Meta Platforms, Inc.
Policy compliance verification using semantic distance and nearest neighbor search of labeled content

Abstract:

An online system determines whether a test content item violates a policy of the online system. The online system extracts a semantic from the test content item and determines a distance between the extracted semantic vector and the stored semantic vectors for content items that have been labeled to indicate whether they violate a policy. Using a nearest neighbor search, the online system selects a set of the stored semantic vectors and assigns a weight to the selected semantic vectors that is inversely related to the distances. The online system then determines whether the test content item violates a policy using a weighed voting scheme, where the labels of the stored semantic vectors are aggregated based on their associated weights. The online system may first attempt to match the test content with known bad content and terminate the more complex nearest neighbor search if such a match is found.