1,300 research outputs found
Injecting Uncertainty in Graphs for Identity Obfuscation
Data collected nowadays by social-networking applications create fascinating
opportunities for building novel services, as well as expanding our
understanding about social structures and their dynamics. Unfortunately,
publishing social-network graphs is considered an ill-advised practice due to
privacy concerns. To alleviate this problem, several anonymization methods have
been proposed, aiming at reducing the risk of a privacy breach on the published
data, while still allowing to analyze them and draw relevant conclusions. In
this paper we introduce a new anonymization approach that is based on injecting
uncertainty in social graphs and publishing the resulting uncertain graphs.
While existing approaches obfuscate graph data by adding or removing edges
entirely, we propose using a finer-grained perturbation that adds or removes
edges partially: this way we can achieve the same desired level of obfuscation
with smaller changes in the data, thus maintaining higher utility. Our
experiments on real-world networks confirm that at the same level of identity
obfuscation our method provides higher usefulness than existing randomized
methods that publish standard graphs.Comment: VLDB201
Privacy-preserving mechanism for social network data publishing
Privacy is receiving growing concern from various parties especially consumers due to the simplification of the collection and distribution of personal data. This research focuses on preserving privacy in social network data publishing. The study explores the data anonymization mechanism in order to improve privacy protection of social network users. We identified new type of privacy breach and has proposed an effective mechanism for privacy protection
Active Re-identification Attacks on Periodically Released Dynamic Social Graphs
Active re-identification attacks pose a serious threat to privacy-preserving
social graph publication. Active attackers create fake accounts to build
structural patterns in social graphs which can be used to re-identify
legitimate users on published anonymised graphs, even without additional
background knowledge. So far, this type of attacks has only been studied in the
scenario where the inherently dynamic social graph is published once. In this
paper, we present the first active re-identification attack in the more
realistic scenario where a dynamic social graph is periodically published. The
new attack leverages tempo-structural patterns for strengthening the adversary.
Through a comprehensive set of experiments on real-life and synthetic dynamic
social graphs, we show that our new attack substantially outperforms the most
effective static active attack in the literature by increasing the success
probability of re-identification by more than two times and efficiency by
almost 10 times. Moreover, unlike the static attack, our new attack is able to
remain at the same level of effectiveness and efficiency as the publication
process advances. We conduct a study on the factors that may thwart our new
attack, which can help design graph anonymising methods with a better balance
between privacy and utility
Conditional adjacency anonymity in social graphs under active attacks
Social network data is typically made available in a graph format, where users and their relations are represented by vertices and edges, respectively. In doing so, social graphs need to be anonymised to resist various privacy attacks. Among these, the so-called active attacks, where an adversary has the ability to enrol sybil accounts in the social network, have proven difficult to counteract. In this article, we provide an anonymisation technique that successfully thwarts active attacks while causing low structural perturbation. We achieve this goal by introducing (k, Γ G,â„“) -adjacency anonymity: a privacy property based on (k, â„“) -anonymity that alleviates the computational burden suffered by anonymisation algorithms based on (k, â„“) -anonymity and relaxes some of its assumptions on the adversary capabilities. We show that the proposed method is efficient and establish tight bounds on the number of modifications that it performs on the original graph. Experimental results on real-life and randomly generated graphs show that when compared to methods based on (k, â„“) -anonymity, the new method continues to provide protection from equally capable active attackers while introducing a much smaller number of changes in the graph structure
Enumerative aspects of the Gross-Siebert program
We present enumerative aspects of the Gross-Siebert program in this
introductory survey. After sketching the program's main themes and goals, we
review the basic definitions and results of logarithmic and tropical geometry.
We give examples and a proof for counting algebraic curves via tropical curves.
To illustrate an application of tropical geometry and the Gross-Siebert program
to mirror symmetry, we discuss the mirror symmetry of the projective plane.Comment: A version of these notes will appear as a chapter in an upcoming
Fields Institute volume. 81 page
Complex Networks
An outline of recent work on complex networks is given from the point of view
of a physicist. Motivation, achievements and goals are discussed with some of
the typical applications from a wide range of academic fields. An introduction
to the relevant literature and useful resources is also given.Comment: Review for Contemporary Physics, 31 page
Minimal Algorithmic Information Loss Methods for Dimension Reduction, Feature Selection and Network Sparsification
We introduce a family of unsupervised, domain-free, and (asymptotically)
model-independent algorithms based on the principles of algorithmic probability
and information theory designed to minimize the loss of algorithmic
information, including a lossless-compression-based lossy compression
algorithm. The methods can select and coarse-grain data in an
algorithmic-complexity fashion (without the use of popular compression
algorithms) by collapsing regions that may procedurally be regenerated from a
computable candidate model. We show that the method can preserve the salient
properties of objects and perform dimension reduction, denoising, feature
selection, and network sparsification. As validation case, we demonstrate that
the method preserves all the graph-theoretic indices measured on a well-known
set of synthetic and real-world networks of very different nature, ranging from
degree distribution and clustering coefficient to edge betweenness and degree
and eigenvector centralities, achieving equal or significantly better results
than other data reduction and some of the leading network sparsification
methods. The methods (InfoRank, MILS) can also be applied to applications such
as image segmentation based on algorithmic probability.Comment: 23 pages in double column including Appendix, online implementation
at http://complexitycalculator.com/MILS
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