Simple regression models describe the relationship between a single predictor variable
and a response variable.
||Fit a straight line.
||Fit a polynomial curve. Polynomials are useful when the function is smooth, a polynomial of a high enough degree estimates any smooth function. Polynomials are used as approximations and rarely represent a physical model.
||Fit a logarithmic function curve.
||Fit an exponential function curve.
||Fit a power function curve.