1. A method for identifying and ranking documents contained in a plurality of document collections that form a metacollection, comprising the steps of: receiving a query string at a metasearch engine, and transmitting terms in said query to search engines associated with said document collections; at each search engine, computing local statistics related to said terms for the documents in a collection with which said search engine is associated, and providing said local statistics to the metasearch engine; computing at least one global statistic related to the documents in the metacollection, in response to receipt of said local statistics at the metasearch engine, and transmitting said global statistic to said search engines; determining relevancy scores for said documents at said search engines in accordance with said global statistic; and providing references to documents in said metacollection in accordance said relevancy scores.