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4774 Uppsatser om Media queries - Sida 1 av 319

Lost in translation? En empirisk undersökning av användningen av tesaurer vid queryexpansion inom Cross Language Information Retrieval

The purpose of this thesis is to examine the performance of queries that is expanded before translation in comparison with only translation of the queries using a bilingual dictionary, and also to see if the number of terms that was used to expand the queries was of any importance i. e. if many terms from a thesaurus helped or destroyed a query. To answer these questions i used two online thesauri, Rogets thesaurus and Merriam-Webster Online and one printed bilingual dictionary, Norstedts English-Swedish dictionary. Even though the number of examined queries is too small to draw any definite conclusions, the results suggest that expanding using a general thesaurus may have a negative effect on the queries.

Cross-language information retrieval : sökfrågestruktur & sökfrågeexpansion

This Master?s thesis examines different retrieval strategies used in cross-language information retrieval (CLIR). The aim was to investigate if there were any differences between baseline queries and translated queries in retrieval effectiveness; how the retrieval effectiveness was affected by query structuring and if the results differed between different languages. The languages used in this study were Swedish, English and Finnish. 30 topics from the TrecUta collection were translated into Swedish and Finnish.

Typer av sökfrågor på webben: En effektivitetsstudie

The purpose of this thesis is to examine the performance of different types of queries in the AltaVista query-based search engine. Thirty information needs have been collected from an ask-a-question service on the World Wide Web, which means that they are based on real users information needs. This is done to avoid partiality in the study. The author has invented different types of queries for each and every one of the information needs in accordance with the search syntax available for AltaVista. The types used are Boolean expressions, queries including proximity operators, phrases and queries directed towards a specific field.

Queryexpansion med böjningsvarianter och uppbrytning av sammansättningar

The purpose of this thesis is to examine the performance of queries that are expanded by 1 inflections, 2 compound splitting and 3 inflections and compound splitting combined. For compound splitting, the morphological analyser SWETWOL was used. Queries were executed in the Query Performance Analyser, QPA, containing the InQuery system. Query terms were selected from 29 topics, all of whom containing at least one compound word. Both the queries and the documents were in Swedish.

Den är ju liksom tuggad någon annanstans: Barnbibliotekariers upplevelser av barns och ungdomars ålagda frågor under referensintervjun

The purpose of my Masters thesis is to investigate how childrens librarians in public libraries perceive and meet imposed queries during the reference interview with children and young people. What do childrens librarians think about imposed queries from children and young people? What problems can arise during a reference interview with children and young people, and what strategies can be used to solve them? How can childrens librarians prepare for imposed queries from children and young people that have arisen in school related situations? The study was carried out at public libraries in Sweden. In the review of the literature results from prior research and other relevant material are presented. The theoretical framework includes a communication model on imposed queries developed by Gross, and two other models Levels of Mediation and Zone of Intervention, developed by Kuhlthau.

Query expansion med hjälp av en elektronisk tesaurus i en bibliografisk online-databas.

In this Masters thesis we investigate query expansion using an electronic thesaurus. We formed 30 topics from the library and information science field. For each topic three searches were made in the bibliographic database LISA Library and Information Science Abstracts via CSA Cambridge Scientific Abstracts. LISA has an electronic thesaurus attached. We used this thesaurus to form baseline queries, baseline queries expanded with synonyms, and baseline queries expanded with both synonyms and related terms.

Expansion av sökfrågor med Svenskt OrdNät som termkälla

The purpose of this Masters thesis is to examine the performance of queries that are expanded by synonyms and hyponyms from Svenskt OrdNät, the Swedish version of the Princeton WordNet. Four different types of queries were constructed: a baseline query S1, the baseline query expanded with synonyms S2, the baseline query expanded with hyponyms S3 and finally the baseline query expanded with the synonyms and hyponyms used in S2 and S3. The terms for expansion were picked by hand. The queries were executed in the Query Performance Analyser QPA, a tool used in IR education and in experimental IR research for analysing and comparing the performance of individual queries. 20 topics from the test collection GP_HDINF were chosen for the experiment.

Google Scholar eller Scirus för vetenskapligt material på webben? En utvärdering och jämförelse av återvinningseffektivitet.

This thesis evaluates and compares the retrieval effectiveness of the two search engines Google Scholar and Scirus, which both specialises in indexing scholarly material on the web as well as journal articles. Thirty search queries are used and the first twenty retrieved documents for each query are examined for topical relevance and scholarly content. The search queries are based on legitimate information needs taken from a scientific questionbox on the web. Queries are expressed with advanced search operators and are the same for both search engines. Precise relevance criteria are set up and a binary scale is used when judging.

A targeted evaluation of OpenEye?s methods for virtual ligand screens and docking

The process of drug discovery is very slow and expensive. There is a need for reliable in silico methods; however the performance of these methods differs.This work presents a targeted study on how the drug discovery methods used in OpenEye?s tools ROCS, EON and FRED perform on targets with small ligands. It was examined if 12 compounds (markers) somewhat similar to AMP could be detected by ROCS in a random data set comprised of 1000 compounds. It was also examined if EON could find any electrostatic similarities between the queries and the markers.

Hur sökfraser är utformade

Millions of people are using search engines every day when they are trying to find information on the Internet. The purpose of this report is to find out how people formulate search queries. The result in this report is based on an empirical study which is based on a search log from the Swedish search engine Seek.se.One of the results in this thesis is that nearly all search queries are based on keywords..

Ämnessökningar med kontrollerad vokabulär och naturligt språk: en jämförande studie med felanalys.

The aim of this thesis is to compare the effectivity of using a natural language and a controlled vocabulary when performing subject searches in the bibliographic database LISA Library and Information Science Abstracts. 20 topics were created and for each topic two searches were made, one by using a query formulated with natural language directed to the abstract field and the other one by using a query formulated with descriptors from the thesaurus in LISA directed to the descriptor field. The average relative recall amounted to 64,8% for the AB-queries and 54% for the DE-queries. Failure analysis showed that the majority of the relevant documents not retrieved by AB-queries could have been retrieved with other query terms, such as synonyms. In a natural language there are many different ways of expressing a topic, and this tends to have a negative effect on retrieval effectivity.

Sociala Medier : Interagera, engagera och komplettera

Social media has made it possible to have a conversation in real time through audio, images and text, with anyone worldwide. The easy availability of social media has created a new society. Companies and organizations have the opportunity to interact with their audiences and their target in a way not previously possible. Welcome to the Web 2.0 world!Social media is a collective name for the communication channels that allow users to communicate directly with each other in real time through text, image or sound. Examples of social media are blogs, SMS, Skype, Facebook, Flickr, Youtube, Linkedin and Myspace.The purpose of this essay is to explore social media's role and opportunities in terms of being able to influence companies and organizations marketing communication. We have used a qualitative approach and our thesis is based on a qualitative text analysis study where we have analyzed 13 articles (the articles are from scholarly journals, magazines and trade/professional) from 2007 to 2009.

"Din sökning gav tyvärr inga träffar" : en kvalitativ enkätstudie om användares svårigheter med att söka noter i Statens musikbiblioteks onlinekatalog

The purpose of this Master?s thesis is to study how well the online catalogue of The Music Library of Sweden works when ordinary users are searching for sheet music. The issues studied are: Why do the users fail to find the sheet music they are looking for? Do the users take advantage of the possibilities that the classification codes of the SAB system offer? If not, why?The source material of the study is 144 comments from a user questionnaire about the online catalogue and, in addition, the search log for one day (513 queries). The comments were sorted into seven groups depending on the type of information need, for example searches for certain instrumentation or genres and problems with spelling.

En studie av evalueringar av webbaserade söktjänsters återvinningseffektivitet

The aim of this thesis is to describe and critically investigate eight different evaluations of the retrieval effectiveness of webbased search engines. The questions to be answered in this investigation are: - What kind of relevance judgements have been used? - Which criteria have been used when judging the relevance of a document? - Which measures have been used? - How many queries have been used? - How were the queries constructed? - What document cut-off value has been used? - Has hypothes testing been applied? - What kind of webbased search engines have been included in the evaluations? The study showed that although the evaluations investigate the same phenomena, they are very different from each other in certain aspects. Generally the study showed that precision is the preferred measure in comparison to recall in the chosen evaluation even though all the included evaluations have constructed unique formulas for calculating precision. Some attempts to measure relative recall have been performed but they all suffer from different defects.

Effekten av avståndsoperatorer samt expansion med synonymer med avseende på återvinningseffektiviteten

This thesis examines the effects of proximity operators and query expansion with synonyms on retrieval performance. The queries were expanded with synonyms and structured with proximity operators where the permitted distance between terms varied from 1 to 3. The expansion terms were selected from the online lexical reference system WordNet. Initial query terms were selected from 28 topics that contained compound words and were chosen on the basis of their expandibility. The English morphological analyser ENGTWOL was used for normalization of query terms.

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