The vertical distance between any data point and a line approximating the data points is called an error.

Question

Quizplus · Accepted Answer

The vertical distance between any data point and a line approximating the data points (such as a line of best fit in linear regression) is indeed called an error, specifically a residual error, which measures the discrepancy between the observed value and the value predicted by the model.

The Vertical Distance Between Any Data Point and a Line