In microarrays experiments, a serious limitation is the unreliability of low signal intensities data and the lack of reproducibility for the resulting ratios between samples and controls.
Fig. 4 PCA biplot (left) and PCA scree plot (right) using CLR transformed HHpXRF raw intensities data.
In the case of the present analysis, the main advantage of the dataset was clearly the availability of comparable task intensities data at the 4-digit occupation level.
Fig. 3 PCA biplot (left) and PCA scree plot (right) using CLR transformed HHpXRF raw intensities data: Mochica bichrome and Mochica polychrome ceramics (black dots), Coastal Cajamarca (gray diamonds) and Highland Cajamarca ceramics (gray triangles).
The analysis of raw intensities data transformed (CLR transformation) inside this group (notably for CaKα1, SrKα1, RbKα1 and YKα1 data) demonstrates the existence of two chemical sub-groups that are not directly related to the bichrome or polychrome ceramics (Fig. 4).
The intermediate classes often lie in between (see Figure 8 for results from three mice that include parametric changes in drop and air-blow intensities, Data from Mouse#1 is presented in A and B; Mouse#2 in C and D, and Mouse#3 in E and F, respectively).
