node regression nominal variable automatically transform in interval modalities ?

[yanlu]

Hi everyone , 

I was wondering if the creation of dummy variable for the node regression was an automatical process.

I know it create k-1 modalities interval modalities for a nominal variable which has k modalities 

It's an automatic process ?

Thank for this confirmation

[WendyCzika · Accepted solution]

Yes, the procedures used for regression in EM all internally/automatically create dummy variables for class inputs.  

[rnibbe0]

Thank you Wendy for this clarification.

Is there a reference point in a SAS manual so I can see how it is doing this 'internally/automatically' to ensure it is doing what I expect?

Thank you!! Rod.