AS/A2 Stats 2 Stats 3

S1 Topic 4: Correlation and regression
Using the regression line
Estimate the y on x regression line by moving the red line to try to make the total yellow area as small as possible. Once a value has been chosen for the explanatory variable,x , then a predication can be made, using the graph, of the corresponding response value, y. This is shown in blue

Please enable Java for an interactive construction (with Cinderella).

Such predications should only be made for values within the range of readings of the explanatory variable. This is called interpolation. Predications for values outside the range of readings is called extrapolation and is usually unreliable.