The use of contact sampling in studies of association in vegetation

It is preferable to tabulate and analyse data with an unfolded contingency table where the ordered 'contact pairs' (i, j) and (j, i) are distinguished, rather than with a folded (triangular) table used previously. This, together with considerations of the treatment of data in which there are events of within-species 'contact pairs' (i.e. when j = i), forms the basis for recommending an 'optimal' strategy for examining tendencies for between-species association - optimal in the sense of both statistical efficacy and sampling mechanics. -from Authors