Scatter Graphs - GCSE Maths Definition

A scatter graph, also known as a scatter plot, is a statistical graph used to show and analyse data points that are collected in pairs. For example, data on the length and width of leaves on a species of plant; if we suspect there could be a relationship (correlation) between the length and the width, we would record those two pieces of information as a pair; then on a scatter graph, we would plot that pair of values as a point (coordinates).

By taking numerous pairs of readings, and recording them on a scatter graph, we may notice a pattern of how the points are arranged. In some situations, the points on the scatter graph may appear to be roughly in line. An upward line would be a positive correlation, a downward line would be a negative correlation. In the case when no line is evident, we would say there is no correlation. When correlation is present, we can use a scatter graph to make predictions.