Anonymization Device for Preserving Utility of Data and Method thereof

摘要

Disclosed is an anonymizing device. The anonymizing device includes a generalization unit generalizing a record by expanding a range of data of a quasi-identifier among the data of the record about an individual which comprises at least one piece of data individually classified by the quasi-identifier or sensitive attribute. The generalization unit generalizes that a first generalization level of the generalized record is equal to or less than a predetermined value. The generalized data of each of the generalized record has a second generalization level determined in accordance with the ratio of difference between the maximum and minimum values of a numerical attribute domain and the difference of the maximum and minimum values of the data generalized when the quasi-identifier is a numerical attribute. When the quasi-identifier is a categorical attribute, each generalized data of the generated record has a second generalization level determined in accordance with the ratio of the value in which 1 is subtracted from the number of leaf nodes of a classification tree about the categorical attribute to a value in which 1 is subtracted from the leaf node of the node corresponding to the generalized data in the classification tree. The first generalization level is defined as the value in which a sum of the second generalization level is divided by a number (n) of the quasi-identifier. The predetermined value is a real number in a range of 0 to 1. The purpose of the present invention is to provide the anonymizing device preventing anonymized data from being excessively generalized.