Metrohm Vision – Tutorial - Manual (Page 26)

1.6 Multilinear Regression 
NIRS Vision Tutorial – Operation 
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Perform Sample Selection
1. Click on Select  Apply Math.
2. In the Edit Sample Selection Parameters dialog box enter the
following settings:
 Selection Method Mahalanobis Distance in Principal Component
Space
 Math Treatment 2nd derivative
 Leave all other settings unchanged
3. Click on [OK].
4. In the Edit Math Properties dialog box in the Principal Components
ID Parameters tab set the following wavelength regions:
 Region 1
Minimum: 416
Maximum: 1080
 Region 2
Minimum: 1120
Maximum: 2484
 Cum Var. 95 %
 Click on [OK]
5. In the Edit Math Properties dialog box in the 2nd derivative tab set
the following values:
 Segment: 10
 Gap: 0
6. In the Sample Selection Options dialog box apply or confirm the
following settings:
 Find Outliers enabled
 Outlier Threshold 0.95
 Threshold Type Probability Level
 Find Redundant enabled
 By number of samples enabled
 Training Set 75 %
 Acceptance Set 25 %
 Click on [OK]
Vision now performs calculations according to the parameters defined in the
previous steps.