CIF: Small: Privacy and Utility of Databases: An Information-Theoretic Approach

信息技术和电子通信迅速应用于人类活动的各个领域，包括商业、医学和社交网络。随之而来的是无数大型集中式可搜索数据存储库的出现，使得通过数据关联(无意或恶意设计)泄露私人信息成为一个重要而紧迫的社会问题。保持这些数据源的有用性，同时提供必要的隐私保障，是一个重要的悬而未决的问题。这一问题推动了对总体分析框架的需求，该框架可以明确地告诉我们私有数据的安全性(隐私)，同时仍然为多个合法信息消费者提供有用的利益(效用)。本研究开发了一个统一的框架来研究效用与隐私的权衡，而不考虑数据源的类型或扰动的方法。使用率失真理论中的技术和结果对数据源进行建模，开发与应用无关的效用和隐私度量，并开发用于处理外部知识问题的辅助信息模型。该框架适用于单查询数据源模型，并扩展为研究多查询模型的效用-隐私权衡。还研究了连续披露问题，该问题借鉴了连续求精中的经典结果，以发展在多个查询下不会导致额外信息损失的条件。开发的通用框架包括工具和技术，以弥合信息论模型和当前方法以及计算机科学中占主导地位的理论框架之间的差距。

Information technology and electronic communications have been rapidly applied to every sphere of human activity, including commerce, medicine and social networking. The concomitant emergence of myriad large centralized searchable data repositories has made "leakage" of private information via data correlation (inadvertently or by malicious design) an important and urgent societal problem. Maintaining the usefulness of these data sources while also providing necessary privacy guarantees is an important unsolved problem. This problem drives the need for an overarching analytic framework that can tell us unequivocally how safe private data can be (privacy) while still providing useful benefit (utility) to multiple legitimate information consumers.This research develops a unified framework to study the utility-privacy tradeoff irrespective of the type of data source or method of perturbation. Techniques and results from rate-distortion theory are used to model data sources, develop application independent utility and privacy metrics, and develop a side-information model for dealing with questions of external knowledge. The framework, applicable for single query data source models, is extended to study the utility-privacy tradeoffs for multiple-query models. Also studied is a successive disclosure problem which draws on classic results in successive refinement to develop the conditions under which multiple queries result in no additional information loss. The universal framework developed includes tools and techniques to bridge the gap between the information-theoretic model and current approaches and the dominant theoretical framework in computer science.