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LL(start) seems to ignore the weights

Report bugs or highlight issues with Apollo functions. At a minimum, please include the part of the output where you believe the bug is manifested. Ideally, please share your model file.
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raplam
Posts: 1
Joined: 19 Aug 2022, 12:04

LL(start) seems to ignore the weights

Post by raplam »

Hello,

I am estimating an MNL model with weights and was quite confused to observe that LL(0) and LL(start) were different, although all the initial values of my parameters were 0. I first thought that I had not properly understood the definition of LL(0) but after spending a bit of time in the source code, I believe that the reason is that LL(start) is calculated by ignoring the weights, while LL(0) accounts for them. I am not very familiar with the discrete choice models but I guess this is not desired. If it is desired, then a hint in the manual would be helpful for people like me...

That's all - thank you very much for your response and for this great package!

Raphaël
stephanehess
Site Admin
Posts: 974
Joined: 24 Apr 2020, 16:29

Re: LL(start) seems to ignore the weights

Post by stephanehess »

Raphael

thanks, this is indeed a bug in the output. We will fix it in 0.2.9

Stephane
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Stephane Hess
www.stephanehess.me.uk
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