1. Investigating associations between two numerical variables
12 Further mathematics
Investigating associations between two numerical variables

2. Investigating associations between two numerical variables
The first step in investigating the association between two numerical variables is to construct a scatterplot. We will illustrate the process by constructing a scatterplot to display average hours worked (the RV) against university participation rate (the EV) in nine countries. The data are shown below.

3. Investigating associations between two numerical variables
Which axis?
When constructing a scatterplot it is conventional to use the vertical or y-axis for the response variable (RV) and the horizontal or x-axis for the explanatory variable (EV).

4. Investigating associations between two numerical variables

5. WORK TO BE COMPLETED
Exercise 3D Questions 1, 4, 5