Real relative asymmetry compares the RA value of a particular space with the RA value for the root – the space at the bottom of a justified map – of a diamond-shaped system. RRA values will only be needed when comparing across systems of different sizes. This is an empirical way of normalising total depth.
Real Relative Asymmetry (RRA)
Sources
Hillier, B. & Hanson, J. (1984), The Social Logic of Space, Cambridge University Press: Cambridge. pp.111-113