Reversible Gap Derivatives and Their Integration

Higher-order gap derivatives are sometimes avoided as a preprocessing method for multivariate calibration despite their numerous advantages. One reason they are avoided is the difficulty in interpreting the complex processed spectra and the regression vectors that arise from common calibration procedures like principal components regression or partial least squares regression. In addition to retrieving zero-order spectral information via numerical integration, the method presented in this report is also extended to the integration of the accompanying regression vectors to aid in the interpretation of multivariate calibration models. 11 references (Publisher abstract modified)