Towards Efficient Positional Inverted Index

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21240%2F17%3A00307711" target="_blank" >RIV/68407700:21240/17:00307711 - isvavai.cz</a>

Result on the web

<a href="http://www.mdpi.com/1999-4893/10/1/30" target="_blank" >http://www.mdpi.com/1999-4893/10/1/30</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/a10010030" target="_blank" >10.3390/a10010030</a>

Result language

angličtina

Original language name

Towards Efficient Positional Inverted Index

Original language description

We address the problem of positional indexing in the natural language domain. The positional inverted index contains the information of the word positions. Thus, it is able to recover the original text file, which implies that it is not necessary to store the original file. Our Positional Inverted Self-Index (PISI) stores the word position gaps encoded by variable byte code. Inverted lists of single terms are combined into one inverted list that represents the backbone of the text file since it stores the sequence of the indexed words of the original file. The inverted list is synchronized with a presentation layer that stores separators, stop words, as well as variants of the indexed words. The Huffman coding is used to encode the presentation layer. The space complexity of the PISI inverted list is O((N-n)[log2bN]+([N-nα]+n)x([log2bn]+1)) where N is a number of stems, n is a number of unique stems, α is a step/period of the back pointers in the inverted list and b is the size of the word of computer memory given in bits. The space complexity of the presentation layer is O(-∑Ni=1[log2pn(i)i]-∑N'j=1[log2p'j]+N) with respect to pn(i)i as a probability of a stem variant at position i, p'j as the probability of separator or stop word at position j and N' as the number of separators and stop words

Czech name

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Czech description

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Type

J_SC - Article in a specialist periodical, which is included in the SCOPUS database

CEP classification

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OECD FORD branch

10201 - Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8)

Project

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Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2017

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Algorithms

ISSN

1999-4893

e-ISSN

1999-4893

Volume of the periodical

10

Issue of the periodical within the volume

1

Country of publishing house

CH - SWITZERLAND

Number of pages

14

Pages from-to

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UT code for WoS article

000398723600029

EID of the result in the Scopus database

2-s2.0-85018343597