Incorporating Chemical Band-Assignment in near Infrared Spectroscopy Regression Models

Abstract

In this paper, we present an approach for incorporating chemical band assignment information in regression models between spectra and constituents. It is shown how the matrices in this L-shaped data structure can be combined and give direct information of the relationships between theoretical chemical band assignment, spectral wavelengths and the responses. The chosen application is NIR spectroscopic measurements of canola seeds. Variable selection based on partial least squares regression using jack-knifing within a cross-model validation (CMV) framework is applied for removing non-relevant spectral regions. Extended multiplicative scatter correction was applied as a spectral pre-treatment to remove physical scatter effects in the spectra. The results show a high degree of correspondence between the objectively found wavelength bands from CMV and the reported chemical interpretation found in the literature.

Keywords

PLS regression cross-model validation band assignment extended multiplicative scatter correction fatty acids interpretive spectroscopy

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