Tree Map
Tree map is a hierarchical map made up of nested rectangles frequently used in business Intelligence which helps organizations to understand the data hierarchically. The tree map was invented in the early 1990s by Ben Shneiderman at University of Maryland College Park.
To construct a tree map we need the following:
- The Data should be hierarchical with several levels.
- The size of Rectangle and color are used for describing or differentiating the characteristics of the data.
The above is the Treemap figure the top 15 countries which would be producing the total percentage of mismanaged plastic waste in the year 2025.The majority of the countries that would fail to manage the plastic waste are from the Middle East Countries. The China will be the top country which would produce nearly 25% of mismanaged plastic waste in the year 2025.We could see the size of the China’s rectangle compared with the brazil’s rectangle in the below diagram.
The size directly signifies the proportion of the plastic waste produced by the country. The color signifies the various qualitative variables i.e., the countries in the treemap.
Let’s consider the treemap which shows the Top 10 Happiest countries in the world.
We could even see the ordering of the countries using the tree map. In this we could see both the 1st(FINLAND) as well as 10th(United Kingdom) rectangle’s size seems to be same. Why this Happens?
The reason behind this is we have used the Life Evaluation Index to measure the Happiness. The value ranges from 0 to 10 and most of the top 10 countries are around 7 and hence we could not see a drastic difference in size of rectangle between Finland and United Kingdom.
Another Interesting pattern we could observe from the tree map is that 9 of the top 10 countries are European Countries and the remaining one New Zealand is from Australian continent.
Limitations of Tree Map:
- You cannot display data that varies in magnitude.
- The variable for the size of the rectangle cannot have a negative value.
- The rectangles are automatically ordered by area within the parent node; the chart does not provide for any more sorting options.
- Treemap having a large number of data points on a single level are unsuitable for print.
THE CODE FOR ABOVE VISUALISATION
“The purpose of visualization is insight,
not pictures” — Ben Shneiderman
Hence try to observe a picture and get more insights of it.
