Figure 6From: Comprehensive analysis of correlation coefficients estimated from pooling heterogeneous microarray dataInfluence of covariances and means of 19 groups on signs of the Pearson correlation coefficients obtained from the pooled expression data. (a) s ̄ xy = ∑ i 19 λ i s xy , i ; (b) d xy = ∑ i = 1 19 ∑ j = i + 1 19 λ i λ j ( x ̄ i − x ̄ j )( y ̄ i − y ̄ j ).Back to article page