Scatter Graphs

Scatter graphs are used to compare to sets of data. Pupils will then be able to make comments on the correlation (relationship) between the two. Both these examples show that as one variable increases the other decreases. Age of car Cost Age of car Cost

This shows us that there is no relationship between the two variables. Students must remember that this graph is still telling them something and must be discouraged from interpreting this as ‘useless’ or ‘doesn’t tell me anything’.

Both these examples show as one variable increases the other also increases. Students can use lines of best fit to make further predictions. When drawing these students must make sure that there is approximately the same number of points on both side of the line. Age of antique Cost