(Description) Figure 9 (a) The values 235, 255, 270 and 240 represented by shapes. Here the different lengths of the two shapes used can mislead (as can the fact the ‘bars’ do not start at zero). (b) The same values represented by piles of money. Here the fact that there is a 3D representation is misleading: is it height or volume that represents the four values?

Visualisation: Visual representations of data and information

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This figure shows 2 charts designed with images of real items representing the columns.

Chart (a) is similar to a horizontal bar chart. Each bar consists of a train locomotive and some carriages. Each bar has a label showing its length (although there are no scales). From the top the lengths are:

A 235
B 255
C 270
D 240

Chart (b) simply shows some piles of money (notes). Although differences in height of the money piles can be noted it is only possible to make very rough judgements about their relative heights. The piles are labelled from left to right:

A 235
B 255
C 270
D 240

3.2 Cheating with bar charts