The invention belongs to the technical field of
organic matter screening, and particularly relates to an optimal
selection method of an alternative standard substance in a standard-sample-free substance semi-quantitative process. The optimal
selection method comprises the following steps: acquiring response factors and various molecular fingerprints of the standard substance; for various molecular fingerprints of each standard sample, respectively calculating the similarity between each standard sample and other
standard samples by using a plurality of similarity
calculation methods, and selecting other
standard samples with the highest similarity as substitutes according to an obtained
similarity matrix; performing error evaluation to obtain an optimal circular
fingerprint type, an optimal structural key
fingerprint type, an optimal topological
fingerprint type and an optimal similarity calculation method; generating a composite fingerprint; and evaluating
response factor errors of the optimal structural key fingerprints, the circular fingerprints, the topological fingerprints and the composite fingerprints, and preferably selecting molecular fingerprints with the minimum errors and a similarity calculation method. According to the method, quantitative errors of different
molecular fingerprint types representing chemicals and a similarity calculation method are evaluated, so that the effect of minimizing the semi-quantitative error of the standard-sample-free substance is achieved.