what is non linear regression model
DEFINITION of 'Nonlinear Regression'. A form of regression analysis in which data is fit to a model expressed as a mathematical function.Simple linear regression relates two variables (X and Y) with a straight line (y = mx + b), while nonlinear regression must generate a line (typically a curve) as if every value of Y was a random variable.The goal of the model is to make the sum of the squares as small as possible.onlinear regression modeling is similar to linear regression modeling in that both seek to graphically track a particular response from a set of variables.