XM-Tree, a new index for web information retrieval
Keywords:Metric spaces, Similarity Searching, M-Tree, XM-Tree
Web Information Retrieval is another problem of searching elements of a set that are closest to a given query under a certain similarity criterion. It is of interest to take advantage of metric spaces in order to solve a search in an effective and efficient way. In this article, we present an extension of the M-Tree index, called XM-Tree, in order to improve search results. This index allows dynamic insertion of new data, reduces search costs using pruning and precalculated distances, and uses a tolerable amount of space, which makes this index apt for the extensive and dynamic Web. The proposed extension indexes Web documents, uses L2 as indexing distance and L∞ as similarity criterion to solve queries. We also present experiments validating the results.
 R. Baeza-Yates y B. Ribeiro-Neto. (eds.). Modern Information Retrieval. ACM Press, New York, 1999.
 P. Ciaccia, M. Patella y P. Zezula. “M-Tree: An Efficient Access Method for Similarity Search in Metric Spaces”, Proc. of the 23rd Conference on Very Large Databases (VLDB’97), 1997; pp. 426–435.
 C. Traina Jr., A. Traina, B. Seeger y C. Faloutsos. “Slim-trees: High Performance Metric Trees Minimizing Overlap between Nodes”, Proc. of 7th International Conference on Extending Database Technology, LNCS, 1777, 2000; pp. 51–68.
 X. Zhou, G. Wang, J. Xu Yu y G. Yu. “M+-tree: A New Dynamical Multidimensional Index for Metric Spaces”, Proc. of the 14th Australasian Database Conference, 2003; pp 161 – 168.
 X. Zhou, G. Wang, X. Zhou y G. Yu. “BM+-tree: A Hyperplane-based Index Method for High-Dimensional Metric Spaces”, Proc. of 10th International Conference Database Systems for Advanced Applications, LNCS, 3453, 2005; pp 398–409.
 M. R. Vieira, C. Traina Jr., F. J. T. Chino y A. J. M. Traina. “DBM-Tree: Trading Height-Balancing for Performance in Metric Access Methods”, Journal of the Brazilian Computer Society, v. 11, n. 3, 2006; pp 20.
 A. Ocsa y E. Cuadros-Vargas. “DBM*-Tree: An Efficient Metric Acces Method”, Proc. of ACM Southeast Regional Conference, 2007; pp 401–406.
 P. Ciaccia y M. Patella. “The M2-tree: Processing Complex Multi-Feature Queries with just one Index”, Proceedings of DELOS Workshop: Information Seeking, Searching and Querying in Digital Libraries, 2000.
 S. Brin y L. Page. “The Anatomy of a Large-Scale Hypertextual Web Search Engine”, Proc of the Seventh International World Wide Web Conference, vol. 30 of Computer Networks and ISDN Systems, 1998, pp. 107–117.
 D. J. Delorie. DJGPP. Copyright (c) 2003 URL http://www.delorie.com/djgpp/