Methodology for searching a large library of field sample spectra (Library X, y) using a generalized local adaptive fusion regression (LAFR) process for quantitative analysis of molecular based spectroscopic data (xnew) from a target sample of analytes, comprising:
- defining LAFR process parameters, including the number of library samples to retain in a decimation step, the number of calibration clusters to form, and the number of fundamental parameters to use;
- applying a decimation step to the library to reduce the library to most N spectrally similar to target sample, and to perform an outlier check to remove reduced library components for which the target sample is an outlier;
- forming linear calibration sets defined by the LAFR process parameters;
- performing an outlier check to remove linear calibration sets for which the target sample is an outlier;
- using ISUx and ISUy sample-wise similarities to mine the library of field sample spectra with reference amounts for a local training set explicitly matrix-matched to the target prediction sample;
- forming a prediction model formed with the local training set;
- and
- using the prediction model to predict the quantitative analysis of a target sample,
- where ISUx and ISUy sample-wise similarities comprise indicators of system uniqueness (ISU) to assess the degree of matrix matching between reference samples and the target sample.