Reviewed ou2018optimal
This commit is contained in:
		@ -44,7 +44,10 @@
 | 
				
			|||||||
      \cite{primault2015time} & (sequential) & & & & & & \\ \hdashline
 | 
					      \cite{primault2015time} & (sequential) & & & & & & \\ \hdashline
 | 
				
			||||||
 | 
					
 | 
				
			||||||
      \hyperlink{gursoy2018differentially}{\textbf{\emph{DP-Star}}} & finite & batch & global & user & linkage & perturbation & differential \\
 | 
					      \hyperlink{gursoy2018differentially}{\textbf{\emph{DP-Star}}} & finite & batch & global & user & linkage & perturbation & differential \\
 | 
				
			||||||
      \cite{gursoy2018differentially} & (sequential) & & & & & (Laplace) & privacy \\
 | 
					      \cite{gursoy2018differentially} & (sequential) & & & & & (Laplace) & privacy \\ \hdashline
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					      \hyperlink{ou2018optimal}{\textbf{\emph{FGS-Pufferfish}}} & finite & batch & local & event & dependence & perturbation & differential \\
 | 
				
			||||||
 | 
					      \cite{ou2018optimal} & (sequential) & & & & (temporal) & (Laplace) & privacy \\
 | 
				
			||||||
 | 
					
 | 
				
			||||||
      \midrule
 | 
					      \midrule
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
				
			|||||||
@ -1310,6 +1310,16 @@
 | 
				
			|||||||
           Accessed on November 11, 2020}
 | 
					           Accessed on November 11, 2020}
 | 
				
			||||||
}
 | 
					}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					@article{ou2018optimal,
 | 
				
			||||||
 | 
					  title     = {An optimal pufferfish privacy mechanism for temporally correlated trajectories},
 | 
				
			||||||
 | 
					  author    = {Ou, Lu and Qin, Zheng and Liao, Shaolin and Yin, Hui and Jia, Xiaohua},
 | 
				
			||||||
 | 
					  journal   = {IEEE Access},
 | 
				
			||||||
 | 
					  volume    = {6},
 | 
				
			||||||
 | 
					  pages     = {37150--37165},
 | 
				
			||||||
 | 
					  year      = {2018},
 | 
				
			||||||
 | 
					  publisher = {IEEE}
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
@inproceedings{ozccep2015stream,
 | 
					@inproceedings{ozccep2015stream,
 | 
				
			||||||
  title        = {Stream-query compilation with ontologies},
 | 
					  title        = {Stream-query compilation with ontologies},
 | 
				
			||||||
  author       = {{\"O}z{\c{c}}ep, {\"O}zg{\"u}r L{\"u}tf{\"u} and M{\"o}ller, Ralf and Neuenstadt, Christian},
 | 
					  author       = {{\"O}z{\c{c}}ep, {\"O}zg{\"u}r L{\"u}tf{\"u} and M{\"o}ller, Ralf and Neuenstadt, Christian},
 | 
				
			||||||
 | 
				
			|||||||
							
								
								
									
										104
									
								
								text/main.tex
									
									
									
									
									
								
							
							
						
						
									
										104
									
								
								text/main.tex
									
									
									
									
									
								
							@ -98,110 +98,6 @@
 | 
				
			|||||||
\input{theotherthing/main}
 | 
					\input{theotherthing/main}
 | 
				
			||||||
\input{conclusion/main}
 | 
					\input{conclusion/main}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
% An Optimal Pufferfish Privacy Mechanism for Temporally Correlated Trajectories
 | 
					 | 
				
			||||||
% - microdata
 | 
					 | 
				
			||||||
% - finite (sequential)
 | 
					 | 
				
			||||||
% - batch
 | 
					 | 
				
			||||||
% - dependence (temporal)
 | 
					 | 
				
			||||||
% - local
 | 
					 | 
				
			||||||
% - event
 | 
					 | 
				
			||||||
% - differential privacy
 | 
					 | 
				
			||||||
% - perturbation (randomized response, Laplace)
 | 
					 | 
				
			||||||
\hypertarget{ou2018optimal}{Ou et al.}~\cite{ou2018optimal}
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
\emph{FGS-Pufferfish}
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
temporally correlated trajectory data
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
First, a Laplace noise mechanism is realized through geometric sum of noisy Fourier coefficients of temporally correlated daily trajectories. 
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
We achieve better data utility for a given privacy budget by solving a constrained optimization problem of the noisy Fourier coefficients via the Lagrange multiplier method.
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
generation of Laplace noise via the Fourier coefficients' geometric
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
We present an analytical formula of the optimized Fourier coefficients noise for the constrained optimization problem of achieving a better data utility for a given privacy budget. 
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
We provide theoretical analysis of the data utility and privacy, as well as the posterior-to-prior knowledge gain of an adversary.
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
we quantify the temporal correlation in a rigorous mathematics way. 
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
by adding noise to the Fourier coefficients through geometric sum. 
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
The discrete Fourier transform transforms a user's daily trajectory
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
into a set of sine and cosine waves
 | 
					 | 
				
			||||||
of different frequencies and corresponding Fourier coefficients 
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
In this paper, we assume that both the real part and the imaginary part of the Fourier coefficient follow the same Gaussian distribution 
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
The constrained optimization problem is a strategy of finding the local extrema (maxima and minima) of a function f (b) subject to equality constraint g(b) = 0
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
The user's mobility pattern can be described by the conditional probability of the next i-th location from the current n-th location
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
A user's temporal correlation depicts the relation
 | 
					 | 
				
			||||||
between two locations at current time slot tn and its following i-th time slots tn+i
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
the Pufferfish secrets set consists of temporal correlations of all users
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
A correlation secrets pair consists of two temporal correlations of any two users in the same database
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
the Fourier coefficients of the temporal correlation are closely related to those of the daily trajectory. 
 | 
					 | 
				
			||||||
Thus it is natural to add noise to the Fourier coefficients of the trajectory
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
we propose to optimize the Fourier coefficients noise for the problem of temporal correlation privacy.
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
First, we add the noise in the Fourier coefficients
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
the noisy temporal correlation is obtained from the noisy daily trajectory
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
we propose to achieve the optimal data utility for a given privacy budget
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
Here we consider two utilities, including the location utility and the correlation utility
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
For the location utility, we want the average noisy location deviates from its raw location as small as possible
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
The correlation utility is the average of the deviation of the noisy correlation from its raw value
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
Our goal is to prevent an adversary from mining a user's privacy through analyzing the user's temporal correlation based on the adversary’s prior knowledge about the user.
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
First, we define the constrained optimization problem of achieving a better data utility for a given privacy budget given by the Laplace scale parameter
 | 
					 | 
				
			||||||
Next, we solve the constrained optimization problem via the LM method and obtain the optimal obtained Laplace scale parameter for the noisy Fourier coefficients
 | 
					 | 
				
			||||||
Then, the FGS-Pufferfish privacy mechanism adds noise to the Fourier coefficients and obtain the noisy Fourier coefficients
 | 
					 | 
				
			||||||
At last, we obtain the sanitized daily trajectories with the noisy Fourier coefficients 
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
we design an algorithm to release temporally correlated trajectories in order to protect individuals' privacy. 
 | 
					 | 
				
			||||||
Because our goal is to protect the temporal correlation of a user’s daily trajectory, we first calculate the Fourier coefficients of a daily trajectory which is related to the Fourier coefficients of its temporal correlation.
 | 
					 | 
				
			||||||
Then, to achieve the Laplace distribution of the noisy temporal correlation through the Fourier coefficients noise mechanism, i.e., adding noise to Fourier coefficients, with following the geometric distribution.
 | 
					 | 
				
			||||||
Furthermore, we obtain the optimal Laplace scale parameters for the noisy Fourier coefficients. Finally, we use IDFT to obtain the noisy loca- tions of the sanitized daily trajectory
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
We propose a Laplace noise mechanism based on the noisy Fourier coefficients' geometric sum, satisfying Pufferfish privacy, i.e., the FGS-Pufferfish privacy mechanism, to protect the temporal correlation of a user's daily trajectories. 
 | 
					 | 
				
			||||||
The optimal noisy Fourier coefficients are obtained by solving the constrained optimization problem via the LM method to achieves a better data utility for a given privacy budget. 
 | 
					 | 
				
			||||||
Experiments with both simulated and real-life data show that our FGS-Pufferfish privacy mechanism achieves better data utility and privacy compared to the existing approach.
 | 
					 | 
				
			||||||
Although we only deal with daily trajectories with a constant time interval, our proposed mechanism can be readily modified for time-series data with irregular time intervals
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
\backmatter
 | 
					\backmatter
 | 
				
			||||||
 | 
					
 | 
				
			||||||
\bibliographystyle{alpha}
 | 
					\bibliographystyle{alpha}
 | 
				
			||||||
 | 
				
			|||||||
		Reference in New Issue
	
	Block a user