M7-Quantitative Decision Methods-S6 - Regression

A linear regression line in a scatter dataset can be calculated as follows:

$y=ax+b$ $b={\frac {n\sum xy-\sum x\sum y}{n\sum x^{2}-(\sum x)^{2}}}$

This is based on regression of the vertical distances of the points in the dataset. If you would draw the line based on the horizontal distances it would be:

$b={\frac {n\sum xy-\sum x\sum y}{n\sum y^{2}-(\sum y)^{2}}}$