CO1552 Web Application Development

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CO1552 Web Application Development

• Week 11

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Introduction

• The previous three weeks have been spent looking
  at the issues surrounding using multimedia on the
  Internet
• Today, we are going to finish off this semesters
  lectures by talking about
• Information
• Finding trustworthy information from the Internet
• Linked to LO1, Syllabus 1 (Different from Matrix)

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Finding Information

• Use a search engine
• Some search engines include,
• Alta Vista http//uk.altavista.com
• Ask Jeeves http//www.ask.co.uk
• Dogpile http//www.dogpile.co.uk
• Excite http//www.excite.co.uk
• Google http//www.google.co.uk
• HotBot http//www.hotbot.co.uk
• Infoseek http//infoseek.go.com
• Lycos http//www.lycos.co.uk
• Northern Light http//www.nlsearch.co.uk
• Yahoo http//www.yahoo.co.uk

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Finding Information

• Highly annoying when you search for things and
  receive pages and pages of links to sites that
  have nothing to do with what you were searching
  for
• You can make your searches more specific
• Making searches more specific will increase the
  likelihood that you find the information you are
  looking for

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Finding Information

• (The examples below use the search engine
  AltaVista)
• If you searched with the two words potato chips
  you would receive millions of pages that
  contained the words potato and chips or both
• You can use the and signs to narrow your
  search results

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Finding Information

• Attaching a to the start of a word will make
  the search engine ensure that that word is
  definitely found in the list
• Attaching a to the start of a word will make
  the search engine ensure that the word is
  definitely NOT found in the list
• E.g. searching for potato chips will ensure
  that a search engine only returns page that
  contain BOTH words (and not just one or the other)

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Finding Information

• The sign does not ensure that the two words are
  next to each other
• In order to ensure the words are next to each
  other, we can enclose the words in quotes to make
  them a phrase
• potato chips will bring back pages where the
  two words sit next to each other (and hence will
  have both words on the page)

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Finding Information

• Using a minus sign will ensure the word will be
  omitted (no pages will be found with those words)
• potato chips low fat
• Will NOT find low fat potato chips

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Finding Information

• We can also use wildcards in our search terms.
• We can attach an asterix to the end of a word,
  and it will match the beginning of a word
• E.g. searching for part will find particle,
  partition, partner etc.

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Finding Information

• Some search engines use boolean operators to
  narrow down searches
• These work in a similar way to the and

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Finding Information

• AND will find both words
• John AND Dempsey will find both John and Dempsey
  on a page
• OR will find one or the other, or both words
• John OR Dempsey will find John or Dempsey or John
  and Dempsey

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Finding Information

• NOT will ensure that the word is not found
• NOT Dempsey will return pages that do not
  contain Dempsey
• FOLLOWED BY will find pages where one word is
  followed by another word
• John Followed By Dempsey will find pages that
  have John Dempsey

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Finding Information

• NEAR finds pages where a word is no more than a
  specified number of words away from another word
• president NEAR Jackson would return pages where
  the word Jackson wasnt too far away from the
  word president
• Quotation marks () Words are treated as a
  phrase

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Finding Information

• How can we trust the information that we find?
• You can normally trust information found on
  academic websites
• .ac.uk
• .edu
• Use your own judegement

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Finding Information

• Bias!
• People find it difficult to write things without
  adding their own bias to their writings.
• If you were to find information on
  www.microsoft.com then it is likely to state they
  their products are super cool
• You should cross reference materials in order to
  make sure you dont become biased too

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Finding Information

• Cross-referencing this information can be quite
  difficult, and you have to use your own judgement
• If you found some information from Microsoft.com
  that said SQL Server ran at 10,000,000
  instructions per second, and then found
  information from Oracle.com stating SQL Server
  ran at 5,000,000 records per second, which one
  would you believe?
• It is always worth finding a third party to help
  your judgement

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Finding Information

• There are electronic academic journals
• A full list should be available from your library
• You may be a member of Athens (and if you are
  not you can easily become a member)
  http//www.athens.ac.uk
• Athens allows access to a huge collection of
  academic journals and books.

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Next week

• There are no more lectures until after Christmas
• Tutorials and practicals STILL RUN!!!