AGGREGATION-SPECIFIC CONFIDENCE INTERVALS FOR FACT SET QUERIES

An aggregation operation is performed on a subset of facts sampled from a full structured collection of facts, to determine an aggregation result. Based on the determined aggregation result and on an indication of characteristics of the sampled subset of facts relative to the full structured collection of facts, an indication of a difference is determined, between what would be the result of the aggregation-type operation on the full structured collection of facts and the actual result of the aggregation-type operation on the sampled subset of facts. The full structured collection of facts may be comprised of a plurality of component structured collections of facts, where the sampled subset of facts includes facts that are sampled from the plurality of component structured collections of facts, in a manner that is deterministic across the component structured collections of facts, and then joined to constitute the sampled subset of facts.