Neural Net JMP 14 SAS Script - Converting to excel formula

[#1]

Hi All,

I am relatively new to JMP and have created a Neural Network model that fits pretty well. I am trying to implement the output (model) in excel. I exported the SAS script and currently I am trying to convert the formula in the script to excel. The following formula in the script is tripping me. 

H1 = tanh(.5*(-1.31215248048067*((ENGINE_MODEL="XXX")-(ENGINE_MODEL="YYY"))   + -0.0627257389428689*......

Engine_Model is a binary input to the model (can be XXX (0) or YYY(1)). 

I need soem help in interpreting the term (ENGINE_MODEL="XXX")-(ENGINE_MODEL="YYY"). Does it simply mean that it is difference between the value of ENGINE_MODEL="XXX" and ENGINE_MODEL="YYY"? In that case it is just a constant number. Also the calculated value of H1 in excel and JMP do not match with that assumption.

Any help is appreciated.

[#2]

Hi,

I think this is about how JMP codes categorical factors in regression models (Neural Nets, although exotic, are just complex regression models).

This from JMP's statistics knowledge portal should help.

"To integrate a two-level categorical variable into a regression model, we create one indicator or dummy variable with two values..."

I would suggest you experiment with a very simple Neural Net. For example, a neural with only Engine Model and 1 node. Then check that the JMP prediction and your conversion of this simple model are in agreement.