Relative Compromise of Statistical Databases

Statistical databases are databases in which only statistical type of queries are allowed. The results of the statistical queries are intended for statistical use only. However, it has been shown that using only statistical queries it is often possible to infer an individuals's value of a protected field (e.g, using various types of trackers). In such a case we say that the database has been (positively) compromised. Various types of compromise have been studied but until now attention has centred on the inference of exact information from permitted queries. In this paper we introduce a new type of compromise, the 'relative' compromise: a set of records is relatively compromised with respect to a field X if the relative order of magnitude of the X-values of the set is known. This paper shows that even when exact information is protected, relative information may be accessible. We consider several sets of conditions under which this compromise can occur using SUM type of queries of fixed query set size, as well as some of the possible consequences of relative compromise. Disciplines Physical Sciences and Mathematics Publication Details Miller, M and Seberry, J, Relative compromise of statistical databases, ACSC12 and The Australian Computer Journal, 21(2), 1989, 56-61. This journal article is available at Research Online: http://ro.uow.edu.au/infopapers/1036 Relative compromise of statistical databases M. Miller Department of Mathematics, Statistics and Computing Science, University of New England, Annidale, NSW J. Seberry Department of Computer Science, University College, ADFA, Canberra, ACT Statistical databases are databases in which only statistical type of queries are aUowed The results of the statistical queries are intended for statistical use only. However, it has been shown that using only statistical queries it is often possible to infer an individlUll's value of a protected fleW (e.g., using various types of trackers), In such a case we say that the database has been (positively) compromised Various types of compromise have been studied but until now attention has centred on the inference of exact information from pennitted queries. In this paper we introduce a new type of compromise, the 'relative' compromise: a set of records is relatively compromised with respect to a field X if the relative order of magnitude of the X -values of the set is known This paper shows that even when exact infonnation is protected, relative infonnation may be accessible. We consider several sets of conditions under which this compromise can occur using SUM type of queries of fixed query set size, as well as some of the possible consequences of relative compromise.