Figure 11
From: A novel Raman spectroscopic method for detecting traces of blood on an interfering substrate
A hierarchical approach to test for potential false positives. Raman spectral data obtained for an apparent bloodstain are statistically compared with Raman spectra obtained for a pure substrate material. Principal component analysis (PCA) score plots prepared using the first and second principal components demonstrate significant separation of the two classes of Raman spectra for blood stains on all substrates used.
