Pearson Linear Correlation (x1-x)v1- No obvious p(x,y) relationship? X -x A medium direcl relationship? x Input A strong, inverse relationship a Were shifting the expression profiles down(subtracting the means)and scaling by the standard deviations (i.e. making the data have mean =0 and std= 1) a Always between-1 and +1(perfectly anti-correlated and perfectly correlated) 11Pearson Linear Correlation ◼ We’re shifting the expression profiles down (subtracting the means) and scaling by the standard deviations (i.e., making the data have mean = 0 and std = 1) ◼ Always between –1 and +1 (perfectly anti-correlated and perfectly correlated)      = = − − − − = = = = n i i n i i n i i n i i i n i i y n y x n x x x y y x x y y 1 1 ( ) ( ) ( )( ) ( , ) 1 2 1 2 1  x y 11