Figure 5.

(A) Cumulative variability (%) explained by principal components of stable hand configurations (from manual annotation). Data points overlap for Principal Component(PC) 1 and higher order PCs. (B) Comparison of manually versus automatically annotated data. Plot of variance explained by principal components analysis of stable hand configurations: Variance explained of all principal component calculated for manually classified Acheulean percussion events (blue), Acheulean light percussion events (black) and Oldowan percussion events (red) plotted versus corresponding principal components of automatically annotated Acheulean (triangle) and Oldowan (circle) percussion-like events. E.g. the curve with black triangles, shows the principal components from 1 to 18 of the Acheulean light percussion events extracted by manual annotation (as horizontal position of the black triangle) versus the corresponding principal components from 1 to 18 for the automatically extracted percussion events (as vertical position of the black triangle). Note: automatic annotation did not distinguish between light percussion and percussion events. Correlation coefficients were greater 0.95 for all curves confirms that manual and automatic annotation yield very similar results.