1. A method for developing a calibration score matrix, comprising the steps of: providing a matrix of calibration spectra; generating N spectral matrices corresponding with N spectral regions of said calibration spectra, wherein N is an integer greater than or equal to two and wherein at least two of said N spectral regions are non-identical spectral regions; independently decomposing each of said N spectral matrices to yield N score matrices; independently selecting a plurality of factors for each of said N score matrices; concatenating said selected number of factors for each of said N score matrices, to generate a calibration score matrix, and estimating, with a spectrometer, a target property from a prediction matrix using said calibration score matrix, wherein said spectrometer comprises a base module, a communication bundle, and a sample module, wherein said communication bundle integrates said sampling module and said base module.