The difference between an observed y value and the value predicted by the line is called the:

1. Each point sits some vertical distance from the fitted line. 2. That gap is what the fitting procedure works to make small. 3. The term y0 minus y-hat is called the error or residual. 4. Slope and intercept describe the line itself rather than a point's distance from it. _Source: OpenStax Introductory Statistics 2e (CC BY 4.0), Ch 12 'Linear Regression and Correlation', sections 12.1-12.6_