STANDARDIZATION OF NEAR-INFRARED SPECTROMETRIC INSTRUMENTS

In this paper, two different approaches are studied for the standardiz ation of near-infrared spectrometric instruments, The first is a simpl e method based on a univariate slope/bias correction of the predicted values, The second approach proposed is the much more sophisticated pi ecewise direct standardization (PDS) based on a multivariate correctio n of spectra, Both standardization methods are applied to three differ ent data sets, and the results obtained are compared, In certain cases , the simple slope/bias correction approach yields results at least as good as those obtained by the PDS procedure. In other cases, the comp lex PDS procedure is required to obtain acceptable results, A diagnost ic tool is developed in order to decide whether the simple slope/bias correction approach can be applied instead of PDS.