]> Prevosti et al's (1975) distance

Prevosti et al's (1975) distance [Takezaki, N. 96] has a statistical property similar to that of Dr and is defined as

Cp = ∑ j r ∑ i m j x ij − y ij 2r Cp = {sum _j ^r sum _i ^{m_j} abs{x_ij - y_ij}} over 2r