The OCNM algorithm is a block-based procedure that provides a binary decision function <i>h</i>(<b>x</b><SUB>t</SUB>) indicating whether <b>x</b><SUB>t</SUB> is a member of the MVS.  The algorithm requires the choice of a sparsity measure (a distance function) <i>h</i>(<b>x</b><SUB>t</SUB>).  We have implemented the OCNM algorithm for comparative purposes using the <i>n</i>th nearest neighbour distance as the sparsity measure.