Shift and intensity modeling in spectroscopy—general concept and applications

Multivariate analysis and calibration in spectroscopy have been widely used in many fields of applications in recent years. The number of components to use in such applications for sufficiently describing the spectra is dependent on the stability of positions of the peaks of interest. Unwanted shifts give rise to a more complex model, i.e., more components. Various kinds of shift correction can be applied as preprocessing tools to cope with these effects. In this paper we describe a general concept of how to model intensity (peak height) and position as separate phenomena. We described methods and theory from image modeling, and apply them on one-dimensional signals such as traditional Raman spectroscopy.