Article / Updated 03-26-2016
In econometrics, the standard estimation procedure for the classical linear regression model, ordinary least squares (OLS), can accommodate complex relationships. Therefore, you have a considerable amount of flexibility in developing the theoretical model. You can estimate linear and nonlinear functions including but not limited to
Polynomial functions (for example, quadratic and cubic functions)
Inverse functions
Log functions (log-log, log-linear, and linear-log)
In many cases, the dependent variable in a regression model can be influenced by both quantitative variables and qualitative factors.