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Problem with estimation of MDCNEV model

Ask questions about how to estimate models and how to change your settings for estimation.
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eeshanbhaduri01
Posts: 3
Joined: 03 Dec 2020, 12:26

Problem with estimation of MDCNEV model

Post by eeshanbhaduri01 »

I am currently working on an MDCNEV model but keep on getting the error message which reads -

Error in if (all(testL == 0)) stop("\nAll observations have zero probability at starting value for model component \"", :
missing value where TRUE/FALSE needed
Traceback---
3.
apollo_mdcnev(mdcnev_settings, functionality)
2.
apollo_probabilities(apollo_beta, apollo_inputs, functionality = "validate")
1.
apollo_estimate(apollo_beta, apollo_fixed, apollo_probabilities,
apollo_inputs)

I have tried the possible solutions suggested in Apollo website FAQs but those do not seem to work. Currently, I am working with the simplest possible specification of the model (=starting values) with alpha_base(=0), gamma for all modes(=1), delta for all modes(=1), sigma(=1), panel(=0), nesting coefficient theta (=0,1)

Let me know if anybody can help. Thanks in advance.

Best,
Eeshan
dpalma
Posts: 190
Joined: 24 Apr 2020, 17:54

Re: Problem with estimation of MDCNEV model

Post by dpalma »

Hi Eeshan,

It is hard to diagnose the problem without looking at the code. If you post your code, we might be able to find the issue.

Best wishes
David
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