Hi,
Does Vensim do a similar process/steps to calibrate a stock and a flow variable?
Shall I am aware something when I calibrate either a stock/flow variable?
optimize-calibration
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Re: optimize-calibration
Sorry, I do not understand what you want to do.
Have you looked at the help system for calibration?
Have you looked at the help system for calibration?
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Re: optimize-calibration
There's no difference, except with respect to Kalman Filtering. https://www.vensim.com/documentation/ref_kalman.htm
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Re: optimize-calibration
Tom, thanks a lot for your reply.
If we do calibration continuously (maybe 24 hours), does it mean we will get
almost nil payoff?
or
does Vensim absolutely help us to get almost nil payoff?
Could you please explain of how to create Kalman-filter file (*.prm)?
If we do calibration continuously (maybe 24 hours), does it mean we will get
almost nil payoff?
or
does Vensim absolutely help us to get almost nil payoff?
Could you please explain of how to create Kalman-filter file (*.prm)?
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Re: optimize-calibration
It depends on the model you are trying to calibrate. Large models might never calibrate fully.
Have you checked the Vensim help system?
http://www.vensim.com/documentation/ind ... ?23625.htm
Advice to posters seeking help (it really helps us to help you)
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Re: optimize-calibration
I am trying to calibrate a stock model (fluctuated values depend on precipitation) and
I have found it's hard to get fully calibrate.
The model itself contains only less than 35 variables.
I have found it's hard to get fully calibrate.
The model itself contains only less than 35 variables.
Re: optimize-calibration
35 parameters, or 35 variables in total?
If the model doesn't fit the data after you've extensively explored the parameter space, there are some generic possibilities:
- model structure is wrong or incomplete somehow
- data has systematic errors
- noise has moved the system state
If the model doesn't fit the data after you've extensively explored the parameter space, there are some generic possibilities:
- model structure is wrong or incomplete somehow
- data has systematic errors
- noise has moved the system state
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Re: optimize-calibration
Hi Tom,
after applying Kalman filter, I got a better position.
Thanks.
after applying Kalman filter, I got a better position.
Thanks.