Fitted values
To assess how well a particular linear model fits any one of our data points, (xi, yi), we might consider how well the model would predict the y-value of the point,
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= b0 + b1 xi |
These predictions are called fitted values.
Residuals
The difference between the i'th fitted values and its actual y-value is called its residual.
ei = yi − | ![]() |
The residuals describe the 'errors' that would have resulted from using the model to predict y from the x-values of our data points.
Note that the residuals are the vertical distances of the crosses to the line.