Indri at TREC 2006: Lessons Learned From Three Terabyte Tracks

This report describes the lessons learned using the Indri search system during the 2004-2006 TREC Terabyte Tracks. We provide an overview of Indri, and, for the ad hoc and named page nding tasks, discuss our general approach to the problem, what worked, what did not work, and what could possibly work in the future.