User`s guide

Identifying State-Space Models
5 Click Estimate to open the Model Order Selection window, which
displays the relative measure of how much each state contributes to the
input-output behavior of the model (log of singular values of the covariance
matrix). The f ollowing figure shows an example plot.
6 Select the rectangle that represents the cutoff for the states on the left that
provide a significant contribution to the input-output behavior, and click
Insert to estimate a model with this order. Red indicates the recommended
choice. States 1 and 2 provide the most significant contribution. The
contributions to the right of state 2 drop significantly. For information
about using the Model Order Selection window, see “Using the Model Order
Selecti on Window” on p age 3-83.
This action adds a new model to the Model Board in the System
Identification To ol GUI. The default name of the parametric model
combines the string
n4s and the selected model order.
7 Click Close to close the Model Order Selection window.
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