Search Engine Comparisons By Thomie Ventura Search Engines
Search Engine Comparisons By: Thomie Ventura
Search Engines Today, much, but not all, of the work we do revolves around the web n Internet is accessible to almost anyone n Impact on businesses, schools, professionals, home users n Web is changing every day, but everything is still not ACCESSIBLE n
FTP Servers Only way of sharing files up to 1990 n FTP Servers and FTP Clients n Down Side n Servers were mostly known through word of mouth n Not everyone was setting up their servers n
Grandfather, Grandmother, Mother n Archie ( Grandfather) n n Veronica (Grandmother) n n Used FTP file Servers Used Gopher file Servers World Wide Web Wanderer (Mother) First Robot n Caused Controversy n n Are Robots a good or bad thing for the Internet?
“Web Search” n What exactly does it mean? Involve tools ? n Accessing proprietary databases such as www. Factiva. com or www. dialog. com n n We’ll focus on “web search” as an open web source, and look at a searchers point of view
Difficulty Coping n Volume and Speed of the web and Search Engines Something new happens each day n So many things to do, so little time to do it n n Dynamic nature of web searching (indexing new documents) n Staying up-to-date with traditional tools( also undergo changes) n Other random issues that arise everyday
Will an “open web” search engine always have my answers? n Questions that should arise about searching the web How long did it take to get it? n What is the database or search engine? n What kinds of questions will it help me answer? n n Open web will not always give me the answer n What can it be used for?
Quality of Information Anyone can become a publisher n Evaluating content is crucial n Reputation n Background n Qualifications n Where did it come from? n What its purpose? n Relevant to my topic? n
Limitations of General Web Search Tools n Spiders don’t crawl in real-time n n Recency Linked or Submitted Sites n If a website contains 1000 pages, does not mean Search Engines make all of them accessible
Invisible or Hidden Web resources n Examples: Interacting resources, return “custom” sites n Registration n n Why is it hidden? Created on the fly n Spiders don’t fill in registration forms n “No-Robot” Tag n
Hidden is not always bad Research and Effort n Without proper tools, we can make large databases even larger n Google n Altavista n Excite n n Distributing Information Properly
Specialized Focused and Site Specific Search Tools n Necessary and Important n Hidden Web is out of reach of general purpose Search Engines More Precision than Recall n Examples: n n www. Psychcrawler. com www. Inomics. com [http: //newssearch. bbc. co. uk/ ksenglish/query. htm],
![Identifying and Collecting Specialized Engines n Profusion n n [http: //www. profusion. com] Librarians](http://slidetodoc.com/presentation_image_h2/af33e098988c7fbfbeffb0ffffcdea01/image-13.jpg "Identifying and Collecting Specialized Engines n Profusion n n [http: //www. profusion. com] Librarians")
Identifying and Collecting Specialized Engines n Profusion n n [http: //www. profusion. com] Librarians Index Covers large amount of specialized and invisible web databases n [http: //www. lii. org] n
Meta – Search Engines n Major Disadvantages You get it all!! High Recall Low Precision n Basics of Search Engines used n Send queries to “pay for placement” engines n n A good metasearch Engine n www. vivisimo. com
Old Pages, GONE! n Trying to find old pages? n n Contact webmaster Fortunately Archiving Old Material n Example: n n [http: //www. clinton. nara. gov/index. html] n ALexa Research n n [http: //archive. alexa. com/] carries over 18 terabytes of data covering some 5 million Web sites and some 1. 9 billion pages
Search Engine Sizes n n This is a search engine size analysis as of December 11, 2001 Google Dominates
Sizes Over Time
Closer Look
Dealing with Coping n Use the Search Engine n Conduct research on a topic n This will get you familiar with search engine n You can see how results are displayed n Relevancy of returned documents n Let you gather your own bookmarks
Understanding limitations n What to do with these limitations? Know limitations n Use more than one search engine n Use “specialized” search engines that go deeper into a site to collect more information n Use “invisible web” resources n Use web directories, and bookmark important sites n
Ability to Search Multimedia n Now Available, but still expanding Wait weeks now becomes instant n search tools that provide access to video and audio material using a non-text mechanism to access the material ex: searching a specific background or type color n Still image tools n n Google, Altavista, and Fast, use text surrounding image
Become Aware of Multimedia Search n Video Searches n n n Virage www. virage. com TVeyes www. tveyes. com Shadow. Tv www. shadowtv. com Wordwave www. wordwave. com Speech. Bot (keyword search engine demo by Compaq, uses speech technology to create real-time transcripts) www. speechbot. com Image Searches n n Webseek (search or browse criteria in image) www. ctr. columbia. edu/webseek/ Visoo( uses software that looks for words embedded in image www. visoo. com
Making Old Pages Stay n Long Term? n n Offer comments ( suggest how material can be more accessible and searcheable, a great archive of content without the correct means of accessing it will be a hassle and is not great) Short Term? n n Take advanatage of Googles cache feature ( google crawls a site and makes a copy unless unauthorized, and puts it on server, if site is gone, the copy is in googles server, you must go to search results and next to URL go to “cached”, will not always be there, next time spider crawls site and it is missing it will not save onto server www. savethis. com (lets you save web pages, and access them)
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