Dynamic Localized SNV, Peak SNV, and Partial Peak SNV: Novel Standardization Methods for Preprocessing of Spectroscopic Data Used in Predictive Modeling

Figure 8

Cross validation results for (a) SNV, (b) Dynamic Localized SNV, (c) Peak SNV, and (d) Partial Peak SNV preprocessed spectra in the regression case of the friction modifier additive. The reference values were measured by HPLC-QToF. Red dots indicate prediction of calibration samples, and blue dots represent prediction of the hold-out validation samples. The dashed arrow in (a) indicates the increasing degradation of the samples with increasing time as the friction modifier additive concentration gets lower.

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