Research on Trajectory Data Releasing Method via Differential Privacy Based on Spatial Partition

Algorithm 1

DPSD().

Input: original dataset , privacy budget

node amount of each area in partition

Output: after dividing

Initialize . Assign locations at each time of the

trajectory dataset to

For each , computing and location entropy for in

, determining order of Hilbert curve

Generate four Hilbert curves, for each curve

computing according to

and

select with probability

is proportional to

Output the optimal partition of at

Output the set