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Measurement equation include parameters to be estimated

PostPosted: Thu Dec 01, 2016 5:55 am
by ZBCPA
Dear Johannes,

Could I ask you, in Bayesian estimation, if parameters to be estimated appear in measurement equation, would that be any problem?

Thanks in advance.

Kind regards,
Huan

Re: Measurement equation include parameters to be estimated

PostPosted: Thu Dec 01, 2016 1:12 pm
by jpfeifer
Dear Huan,
why should that be a problem? A case like this occurs whenever you want to estimate the mean growth rate in an observation equation using first differences.

Re: Measurement equation include parameters to be estimated

PostPosted: Mon Dec 12, 2016 4:10 am
by ZBCPA
jpfeifer wrote:Dear Huan,
why should that be a problem? A case like this occurs whenever you want to estimate the mean growth rate in an observation equation using first differences.


Many thanks Johannes.

In my model , I have financial friction but do Not have a good corresponding financial data. If I use linear detrended interest rate spread data as an "instrument" , and set a new parameter measuring the volatility difference between data and model variable in measurement equation , maybe also put an measurement error there, shown as below
Code: Select all
interest rate spread_obs= (constant x  )* model financial friction variable + measurement error
,
(model is log-linearized)
Then estimate the constant x (only appears in measurement equation) and standard deviation of measurement error, would that be a problem?

Kind regards,
Huan

Re: Measurement equation include parameters to be estimated

PostPosted: Mon Dec 12, 2016 6:47 am
by jpfeifer
This is hard to tell. It looks good to me. But to be on the safe side, I would test identification, if you add measurement error.

Re: Measurement equation include parameters to be estimated

PostPosted: Thu Dec 29, 2016 10:15 am
by ZBCPA
jpfeifer wrote:This is hard to tell. It looks good to me. But to be on the safe side, I would test identification, if you add measurement error.


Dear Johannes,

Happy new year!

Could I ask further about testing identification?

1. In Dynare, the only way to test identification is command
Code: Select all
identification;
after estimation?
2. If the model passes this identification check, does that mean there is No identification problem?

Kind regards,
Huan

Re: Measurement equation include parameters to be estimated

PostPosted: Sun Jan 01, 2017 8:02 am
by jpfeifer
1. No, you can call identification before, after or even without estimation. All that is needed is are a
Code: Select all
varobs
statement and an
Code: Select all
estimated_params
block
2. It's somewhat more complicated. The way to check identification is local. If you pass the identification checks, that only tells you the current point is fine, but quite often that extends to (almost) the whole parameter range.