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wtp space model

Ask questions about how to estimate models and how to change your settings for estimation.
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maa033
Posts: 41
Joined: 23 Jul 2020, 14:00

wtp space model

Post by maa033 »

Hi

We are estimating a model in wtp-space. The estimated parameters are sensitive to starting values, and we need to run robustness checks varying the starting values. Is there a command in apollo that automatically repeats the estimation of a model updating the starting values of the parameters?

We are aware of the apollo_searchStart command, but not sure that this solve our problem. What we need is, after having searched for and found the best starting values, a command that can verify that these starting values are producing a global optimum by testing for small deviations. And if we are not able to verify a global optimum, we need at least to check that we have a stable local optimum.

thank you in advance for your reply.

Best regards,
Margrethe
stephanehess
Site Admin
Posts: 1210
Joined: 24 Apr 2020, 16:29

Re: wtp space model

Post by stephanehess »

Margrethe

you can never know whether you found the global optimum as you cannot test all possible solutions.

What you could do re the below is write a loop with lots of starting values and carry out the full estimation from each of these

Stephane
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Stephane Hess
www.stephanehess.me.uk
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