Differences between stepwisefit and robustfit?

I am trying to do a linear regression between y (100x1) against X (100x5 variable 1,2,3,4,and 5).

What is the best linear regression method I should use: Robustfit or Stepwisefit?

Many thanks.

[Rohit Reddy Madasani]

Hi Leon,

Your choice of model depends on precisely what you are trying to explain. You should have some a priori knowledge that explains

1.Why you are creating a model.

2.What you think that the relationship between the variables should be modeled as.

3.Why you think that the relationship between the variables should be modeled.