Displaying the results
In this part of the examination, you will be required to analyse and evaluate the data recorded in the first part of the experiment.
Drawing graphs and charts
There are several methods for displaying the data, but usually you will have to draw a line graph.
Pie charts
Pie charts can be used to show the make-up of something, when comparing to the total data. Each section is a category or name and the size of the pie segment represents a percentage of the whole. An example of this is how the UK electricity supply is met from different renewable and non-renewable sources, as a percentage of the total energy supplied.
Bar graphs
Bar graphs are used when the \(\text{x}\)-axis is a range of categories, names or labels (categoric variables) and the \(\text{y}\)-axis can take any numerical value (continuous variable). An example of this would be the height a golf ball bounces to when dropped on different surfaces. The bounce height is a continuous variable and the different types of surface are categoric variables. Bar graphs can also be drawn to display fixed or discrete numbers (discontinuous variables) on the \(\text{x}\)-axis, eg months in a year or the number of legs possessed by animals and insects (2, 4, 6, 8).
Line graphs
Line graphs are used when both axes are continuous variables because they can take any numerical value. An example of this might be a graph to show the time taken for a paper cake case to fall from different heights.