How to create a second order linear model in MATLAB if I have 5 predictors?

Basically, I have a dataset with 5 predictors and one target variable. I need to fit a second order linear model in MATLAB. So do I need to create a total of 20 predictor variables and then use fitlm or is there any other approach so that I donot need to create 20 variables.

Answer 1

[Star Strider]

I am not certain what you are asking.

If by ‘second order linear model’ you are describing a quadratic, this may do what you want:

Predictors = rand(10,5);                                            % Create Data
Target = rand(10,1);                                                % Create Data

DM = [Predictors.^2, Predictors, ones(size(Target))];               % Design Matrix
B = DM \ Target;                                                    % Estimate Parameters
FitTarget = DM * B;                                                 % Predicted Values

You can easily adapt it to work with fitlm and regress.

If this is not what you intend, please describe what you want to do in more detail.