Figure 3

1-D PCA score plots for the principal components (PC 1, PC 2 and PC 3) for the external spike-in hybridization controls of the rat dataset. Symbols are color-coded according to the date of hybridization (A - M; see legend) and data from single arrays are overlaid on box plots that summarize the data in each date class. A subset of data points are labeled with both the date class abbreviation (A - M) and the hybridization number (1-137).