Organization: ACM
Category: IR Compress
Comment: テキストデータベースにあらわれる単語の出現位置を示すインデクス
        ファイル(concordance)の圧縮方法。小さな数は少ないビット数で
        表現するようにn-s符合化という、エリアス符合もどきを使っている。
        ・Dynamicなテキストデータに使えるような気がしない。
        ・もとのテキストは圧縮していないのが不思議。
Abstract: This paper describes a combination of compression
        methods which may be used to reduce the size of inverted
        indexes for very large text databases. These methods are
        Prefix Omission, Run-Length Encoding, and a novel family
        of numeric representations caled n-s coding.  Using
        these compression methods on two different text sources
        (the King James Version of Bible and a sample of Wall
        Street Journal Stories), the compressed index occupies
        less than 40% of the size of the original text, even
        when both stopwords and numbers are included in the
        index. The decreased time required for I/O can almost
        fully compensate for the time needed to uncompress the
        postings. This research is part of an effort to handle
        very large text databased on the CM-5, a massively
        parallel MIMD supercomputer.
Bibtype: InProceedings
Booktitle: Proceedings of the Sixteenth Annual International
        ACM SIGIR Conference on Research and Development in
        Information Retrieval
Month: jun
Pages: 88-95
Author: Gordon Linoff
        Craig Stanfil
Title: Compression of Indexes with Full Positional Information
        in Very Large Text Databases
Year: 1993
Super: SIGIR93
Publisher: ACM Press