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Term-ordered query evaluation versus document-ordered query evaluation for large document databases

Marcin Kaszkiel, Justin Zobel
1998 Proceedings of the 21st annual international ACM SIGIR conference on Research and development in information retrieval - SIGIR '98  
There are two main families of technique for eficient processing of ranked queries on large text collections: document-ordered processing and term-ordered processing.  ...  We show that they have similar costs for short queries, but that for long queries document-ordered processing is much more costly.  ...  There are two principal techniques for evaluation of ranked queries: term-ordered (TO) processing and document-ordered (DO) processing.  ... 
doi:10.1145/290941.291031 dblp:conf/sigir/KaszkielZ98 fatcat:qwsbnmhtojezbdd32wiwjvbs7q

Performance Evaluation of MongoDB and PostgreSQL for Spatio-temporal Data

Antonios Makris, Konstantinos Tserpes, Giannis Spiliopoulos, Dimosthenis Anagnostopoulos
2019 Zenodo  
Specifically, PostgreSQL is four times faster in terms of response time in most cases and presents an average speedup around 2 in first query, 4 in second query and 4,2 in third query in a five node cluster  ...  The evaluation is based upon real, business scenarios and their subsequent queries as well as their underlying infrastructures, and concludes in confirming the superiority of PostgreSQL.  ...  ACKNOWLEDGMENTS The research work was supported by the Hellenic Foundation for Research and Innovation (HFRI) and the General Secretariat for Research and Technology (GSRT), under the HFRI PhD Fellowship  ... 
doi:10.5281/zenodo.2649876 fatcat:cp5bjvswdvbzdnxczhoakt26zy

Collection selection for managed distributed document databases

Daryl D'Souza, James A. Thom, Justin Zobel
2004 Information Processing & Management  
In a distributed document database system, a query is processed by passing it to a set of individual collections and collating the responses.  ...  In this paper, we re-evaluate several techniques for collection selection.  ...  Consider Figure 1 , which presents a set of ranked documents generated from querying an n-term index. The similarities are query-document similarity scores and are ordered from highest to lowest.  ... 
doi:10.1016/s0306-4573(03)00008-6 fatcat:ygdpyr7r7rfs5is7vdr4otoq6e

Mitos: Design and Evaluation of a DBMS-Based Web Search Engine

Panagiotis Papadakos, Yannis Theoharis, Yannis Marketakis, Nikos Armenatzoglou, Yannis Tzitzikas
2008 2008 Panhellenic Conference on Informatics  
Two of these representations are one order of magnitude more space efficient and two orders of magnitude faster in query evaluation, than the plain relational representation.  ...  A rather unusual design choice is that its index is based on an object-relational database system.  ...  Specifically we will study the trade-off, between the index size (and query evaluation times) and the ability of the index to support multiple access paths, e.g. by term versus by document.  ... 
doi:10.1109/pci.2008.46 dblp:conf/pci/PapadakosTMAT08 fatcat:6uurygdapzg3ddb4kp6j7neplq

Efficient XML Data Management: An Analysis [chapter]

Ullas Nambiar, Zoé Lacroix, Stéphane Bressan, Mong Li Lee, Ying Guang Li
2002 Lecture Notes in Computer Science  
and document-centric aspects of XML query processing.  ...  We present efficiency results for two native XMLMS, an XML-enabled semi-structured data management system and an XML-enabled RDBMS, which emphasize the need for a delicate balance between the data-centric  ...  We thank the XENA project team for providing us with the source code and valuable comments in setting up XENA.  ... 
doi:10.1007/3-540-45705-4_10 fatcat:gl4v4lwuqzb5verinxnyabbp5y

A system for the retrieval of Italian broadcast news

Marcello Federico
2000 Speech Communication  
Query-document matching is based on a statistical term weighting scheme. The system was tested on a 203 story collection of audio news, augmented with 9,500 newspaper articles.  ...  The evaluation was based on a "known item" retrieval task and aimed at evaluating the impact of speech recognition errors and query expansion on retrieval performance.  ...  Thanks are also given to Mauro Cettolo, Edmondo Trentin, and Rachel Weatherhead for revising this manuscript.  ... 
doi:10.1016/s0167-6393(00)00022-4 fatcat:pkgtrstclvadjppipakvne7ulq

TopX: efficient and versatile top-k query processing for semistructured data

Martin Theobald, Holger Bast, Debapriyo Majumdar, Ralf Schenkel, Gerhard Weikum
2007 The VLDB journal  
query processing for semistructured data, (3) support for integrating thesauri and ontologies with statistically quantified relationships among concepts, leveraged for word-sense disambiguation and query  ...  It efficiently supports vague search on both content-and structure-oriented query conditions for dynamic query relaxation with controllable influence on the result ranking.  ...  queries [21] evaluated on traditional database indexes.  ... 
doi:10.1007/s00778-007-0072-z fatcat:pwqyugrna5cypncgn52jofsnem

Page 58 of Library & Information Science Abstracts Vol. , Issue 7 [page]

1995 Library & Information Science Abstracts  
Evaluation criteria include ease of use versus complexity and cost considerations, in terms of precision and recall.  ...  branch-and-bound and dynamic query ordering.  ... 

Efficient and effective metasearch for a large number of text databases

Clement Yu, Weiyi Meng, King-Lup Liu, Wensheng Wu, Naphtali Rishe
1999 Proceedings of the eighth international conference on Information and knowledge management - CIKM '99  
Each user query is evaluated against the set of representatives of all databases in order to determine the appropriate databases to search.  ...  When the number of databases is very large, say in the order of tens of thousands or more, then a traditional metasearch engine may become inefficient as each query needs to be evaluated against too many  ...  Garcia-Molina for providing us with the collection of documents and queries used in our experiments.  ... 
doi:10.1145/319950.320005 dblp:conf/cikm/YuMLWR99 fatcat:jmhxi3fh3nd2rcz3jgt5qmjxmm

Effectiveness of Keyword-Based Display and Selection of Retrieval Results for Interactive Searches [chapter]

Ezio Berenci, Claudio Carpineto, Vittorio Giannini, Stefano Mizzaro
1999 Lecture Notes in Computer Science  
that contain a specified subset of query terms.  ...  In particular, we found that the VIEWER users retrieved half as many nonrelevant documents as the AltaVista users while retrieving a comparable number of relevant documents.  ...  Acknowledgments We would like to thank Giovanni Romano for his help in preparing the first experiment and evaluating its results.  ... 
doi:10.1007/3-540-48155-9_9 fatcat:hn3wmg6oq5hklkyokhb36d2p3y

Effectiveness of keyword-based display and selection of retrieval results for interactive searches

Ezio Berenci, Claudio Carpineto, Vittorio Giannini, Stefano Mizzaro
2000 International Journal on Digital Libraries  
that contain a specified subset of query terms.  ...  In particular, we found that the VIEWER users retrieved half as many nonrelevant documents as the AltaVista users while retrieving a comparable number of relevant documents.  ...  Acknowledgments We would like to thank Giovanni Romano for his help in preparing the first experiment and evaluating its results.  ... 
doi:10.1007/s007990000035 fatcat:ka2axtpqjvdefpxd222jofe4om

Effective reformulation of Boolean queries with concept lattices [chapter]

Claudio Carpineto, Giovanni Romano
1998 Lecture Notes in Computer Science  
When REFINER i s presented with a Boolean query, it builds and displays a portion of the concept lattice associated with the documents being searched centered around the user query.  ...  The results of an experiment conducted on a medium-sized bibliographic database showed that the performance of REFINER was better than unrefined Boolean retrieval.  ...  Acknowledgments We thank three anonymous reviewers for pointing out relevant work in the field of cooperative databases and for many useful comments and suggestions.  ... 
doi:10.1007/bfb0055993 fatcat:g6ehpj3bind7po3vbxcgvyaxwm

Comparing the performance of database selection algorithms

James C. French, Allison L. Powell, Jamie Callan, Charles L. Viles, Travis Emmitt, Kevin J. Prey, Yun Mou
1999 Proceedings of the 22nd annual international ACM SIGIR conference on Research and development in information retrieval - SIGIR '99  
However for a given level of recall, search e ort appears to scale linearly with the number of databases.  ...  Their performance is compared using a common testbed designed specifically for database selection techniques. The testbed is a decomposition of the TREC TIPSTER data into 236 subcollections.  ...  We thank Margaret Connell for her assistance with experiments reported here.  ... 
doi:10.1145/312624.312684 dblp:conf/sigir/FrenchPCVEPM99 fatcat:zuuo7k63kbdv5l5tjgdpxk4wri

Large Scale Deep Convolutional Neural Network Features Search with Lucene [article]

Claudio Gennaro
2016 arXiv   pre-print
We evaluated different strategies of textual representation in order to optimize the index occupation and the query response time.  ...  In order to show that our approach is able to handle large datasets, we have developed a web-based prototype that provides an interface for combined textual and visual searching into a dataset of about  ...  However, if database is large, this approach can become time-consuming.  ... 
arXiv:1603.09687v4 fatcat:az7f3irxmzd3bhhxvp7bdzxhq4

A New Subject-based Document Retrieval from Digital Libraries Using Vector Space Model

Sayed Mahmood Bakhshayesh, Azadeh Mohebi, Abbas Ahmadi, Amir Badamchi
2018 Proceedings of the 2018 Federated Conference on Computer Science and Information Systems  
We define this score by introducing a new vector space model in which a vectorized subject-based representation is defined for each document and its keywords, and the terms in the query, as well.  ...  Document retrieval from digital libraries based on user's query is highly affected by the terms appeared in the query.  ...  For this purpose, the query is processed first in order to extract its distinguished terms, i.e. q 1 , q 2 , . . . , q r .  ... 
doi:10.15439/2018f260 dblp:conf/fedcsis/BakhshayeshMAB18 fatcat:sarsgetwj5ek3jbgx2n7kkyihu
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