Single-point baseline correction

Calibration design 22-sampIe mixture design Validation design leave-one-out cross-validation Preprocessing single-point baseline correction at 1100 nm Variable range 550 measurement variables 1100-2198 nra... 

Whether the transmittance of the baseline increases or decreases when a sample is inserted in the beam, it is often good practice to divide the transmittance spectrum by its maximum ordinate in a spectral region where the sample does not absorb before converting the spectrum to absorbance. (This operation is sometimes known as single-point baseline correction-, see Section 10.1.)... 

PCA was employed to classify the differences in the spectra for each local area spectrum of the spherulite. Consequently, 20 single spectra were extracted from 20 points of groups A-C, but for group D only five spectra were obtained as the amorphous area is limited (as shown in Figure 22.23c). All spectra in the region of 5500-3300 cm were subjected to a linear baseline correction and a second derivative pretreatment to highlight subtle differences in the spectral features among the spectra before the PCA calculations. 

---