VFVrPQ / LDP

Reproduce the mechanism mentioned in the 2017 paper.Implementation of Local Differential Private (LDP) mechanisms, just for fun.

LDP

Reproduce the mechanism mentioned in the 2017 paper.Implementation of Local Differential Private (LDP) mechanisms, just for fun. The experiment is based on a 2017 paper named "Locally Differentially Private Protocols for Frequencey Estimation".

Two steps:

1. Verifying Correctness of Analysis: DE,SUE,OUE,SHE,BLH,OLH;
2. Towards Real-world Estimation: RAPPOR(wait),BLH,OLH.

How to run

$ python3 main.py

Verifying Correctness of Analysis

numerical/analytical values of $Var[\tilde{c}(i)]$

Compare to Table 2 and Fig. 1($n=10000$) to verify the code.

1. Vary $\varepsilon$,$\varepsilon=0.5,1,1.5,...,5$:
   • DE: $d=2,4,16,128,2048$;
   • OUE;
2. Vary $\varepsilon$,$\varepsilon=0.5,1,1.5,...,5$, fixing $d=2^{10}$:
   • DE, SHE, SUE, OUE, BLH, OLH.

Reproduced figures

Comparing empirical and analytical variance

1. Vary $d$(fixing $\varepsilon=4$), $d=2^2,2^4,...,2^{14}$:(Runs too slowly when $d=2^{16}$)
   • DE, SUE, OUE;
   • SHE, BLH, OLH;
2. Vary $\varepsilon$(fixing $d=2^{10}$),$\varepsilon=0.5,1,1.5,...,5$:
   • DE, SUE, OUE;
   • SHE, BLH, OLH.

Reproduced figures

Towards Real-world Estimation

6.2.1 Figure 3

下载完数据./data/kosarak.dat后，

1. 模拟用户点击，根据不同的LDP协议发送给服务器；
2. 服务器收集了$n=8,000,000$,$d=41270$的数据后，使用aggregation，即estimate distribution（每个网页都要估计）；
3. 取前30个最高频度的计算平均方差。

写了drawFigure3.py，但是运行速度太慢了。 No idea yet.

datasets

./data/kosarak.dat.gz is from: http://fimi.uantwerpen.be/data/