Hi all,

I am currently building a prediction model and aim to improve the model fit. I came across two methods of increasing model fit: **(1) interaction term**and **(2) squared term**.

Can someone pls show me how I can confirm if adding these terms will indeed increase the model fit (i.e. what analytical approach can we use to compare the model fit between two models, one with the additional term and one without)?

Thanks so much!