing us to compare the age distributions of the different ranks.

Select the option Age from the pop-up menu to cluster the bars by age, allowing us to compare better the distributions of rank at the different ages.