A data-swapping technique using ranks : a method for disclosure control

A data-swapping technique based on ranks is described and suggested as a possible approach to statistical disclosure control. The proposed method is intended to be applied to quantitative data and utilises the rank structure of disjoint subsets of an original data set; values of one subset are exchanged for values of other subsets. The procedure retains the validity of a sample on an intra-variate level but the association between pairs of variables is typically weakened. Theoretical and simulation results indicate that the proposed method performs reasonably well in the bivariate normal case.