Have an idea?

Visit Sawtooth Software Feedback to share your ideas on how we can improve our products.

Simulator Calculations after using linear coding in CBC/HB

I have a related question.  I understand that when you specify a linear pricing attribute in CBC/HB, regardless of the values you put in there, CBC/HB will zero-center them when calculating the utilities.  My question is, when I create the simulator (in Excel, not using Sawtooth's simulator) and I want to use this linear term to break out each of the original individual price points (to create point estimates for each original price point), do I use the non-zero-centered values that I put into CBC/HB, or do I need to zero-center the values that I had put into CBC/HB and use these zero-centered values?  In other words, even though CBC/HB will zero-center the values when it does its calculations, when it gives you the utilities for the price attribute, are these utilities adjusted to be used with the non-zero-centered values that were put into CBC/HB?
related to an answer for: linear coding
asked Apr 5, 2012 by anonymous

1 Answer

+4 votes
The simulator provided in our SMRT software also zero-centers the values for linear attributes.

If you estimated the parameters that way, you should also do so in simulation.
answered Apr 5, 2012 by Walter Williams Gold Sawtooth Software, Inc. (23,105 points)
Thank you.  So I should always use the zero-centered values in my Excel simulator regardless of whether I zero-centered them when I put them into CBC/HB?
Whenever you use linear coding in CBC/HB, the values will always be zero-centered for estimation.  So that is a step that you do not need to do yourself.

Given that CBC/HB always centers linear terms, your simulator should always do the same.
Thank you for your help!