Question

I don't know how to interpret the residual (-1.3829)What should I say? the equation of the least-squares regression line is ŷ = 0.4684X + 64.69888

Answer 1

A Residual is just the difference between the observed value in an experiment or survey and the value predicted by the regression line.

This means that the Residual can be calculated using the formula:

$\begin{gathered} r=y-\hat{y} \\ \text{where,} \\ y=\text{observed value} \\ \hat{y}=\text{predicted value} \end{gathered}$

Thus, if we are told that a piece of data has a residual of -1.3829, it means that the difference between one of the observations from the experiment or survey conducted and the value predicted by the regression line is -1.3829.

Mathematically,

$-1.3829=y-\hat{y}$