Sure, there are other factors at play like how good the student is at that particular class, but we’re going to ignore confounding factors like this for now and work through a simple example ... sums ...

Nonlinear regression uses logarithmic functions, trigonometric functions, exponential functions ... depending on the form of the linear regression equation. Likewise, it’s possible to use ...

For example, in the right hand graph of Figure 2 is a population of Paramecium growing in a laboratory culture. The pattern of growth is very close to the pattern of the exponential equation.