Transform Variables

 

MultiRate can perform transformations on the analysis data. The transformed data is then saved in a new column in the SQL table, so that the original data is not overwritten. This tool always transforms the selected column within the Training Table. It also transforms the column in the Test Table if the test data and training data are not located in the same table.

 

When new data is brought in, after Selecting Data Types, MultiRate will suggest truncation if the Credibility Standard < Total Exposure / 20. Variables can also be transformed by selecting Tools -> Transform Input Variables from the Menu bar.

 

There are two types of transformations available:

 

Transformation

Formula

Description

Truncate

Every value below the specified limit is unchanged and every value over the limit is set to the limit.

Generalized Log

Takes the log of one plus every value. Parameters "a" and "b" default to zero, but can be changed to achieve the desired transformation. Increasing "a" will shift the transformation, so as "a" increases, the x value that results in a transformed value of 0 will decrease. This can be useful when there are negative values in the data. Increasing "b" will dampen the effect of the transformation, so as "b" increases, the transformed variable will approach the original variable.

 

 

The Input Data Transformation window looks like this: