Example of Treemaps
Treemaps can be useful in cases where histograms or bar charts are ineffective. This example uses the Cities.jmp sample data table, which contains meteorological and demographic statistics for 52 cities. Compare the bar chart to the treemap.
Create a bar chart representing ozone levels in each of the 52 cities:
1. Select Help > Sample Data Library and open Cities.jmp.
2. Select Graph > Chart.
The launch window appears.
3. Select OZONE and click Statistics.
4. Select Mean.
5. Select city and click Categories, X, Levels.
6. Click OK.
The report window appears.
Figure 10.2 Ozone Levels in a Bar Chart
Although it is easy to see ...