Subtract the mean
Compute the singular value decomposition (SVD)
Plot data in the transformed

$\tilde{x}=x-\bar{x}$
$b^T=\tilde{x}^T[v_1, v_2]$
$x' = b[v_1,v_2]$
Similarity s(x,y) Often between 0 and 1. Higher are more sililar
Dissimilarity d(x,y) Greater than 0. Lower means more similar


If you want to be sensitive to outliers use max-norm distance
Similarity measures