Towards Efficient Positional Inverted Index

Kód výsledku v 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>

Výsledek na webu

<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>

Jazyk výsledku

angličtina

Název v původním jazyce

Towards Efficient Positional Inverted Index

Popis výsledku v původním jazyce

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

Název v anglickém jazyce

Towards Efficient Positional Inverted Index

Popis výsledku anglicky

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

Druh

J_SC - Článek v periodiku v databázi SCOPUS

CEP obor

—

OECD FORD obor

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

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2017

Kód důvěrnosti údajů

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

Název periodika

Algorithms

ISSN

1999-4893

e-ISSN

1999-4893

Svazek periodika

10

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

14

Strana od-do

—

Kód UT WoS článku

000398723600029

EID výsledku v databázi Scopus

2-s2.0-85018343597