User`s guide

3 Linear Model Identification
3 Click E stimate to open the ARX Model S tructu re Selection window, which
displays the model performance for each combination of model param eters.
The following figure shows an example plot.
4 Select a rectang le that represents the optimum param eter combination and
click Insert to estimates a model with these parameters. For information
about using this plot, see “Selecting Model Orders from the Best ARX
Structure” on page 3-55.
This action adds a new model to the Model Board in the System
Identification Tool GUI. The default name of the parametric model contains
the model type and the number of poles, z eros, and delays. For exa mple,
arx692 is an ARX model with n
a
=6, n
b
=9, and a delay of two samples.
5 Click Close to close the ARX Model Structure Selection window.
After estimating model orders and d elay s, use these values as initial guesses
for estimating other model structures, as described in “How to Estim ate
Polynomial Models in th e GUI” on page 3-57.
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