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 An “information retrieval system”  searches the computer system to find the required information.

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Presentation on theme: " An “information retrieval system”  searches the computer system to find the required information."— Presentation transcript:

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2  An “information retrieval system”  searches the computer system to find the required information.

3  The most public, visible form of a search engine  İnformation it searches for can be: › Web pages › İmages › Other types of files

4  The very first tool leading the web search engines: Archie › Collects the file names and creates an unindexed database from the collection. › Created by a student of McGill University,Montreal › The name stands for “archive” without “v”

5  The first search engine: Wandex. › Created by an MIT student.  One of the first full-text crawler-based search engines: WebCrawler *crawler: something that crawls like a reptile  Another popular search engine: Lycos, first started in Carnegie Mellon.  Then came other search engines: Excite,Altavista,Infoseek…

6 Yahoo provides directory browsing

7  How did Google become the most popular among others? An innovation called “Page Rank” Minimalist interface rather than embedding a web search engine into a web portal

8 I. Web Crawling II. Indexing III. Searching Web Crawling: an automated web browser follows every link it sees. Indexing: words are extracted from titles, headings,meta tags * meta tag:

9 Search Target 1: Odysseuss2009.org  Best rating percentage: Yahoo.com  Least #of results: Excite.com  Worst rating percentage: Windows Live / MSN Search ( search.msn.com ) (0%) * Excite.com is actually a meta search engine and shows results from other search engines.

10  Best rating percentage among meta engines: Dogpile.com  Worst rating percentage: Apollo7.co.uk (almost 0%) * The engines that the meta search engines collect results from, change from one meta search engine to another. Therefore their performances change accordingly.

11 Search query: “Loss of customer goodwill in lot-sizing”, an article by Deniz Aksen * all results including links to the article, or the pages where article is cited/referred are accepted as “hit”. Best rating percentage: Ask.com (found 1 st in almost all searches) Worst rating percentage: Lycos.com (almost none of the results are hit) Best rating percentage among meta engines: Mamma.com

12 Worst rating percentage among meta engines: Donbusca.com * Samples are to show only results of some searches,there are a total of 480 searches with various keywords for one target search result. The remaining are included in excel sheets in detail.


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