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Does estimation in Lighthouse handle 0's in an imported design correctly even if the I didn't activate the ASD settings?

I generated a design within Lighthouse without specifying prohibitions or ASD relationships between attributes via prohibitions  in  the menu, I had just set it to Design Type ASD.
Then I exported the design and manipulated it to impose minor prohibitions and alternative-specific relationships.
For context: Each task was to feature a free option of a product and two paid options (multiple varied prices per feature dependent on the presence of said features).

Then I re-imported the design with added Zeros and there was no warning  (such as "don't expect/accept Zeros because you didn't specify any ASD relationships with prohibitions").

When I imported simulated choice data the estimation also proceeded without any warnings.

Can I assume that Lighthouse will treat the design Zeros just like MBC or CBC/HB?
Will it just utilize the available information when level (>0) occurred and as long as my design correctly reflects a de facto alternative-specific setup it will estimate accordingly also without me specifying primary and conditional attribute via prohibitions in the attribute tab?

Without a primary attribute I expected that any inherent benefit of a free option will be reflected in the estimates of the prices. But with the simulated data the actual estimates do not give any indication whether that is the case. Now I'm not sure and wondering if I actually need to include a primary attribute in the design since I don't have an ASconstant term (as in the MBC context) to capture the utility of "free" separately from the price attributes.  

Can anybody advise? Thanks!

PS: I realized I prob should have logged in with my company account but I assure that I'm the holder of a valid license ;)
asked Sep 28, 2017 by alex.wendland Bronze (2,080 points)
edited Sep 28, 2017 by alex.wendland

1 Answer

+1 vote
Best answer
Zeros in the design file will be sent into utility estimation as a vector of zeros in the X matrix.  (For example, for a 5-level attribute, under K-1 part-worth coding, it would code a 0 as a vector of 4 0s in the design file.)

But, you really need to have a "primary" attribute to capture the alternative-specific constants (the ASC).  Price alone cannot properly model and capture the utility of an alternative.
answered Sep 28, 2017 by Bryan Orme Platinum Sawtooth Software, Inc. (152,955 points)
selected Nov 13, 2017 by alex.wendland