We introduce the problem of deceptive information retrieval (DIR), in which a user wishes to download a required file out of multiple independent files stored in a system of databases while \emph{deceiving} the databases by making the databases' predictions on the user-required file index incorrect with high probability. Conceptually, DIR is an extension of private information retrieval (PIR). In PIR, a user downloads a required file without revealing its index to any of the databases. The metric of deception is defined as the probability of error of databases' prediction on the user-required file, minus the corresponding probability of error in PIR. The problem is defined on time-sensitive data that keeps updating from time to time. In the proposed scheme, the user deceives the databases by sending \emph{real} queries to download the required file at the time of the requirement and \emph{dummy} queries at multiple distinct future time instances to manipulate the probabilities of sending each query for each file requirement, using which the databases' make the predictions on the user-required file index. The proposed DIR scheme is based on a capacity achieving probabilistic PIR scheme, and achieves rates lower than the PIR capacity due to the additional downloads made to deceive the databases. When the required level of deception is zero, the proposed scheme achieves the PIR capacity.

翻译：我们提出了欺骗性信息检索（DIR）问题，在该问题中，用户希望从存储在数据库系统中的多个独立文件中下载所需文件，同时通过使数据库对用户所需文件索引的预测以高概率出错来 *欺骗* 数据库。概念上，DIR 是私有信息检索（PIR）的扩展。在 PIR 中，用户下载所需文件而不向任何数据库泄露其索引。欺骗度量的定义为数据库对用户所需文件预测的错误概率减去 PIR 中对应的错误概率。该问题定义于随时间不断更新的时敏数据上。在所提出的方案中，用户通过以下方式欺骗数据库：在需求时刻发送 *真实* 查询以下载所需文件，并在多个不同的未来时间点发送 *虚假* 查询，以操纵每次文件需求发送每个查询的概率，数据库据此对用户所需文件索引进行预测。所提出的 DIR 方案基于达到容量的概率性 PIR 方案，由于为欺骗数据库而进行的额外下载，其速率低于 PIR 容量。当所需欺骗水平为零时，所提出方案达到 PIR 容量。