Some vector operations
Addition : 
Z
= X Y
Z
= X Yzi = xi + yivector Z is normalizedTerm to term mult : Z
= X Y
Z
= X Yzi = (xi * yi)1/2vector Z is not normalizedWeak contextualization G:
Z = X (X Y) = G(X,Y)
Z = X (X Y) = G(X,Y)าZ is X augmented by its mutual information with Yำ