Abstract: The disclosed embodiments provide a system for processing data. During operation, the system stores a set of feed updates associated with a set of entities in descending chronological order within a set of resizable blocks. For each entity in the set of entities, the system generates an index containing one or more lists of resizable blocks storing a subset of the feed updates associated with the entity, wherein the one or more lists are sorted in descending chronological order. The system then uses the index to generate a content feed containing a selection of the feed updates for outputting to a viewer.

Abstract: A system and methods are provided for forecasting the volume of future events that match specified attributes regarding type of event (e.g., serving of an advertisement impression, a page view, fraudulent activity), attributes of entities involved in the events (e.g., users, content items, system components), and/or other factors. A forecast query is received with one or more terms identifying target criteria of a campaign (e.g., an ad campaign, some other content-serving campaign). The query is decomposed into a first set of terms corresponding to attributes for which one or more predefined models exist, and a second set of terms for which no models exist. The predefined model for the first set of terms (or for a third term that is a superset of the first set of terms) is then used to estimate a number of future events that match the query terms.