6. Summary of week 5

This week you have looked at three graphical representations suitable for presenting continuous data: line graphs, box plots and histograms. These were presented in order of difficulty level from a school curriculum point of view. All pupils in the UK will be expected to plot and interpret line graphs by age 14, some will have looked at box plots by this age and only a few may have come across histograms, particularly with unequal class widths.

When presenting graphical representations to learners at any level, the key point of which you need to be aware is the type of data . From a teaching perspective, you should ensure you use appropriate graphs for the data you are using in the classroom: line graphs for showing patterns over time, box plots for visualising the shape of numerical data sets (either discrete or continuous), bar graphs for representing frequencies of discrete/categorical data, and histograms or frequency polygons for frequency densities of grouped numerical data.

It is also important to consider what you are trying to show with your graphical representation of the data. For example, a box plot gives a summary, while a bar graph/histogram shows all the detail. A change to axis scales or class intervals can lead to a different visual interpretation of the data. There will be more on misleading graphs in Week 7.