Title
Document Retrieval on Repetitive String Collections.
Abstract
Most of the fastest-growing string collections today are repetitive, that is, most of the constituent documents are similar to many others. As these collections keep growing, a key approach to handling them is to exploit their repetitiveness, which can reduce their space usage by orders of magnitude. We study the problem of indexing repetitive string collections in order to perform efficient document retrieval operations on them. Document retrieval problems are routinely solved by search engines on large natural language collections, but the techniques are less developed on generic string collections. The case of repetitive string collections is even less understood, and there are very few existing solutions. We develop two novel ideas, interleaved LCPs and precomputed document lists, that yield highly compressed indexes solving the problem of document listing (find all the documents where a string appears), top-k document retrieval (find the k documents where a string appears most often), and document counting (count the number of documents where a string appears). We also show that a classical data structure supporting the latter query becomes highly compressible on repetitive data. Finally, we show how the tools we developed can be combined to solve ranked conjunctive and disjunctive multi-term queries under the simple $${\\textsf{tf}}{\\textsf{-}}{\\textsf{idf}}$$tf-idf model of relevance. We thoroughly evaluate the resulting techniques in various real-life repetitiveness scenarios, and recommend the best choices for each case.
Year
DOI
Venue
2017
10.1007/s10791-017-9297-7
Information Retrieval
Keywords
DocType
Volume
Document retrieval on strings,Repetitive string collections,Suffix trees and arrays
Journal
20
Issue
ISSN
Citations 
3
1386-4564
3
PageRank 
References 
Authors
0.46
41
7
Name
Order
Citations
PageRank
Travis Gagie164363.61
Aleksi Hartikainen2371.98
Kalle Karhu3243.56
Juha Kärkkäinen4135495.20
Gonzalo Navarro510911.07
Simon J. Puglisi6113275.14
Jouni Sirén722214.85