Global Clustering Quality Coefficient Assessing the Efficiency of PCA Class Assignment
Figure 2
PC1 versus PC2 score plots associated with the GC-FTIR spectra of stimulant amphetamines (class M), hallucinogenic amphetamines (class T), and negatives (class N) for: (a) unprocessed spectra, (b) spectra preprocessed with the selective amplifier, (c) spectra preprocessed with the selective amplifier, and (d) spectra preprocessed with the amplifying selector. MC—center of the M cluster, TC—center of the T cluster, and NC—center of the N cluster.
