Transform node - what does _SCALEVAR_ mean?

[TomaszZ_]

Hi!

In Enterprise Miner I am using Transform Variables node.

After performing automatic transformation results window shows formula which has been applied (ex. below).

Input Name                          Role      Level      Name                                 Level            Formula

description_length                  INPUT    INTERVAL    SQRT_description_length             INTERVAL    Sqrt(_SCALEVAR_)

document_length                     INPUT    INTERVAL    SQRT_document_length                INTERVAL    Sqrt(_SCALEVAR_)

keydown_repeatable                  INPUT    INTERVAL    LOG_keydown                         INTERVAL    log(_SCALEVAR_  + 1)

Does anyone know what _SCALEVAR_ means in this context? It looks like variable have been standarised - but these is only my guess.

Thanks in advance for your help.

T.

[Saxivore]

Took me ages to work this one out ...  It's the transformation of the Scaled variable.  Which is (x-min)/(max-min).  Turns it into values from 0 to 1.

[Amruta]

Saxivore said it correctly. The transform node scales the variable in the range 0 to 1. To look at the exact formula you can add a SCORE node after the tranformation node and in the output window go to the SAS CODE window. This is the place where you can see the exact numbers used to scale your variables.

Hope that helps

Regards,

Amruta