Facebook, Inc.

Shiyu Zhao

Bhupinder Singh Sethi

Yang Xia

Matthew K Choi

Nicholas Scott LaGrow

Systems, methods, and non-transitory computer-readable media can determine at least one survey to be presented to users of the social networking system, wherein the survey is targeted to a number of users at each time interval. A uniform distribution of users that may be surveyed is determined, wherein users in the uniform distribution are each assigned a numerical value. A sampling window that references a numerical range that is adjusted upon completion of each time interval is determined, wherein users that have been assigned a numerical value within the numerical range are eligible for the survey.

Systems and methods for surveying users

An multi-level privacy evaluation technology is described for increasing the performance of applications or services that experience high volumes of queries for data with privacy attributes. The multi-level privacy evaluation technology evaluates data using a subset of privacy policy rules and privacy information determined for the data at a backend server and thereby reduces the volume of data that need to be filtered at a frontend server. The multi-level privacy evaluation technology first applies an initial privacy check on a large data set at the backend to authoritatively filter out any data that a viewing user is not permitted to view or access and return as results a smaller data set that the viewing user may be permitted to view or access. A full privacy check is then performed at the frontend on the smaller data set, resulting in reduction in the overall cost of performing privacy checks and reducing latency in displaying data to the viewing user.

Growing community of inventors

Mountlake Terrace, WA, United States of America

Shiyu Zhao