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same code same data different "Number of modelled outcome"s

Ask questions about the results reported after estimation. If the output includes errors, please include your model code if possible.
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manes
Posts: 16
Joined: 15 Jun 2023, 13:13
Location: Israel
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same code same data different "Number of modelled outcome"s

Post by manes »

Hi all,
I have estimated an MMNL model with one latent variable using Apollo 0.2.9 on R 4.3.1
I have 723 respondents answering 4 menus each with four alternatives (so the Number of modelled outcomes should be 11568)
When I ran the model again using Apollo 0.3.1 on R 4.3.2, for some reason, the Number of modelled outcomes: 5061, the Model diagnosis was : Relative function convergence and obviously, the estimated parameters were different
The code files are exactly the same, the only difference is that in the old versioned file, I did not specify the "rows=(task==1)" for the LV estimation.
I could not attach the output files as this format is not accepted.
Any idea what could have led to these different estimation results (same code, same data) ?
Anat
Anat Tchetchik
manes
Posts: 16
Joined: 15 Jun 2023, 13:13
Location: Israel
Contact:

Re: same code same data different "Number of modelled outcome"s

Post by manes »

I think that understand the problem, the correct number of models is indeed 5061 = 723*7, I should have specified the "rows=(task==1)" for the LV estimation. I just don't understand how it converged in the previous version (0.2.9).
Anat Tchetchik
stephanehess
Site Admin
Posts: 1002
Joined: 24 Apr 2020, 16:29

Re: same code same data different "Number of modelled outcome"s

Post by stephanehess »

Anat

modelled outcomes is the number of separate dependent variable observations. Relative function convergence is the BGW terminology for convergence.

Using rows=(task==1) is correct, and will indeed give you different estimates as you don't overstate the weight for the measurement model part

Stephane
--------------------------------
Stephane Hess
www.stephanehess.me.uk
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