Uploaded September 2012 | Updated September 2026, 3 weeks ago

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Have you ever wondered in fitting a line to data on a scatter plot that you work to minimise the vertical distances of points from the line - not the actual distances (perpendicular to the line)? Or why you square numbers rather than work with the natural thing which would be absolute value?

In this video I explain why we calculate the line of best fit the way we do, and explain the mathematics behind the formula for the best line. It really isn't that bad!