Search engine indexing

About: Search engine indexing is a research topic. Over the lifetime, 20909 publications have been published within this topic receiving 516954 citations.

Placing search in context: the concept revisited.

Abstract: Keyword-based search engines are in widespread use today as a popular means for Web-based information retrieval Although such systems seem deceptively simple, a considerable amount of skill is required in order to satisfy non-trivial information needs This paper presents a new conceptual paradigm for performing search in context, that largely automates the search process, providing even non-professional users with highly relevant results This paradigm is implemented in practice in the IntelliZap system, where search is initiated from a text query marked by the user in a document she views, and is guided by the text surrounding the marked query in that document (“the context”) The context-driven information retrieval process involves semantic keyword extraction and clustering to automatically generate new, augmented queries The latter are submitted to a host of general and domain-specific search engines Search results are then semantically reranked, using context Experimental results testify that using context to guide search, effectively offers even inexperienced users an advanced search tool on the Web

Dimensionality reduction for fast similarity search in large time series databases

Abstract: The problem of similarity search in large time series databases has attracted much attention recently. It is a non-trivial problem because of the inherent high dimensionality of the data. The most promising solutions involve first performing dimensionality reduction on the data, and then indexing the reduced data with a spatial access method. Three major dimensionality reduction techniques have been proposed: Singular Value Decomposition (SVD), the Discrete Fourier transform (DFT), and more recently the Discrete Wavelet Transform (DWT). In this work we introduce a new dimensionality reduction technique which we call Piecewise Aggregate Approximation (PAA). We theoretically and empirically compare it to the other techniques and demonstrate its superiority. In addition to being competitive with or faster than the other methods, our approach has numerous other advantages. It is simple to understand and to implement, it allows more flexible distance measures, including weighted Euclidean queries, and the index can be built in linear time.

The X-tree: an index structure for high-dimensional data

Abstract: In this paper, we propose a new method for indexing large amounts of point and spatial data in high-dimensional space. An analysis shows that index structures such as the R*-tree are not adequate for indexing high-dimensional data sets. The major problem of R-tree-based index structures is the overlap of the bounding boxes in the directory, which increases with growing dimension. To avoid this problem, we introduce a new organization of the directory which uses a split algorithm minimizing overlap and additionally utilizes the concept of supernodes. The basic idea of overlap-minimizing split and supernodes is to keep the directory as hierarchical as possible, and at the same time to avoid splits in the directory that would result in high overlap. Our experiments show that for high-dimensional data, the X-tree outperforms the well-known R*-tree and the TV-tree by up to two orders of magnitude.

The R+-Tree: A Dynamic Index for Multi-Dimensional Objects

Abstract: The problem of indexing multidimensional objects is considered. First, a classification of existing methods is given along with a discussion of the major issues involved in multidimensional data indexing. Second, a variation to Guttman’s Rtrees (R+-trees) that avoids overlapping rectangles in intermediate nodes of the tree is introduced. Algorithms for searching, updating, initial packing and reorganization of the structure are discussed in detail. Finally, we provide analytical results indicating that R+-trees achieve up to 50% savings in disk accesses compared to an R-tree when searching files of thousands of rectangles.

Introduction to MPEG-7: Multimedia Content Description Interface

Abstract: From the Publisher: The MPEG standards are an evolving set of standards for video and audio compression. MPEG 7 technology covers the most recent developments in multimedia search and retreival, designed to standardise the description of multimedia content supporting a wide range of applications including DVD, CD and HDTV. Multimedia content description, search and retrieval is a rapidly expanding research area due to the increasing amount of audiovisual (AV) data available. The wealth of practical applications available and currently under development (for example, large scale multimedia search engines and AV broadcast servers) has lead to the development of processing tools to create the description of AV material or to support the identification or retrieval of AV documents. Written by experts in the field, this book has been designed as a unique tutorial in the new MPEG 7 standard covering content creation, content distribution and content consumption. At present there are no books documenting the available technologies in such a comprehensive way. Presents a comprehensive overview of the principles and concepts involved in the complete range of Audio Visual material indexing, metadata description, information retrieval and browsingDetails the major processing tools used for indexing and retrieval of images and video sequencesIndividual chapters, written by experts who have contributed to the development of MPEG 7, provide clear explanations of the underlying tools and technologies contributing to the standardDemostration software offering step-by-step guidance to the multi-media system components and eXperimentation model (XM) MPEG reference softwareCoincides with the release of the ISO standard in late 2001. A valuable reference resource for practising electronic and communications engineers designing and implementing MPEG 7 compliant systems, as well as for researchers and students working with multimedia database technology.