Figure 3

Relevance of gene expression variables to the top CCA features from the leukemia data set. The cross-loadings, indicating the relevance of each gene expression variable to the first two features extracted using regularized dual CCA, with regularization parameters τ _x = 0.9, τ _y = 0.3 (left panel), and PCA+CCA (right panel). The upper panels show the cross-loadings with the first feature, and the lower panels show the cross-loadings with the second feature. The variables are ordered along the genome and the vertical lines mark the chromosome boundaries. The cross-loadings for a gene expression variable measure the degree of linear relationship between the log₂ expression value of that variable and the respective copy number features. Hence, a higher (in absolute value) cross-loading indicates a stronger correlation between the variable and the copy number feature.