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It seems that the loglikelihood is basically zero for some households (while reasonable for others).
For instance, the first 25 loglikelihoods of kilometers traveled are as attached.
What would you suggest?
Thank you,
Chris
Loglikelihoods_2class_model.png (75.22 KiB) Viewed 3823 times
My apologies, see attached the LL for the combined model.
This LL should be equal to the following equation: LL_total = log(P_c0*(L_car_c0*L_pt_c0*L_other_c0) + P_c1*(L_Car_c1*L_pt_c1*L_Other_c1) whereby L is the likelihood.
The model successfully run in Biogeme, but I ran into problems when trying to add a c2 class (for households owning 2+ cars).
I then tried to replicate the model in Apollo (see code below).
Again, I am not entirely sure this code is correct as I am used to programming in Biogeme.
Thank you so much,
Chris
Attachments
Loglikelihoods_2class_model_inctotal.png (103.48 KiB) Viewed 3807 times
Last edited by ChrisDjie on 17 Aug 2023, 08:59, edited 1 time in total.
The entries with zero total likelihoods were all households that traveled many kilometers by motors/mopeds.
I thus excluded all kms by private motorized modes that are not cars.
The total likelihoods were never zero after this intervention.
The likelihoods of kilometers traveled by modes within a specific class, like carlike kms for households that do not own a car (c0), were sometimes zero though.
There is nothing weird or typical about the underlying entries.
The model now runs, which is an improvement, but the results say that the likelihood within one component is zero (which makes sense).
Depending on the starting values, this component is either in the no-car (c0) or car-owning (c1) class.
Please note that I already sucessfully ran this version of the model in Biogeme.
However, the model was too sensitive to the starting values, making it impossible to add another class (multiple cars, c2).
I was hoping that Apollo could help me fix the issue.
Good to know that the zero LLs within one class are okay.
When running the searchStart function, I get: "100 candidates removed due to non-finite starting LL. 0 remain."