Spectra residuals, Spectra residuals too big, Spectra residuum – BUCHI NIRCal User Manual
Page 200: 81 spectra residuals, 82 spectra residuals too big, 83 spectra residuum

NIRCal 5.5 Software Manual
200
NIRCal 5.5 Manual, Version A
3.18.81
Spectra Residuals
Description
The RMSD (Root Mean Squared Deviation) of the spectra residuum.
Use
To look at residual outlier.
Method
PCR / PLS / Cluster (CLU) / SIMCA
Matrices ID
41
Tip
Special tip to optimize the calibration
Details
The secondary PCs take no effect.
Formula
Related Topic
X-PRESS
,
Spectra Residuum
Indicates the difference of the pretreated spectra and the reconstructed spectra with the number of
primary PCs.
For the application the allowed residual is in most cases: 2x C-Set maximum residual. The default
blow up limit of 2 can be adjusted by the user.
3.18.82
Spectra Residuals too big
Description
Number of spectra with too big residual.
Use
Additional information for primary PCs selection or for outlier search.
Method
PCR / PLS / Cluster (CLU) / SIMCA
Matrices ID
54
Tip
The number of spectra with residual too big should be 0.
Details
The allowed residual is = 2* max. C-Set residual. Using this calculation only
V-Set spectra can be out of the limit.
2 is the default of residual blow up, can be edited by the user.
Related Topic
Residuals
,
Primary PCs
In a good calibration all spectra should fall within the allowed residual limits, so it should be zero in this
window.
3.18.83
Spectra Residuum
Description
Difference spectra between the pretreated spectra and the reconstructed
spectra.
Use
See where (wavelength, spectra) the major differences are.
Method
PCR / PLS / Cluster (CLU) / SIMCA
Matrices ID
9
Tip
To see that the C-Set spectra are not overfitted open this plot twice. In the
first set the visibility to the C-Set spectra, in the other set the visibility to the
V-Set spectra. The two sets should be similar.
Details
Related Topic
Loadings
,
Pretreated Spectra
,
X-PRESS
,
Reconstructed Spectra
The spectra residuum shows the difference spectrum for all pretreated spectra and the corresponding
reconstructed spectra calculated with the number of primary principal components. The size of these
difference spectra should be roughly the same for C- and V-Set, when the correct number of primary