Title: Example 1: Discussion
Course: UGQuants (SSPS) > Section: Data Visualisation

example 1

Most likely, you have noticed that the graph was hard to interpret: if we want to compare the relative distribution in categories - e.g. the share of people in good health amongst those with no internet access against those who surf on the internet every day -, absolute counts are not helpful. Since overall, we can see that there are much more people using the internet daily than in any of the other user categories, a direct comparison of absolute counts is impossible.

Additionally, the graph looks untidy. Not all counts are presented and it overall is not very appealing to the eye, although graphs can be a good method of maintaining your reader's interest.

In this graph, we have elected to express each internet user category as separate sample, so that all the health status numbers add up to 100%. This resembles column percentages if we had produced a crosstable of the two variables. It makes the percentages directly comparable. We can now see that of those people with no internet access, 18% are in very good health as opposed to 36% amongst the daily internet users.

There is an appealing colour scheme, no clunky outlines, and the grid lines are unobtrusive to let the viewer focus on the most important information in the graph. Percentages have only been presented for the more common health categories to not overload the graph, but there is enough information to work out the summary share of people in bad and very bad health.