PerkinElmer SPECTRUM TWO N, User Manual

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62 . Spectrum Two N User's Guide
Compare
The Compare process estimates similarity between spectra by comparison with a reference
spectrum or spectra, and is used to confirm the identity of a sample. The results are
displayed on the Compare tab in the Viewing Area (Figure 40).
Figure 42 Compare tab
In this example, the spectrum has been confirmed to be the same as the reference
spectrum, where the Correlation was defined at 0.98. The Correlation result is greater than
0.99, where 1.00 would mean that the spectra were identical.
NOTE: For an example of a Report generated showing the Compare results, refer to
Reporting on page 75.
The parameters used in the Compare process are defined on the Setup Compare tabs.

Select Compare from the Setup menu to display the Setup Compare tabs.
On the Setup Compare References tab (Figure 41) you can load a single spectrum file or a
folder of spectra. Then set the Correlation and/or Discrimination thresholds to define the
Pass/Fail result.
Correlation expresses the degree of similarity between the spectra, where 1 is identical, and
0 is wholly unrelated. Discrimination ensures that the closest match is sufficiently separated
from the next closest match. Its value is the difference in the Correlation values of the first
two results on the Compare tab.
Only files or folders with Include enabled will be used in the Compare.
Figure 43 Setup Compare References tab