Differentially Private Quantiles with Smaller Error

Neural Information Processing Systems 

In the approximate quantiles problem, the goal is to output mquantile estimates, the ranks of which are as close as possible to m given quantiles 0 q1 qm 1. We present a mechanism for approximate quantiles that satisfies ε-differential privacy for a dataset of n real numbers where the ratio between the distance between the closest pair of points and the size of the domain is bounded by ψ.