Russian Dolls

Set Tversky and 
Count subsequent proximities that are 1.0 (or near 1.0) in common between compounds, in both directions – asymmetrically. The counts form an asymmetric matrix of proximities.
Perform a clustering on the proximity matrix, symmetrically on either of the one-way near-neighbor tables, or asymmetrically on the entire matrix.

Set Tversky and 