Visible to the public PrivBayes: Private Data Release via Bayesian Networks

TitlePrivBayes: Private Data Release via Bayesian Networks
Publication TypeJournal Article
Year of Publication2017
AuthorsZhang, Jun, Cormode, Graham, Procopiuc, Cecilia M., Srivastava, Divesh, Xiao, Xiaokui
JournalACM Trans. Database Syst.
Volume42
Pagination25:1–25:41
Date Publishedoct
ISSN0362-5915
KeywordsBayesian Network, Collaboration, compositionality, Data Sanitization, Differential privacy, Human Behavior, human factors, policy, privacy, pubcrawl, Resiliency, synthetic data generation
AbstractPrivacy-preserving data publishing is an important problem that has been the focus of extensive study. The state-of-the-art solution for this problem is differential privacy, which offers a strong degree of privacy protection without making restrictive assumptions about the adversary. Existing techniques using differential privacy, however, cannot effectively handle the publication of high-dimensional data. In particular, when the input dataset contains a large number of attributes, existing methods require injecting a prohibitive amount of noise compared to the signal in the data, which renders the published data next to useless. To address the deficiency of the existing methods, this paper presents PrivBayes, a differentially private method for releasing high-dimensional data. Given a dataset D, PrivBayes first constructs a Bayesian network N, which (i) provides a succinct model of the correlations among the attributes in D and (ii) allows us to approximate the distribution of data in D using a set P of low-dimensional marginals of D. After that, PrivBayes injects noise into each marginal in P to ensure differential privacy and then uses the noisy marginals and the Bayesian network to construct an approximation of the data distribution in D. Finally, PrivBayes samples tuples from the approximate distribution to construct a synthetic dataset, and then releases the synthetic data. Intuitively, PrivBayes circumvents the curse of dimensionality, as it injects noise into the low-dimensional marginals in P instead of the high-dimensional dataset D. Private construction of Bayesian networks turns out to be significantly challenging, and we introduce a novel approach that uses a surrogate function for mutual information to build the model more accurately. We experimentally evaluate PrivBayes on real data and demonstrate that it significantly outperforms existing solutions in terms of accuracy.
URLhttp://doi.acm.org/10.1145/3134428
DOI10.1145/3134428
Citation Keyzhang_privbayes:_2017