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Lecture Database system concepts - Chapter 19: Information retrieval

This chapter covers decision support, including online analytical processing and data mining and information retrieval. In this chapter introduce data analysis and mining with the following contents: Relevance ranking using terms; relevance using hyperlinks; synonyms, homonyms, and ontologies; indexing of documents; measuring retrieval effectiveness; web search engines; information retrieval and structured data; directories. | Chapter 19: Information Retrieval Database System Concepts ©Silberschatz, Korth and Sudarshan See www.db­book.com for conditions on re­use Chapter 19: Information Retrieval s Relevance Ranking Using Terms s Relevance Using Hyperlinks s Synonyms., Homonyms, and Ontologies s Indexing of Documents s Measuring Retrieval Effectiveness s Web Search Engines s Information Retrieval and Structured Data s Directories Database System Concepts ­ 5th Edition, Sep 2, 2005 19. ©Silberschatz, Korth and Sudarshan Information Retrieval Systems s Information retrieval (IR) systems use a simpler data model than database systems q Information organized as a collection of documents q Documents are unstructured, no schema s Information retrieval locates relevant documents, on the basis of user input such as keywords or example documents q e.g., find documents containing the words “database systems” s Can be used even on textual descriptions provided with non­textual data such as images s Web search engines are the most familiar example of IR systems Database System Concepts ­ 5th Edition, Sep 2, 2005 19. ©Silberschatz, Korth and Sudarshan Information Retrieval Systems (Cont.) s .