I am getting familiar with SPSS, specifically the Automatic Linear Modeling functionality. I first ran SPSS, using Best Subset method which gives me the result of "best" variables. Being uncertain, I run again in Excel with the same data. Much to my surprise, the coefficients of one variable are not the same: they are the opposite of each other, having identical attributes. I am ok with the different intercepts but opposite coefficients imply very different stories about the data.
What is the meaning of this? What did I do wrong? What model should be used? Does this mean I have to check again everytime SPSS return a model from best subset functionality?
This is the transformation summary.
Role (Summer_transformed) Predictor
Actions Taken (Summer_transformed) Change measurement level from continuous to ordinal
Role (Month_transformed) Predictor
Actions Taken (CK_transformed) Trim outliers
Actions Taken (Month_transformed) Trim outliers
Role (CK_transformed) Predictor