Coping with Growing Collections of Electronic Text

Despite the trend toward distributed information sources, future digital libraries may hold as much text in electronic form as current libraries do in print. Accessing such collections by content rather than by metadata will require search-engine technology to accommodate at least a hundred-fold growth in data size. Recent developments within the ACSys Cooperative Research Centre are described, including an e ective and cost-e ective retrieval system (PADRE) designed to scale to multi-terabyte levels, a very large test collection for use in retrieval evaluation, techniques for selecting information servers and combining their results and ideas for combining content searches with access by metadata. The authors wish to acknowledge that this work was carried out within the Cooperative Research Centre For Advanced Computational Systems established under the Australian Government's Cooperative Research Centre's Program.