ANONYMITY DETERMINATION SYSTEM AND ANONYMITY DETERMINATION METHOD

摘要

PROBLEM TO BE SOLVED: To determine whether or not anonymity of location information acquired in a time series is secured.SOLUTION: A anonymity determination system includes: a computer 10 provided with a computing unit 11 and a storage part 12; and a database 20 storing time series location information 21. The storage part 12 stores an anonymity index. The computing unit 11 creates a local achievability matrix that describes in components (i, j) "1" when a combination of i-th location information at a time of day t1 and j-th location information at a time of day t2 is achievable and "0" when it is not achievable with respect to the adjacent times of day t1, t2 in time series location information 21 and, when there is at least one row or column which is below an anonymity index among respective sums of rows and columns of the local achievability matrix, determines that anonymity has not been secured.SELECTED DRAWING: Figure 1