Simple linear ... in a 1% decrease in sales—the exact opposite. Now that we know how the relative relationship between the two variables is calculated, we can develop a regression equation ...

“The statistician knows...that in nature there never was a normal distribution, there never was a straight line, yet with normal and linear assumptions, known to be false, he can often derive ...

depending on the form of the linear regression equation. Likewise, it’s possible to use algebra to transform a nonlinear equation so that it mimics a linear equation—such a nonlinear equation ...