User`s guide

Representing Data in the GUI
frequency-domain signals (see the fft reference page), the Fourier transforms
are computed a s discrete Fourier transforms (DFTs) for this sampling
interval. In addition, the sampling instantsareusedtosetthehorizontal
axis on time plots.
Sampling In
terval in the Import Data dialog box
Specifying
Estimation and Validation Data
To avoid ove
rfitting, you should use independent data sets to estimate and
validate yo
ur model.
In the Syste
mIdentification Tool GUI, Working Data refers to estimation
data. Simil
arly, Validation Data refers to the data set you use to validate a
model. For
example, when you plot the model output and residual-analysis
plots, the
input to the model is the input signal from the validation data set.
These plot
s compare model output to the measured output in the validation
data set.
To specif
y Working Data, d rag and drop the corresponding data icon into the
Working D
ata rectangle, as shown in the following figure.
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