Extended Data Fig. 10: Principal Component Analysis of Background-Subtracted Spectra.
From: Nanoscale imaging of phonon dynamics by electron microscopy
a, b, Raw background subtracted spectra in Si and QD plotted with PCA reconstructed data, respectively. c, Scree plot of cumulative explained variance showing 10 eigenvector decomposition with negligible explained variance after the first 3 eigenvectors. Therefore, the first 3 eigenvectors were chosen for the decomposition giving a cumulative explained variance of 92.8%. PCA reconstructed plots in a and b show that 3 eigenvectors sufficiently smoothen the data without any loss of features.
