M0 3 : Access of Information

1. Identify Search Evaluate Use Present M03:Access of Information See also: Chapter 3 and Chapter 5, Riedling. Introduction to Information Literacy

2. Outline • Searching • Resources • Tools (for searching the Internet) • Search engines • Subject directories / web directories • Invisible web / deep web • Strategies • Techniques Introduction to Information Literacy

3. Identify Search Evaluate Use Present Review: The Steps in an Information Research Process • Identify • To identify the problem and the information needs. • Search • To develop a search strategy and to search the information you need. • Evaluate • To evaluate the information obtained. • Use • To extract, summarize and analyze the information to solve the problem. • Present • Write a paper and give a presentation. Do not forget to cite the information sources. Introduction to Information Literacy

4. How do I Get the Information I Need? Introduction to Information Literacy

5. Resources:Where to search for information? • Printed materials • books, journals, magazines, newspapers, library catalogs, etc. • Non-printed materials and the Internet • Videos, audios, verbal (talking to people), periodical databases (including online databases), and the Internet Our focus Note: Some materials are available in both printed and electronic format. Introduction to Information Literacy

6. Tools:Searching the Internet • The Internet contains a lot of information, but it is not indexed like the library’s catalog. • Searching the Internet requires part skill, part luck, and a little bit of art. Introduction to Information Literacy

7. The Various Search Tools on the Internet • Search engines • Uses a computer program (called web-spider) to navigate through the web and collect information about web pages. • Subject directories / web directories • Manual entry and classification • Invisible web / deep web • Includes dynamic electronic databases that are not searchable through search engines. Introduction to Information Literacy

8. Tool #1: Search Engines • They maintain a large index for a huge number of Internet sites by retrieving each individual web pages. • Google claims to have indexed 8,058,044,651 web pages, as of 22nd June 2005. • Examples: • Google: http://www.google.com • AltaVista: http://www.altavista.com • Yahoo!: http://www.yahoo.com Note: Sometimes it is better to use a special-purpose search engine. E.g. Would you use Google to query about a KMB bus route? Introduction to Information Literacy

9. Can search engines find everything on the Internet? • No. Search engines cannot index the pages in the invisible web / deep web: • Pages which are not linked to by other pages. • Dynamic Web pages based on responses to database queries. • Sites that require registration or otherwise limit access to their pages. More on dynamic web pages later in this module. Introduction to Information Literacy

10. Page Ranking Policies • Important question: How do search engines rank their search results? • Relevancy to the search keywords • Importance of the pages (e.g. More links to the page from important sites indicates importance.) Exception Some search engines put advertisers' pages at the top, called paid placement, sponsored links or sponsored listing. Introduction to Information Literacy

11. Special Topic:Meta-Search Engines • They search other search engines, then combine and organize the results from those searches. Thus, they do not maintain indexes of web pages. • Examples: • Profusion: http://www.profusion.com • Metacrawler:http://www.metacrawler.com • Info.com: http://www.info.com Introduction to Information Literacy

12. Meta-Search Engines:A Potential Problem • Usually too much information is found instead of not enough. • The usefulness of meta-search depends on how good the combining and organizing functions are. • E.g. How well does the meta-search engine eliminate duplicated results? Introduction to Information Literacy

13. Special Topic: Newsgroups • Newsgroups are discussion forums available through Internet services providers, as well as at Lingnan University. • Each group is usually dedicated to a certain discussion topic. The topic is usually reflected by a unique name. e.g. • talk.politics.european-union • lingnan.hostelc • Access through a news reader software. E.g. • Mozilla / Netscape / Thunderbird • Microsoft Outlook Introduction to Information Literacy

14. Searching the Newsgroups • The newsgroups contain the following kinds of information that may be difficult to find elsewhere: • Personal opinion and other informal information • Very specific but unpopular topics (e.g. the solution to a rare bug in Microsoft Word, which may not have been formally documented) • Very current topics about which web sites are not yet available • Use Google Groups to search through various newsgroups: http://groups.google.com • When reading a post in a newsgroup, please pay special attention to the date of a post and the group in which the post belongs. These help you evaluate the usefulness of the post. (We will learn more about information evaluation in M05.) Introduction to Information Literacy

15. Problems Related to Newsgroups • Virtually any one can view and post in a newsgroup. This leads to the following problems: • Many spam (junk) posts (e.g. advertisements) • Privacy: others may capture email addresses from the posts • Many uninformative or inaccurate posts ?! Introduction to Information Literacy

16. Tool #2: Subject Directories • Also called web directories • A directory on the World Wide Web that specializes in linking to other web sites and categorizing those links • All linked pages are classified and reviewed by human • Examples • Yahoo: http://www.yahoo.com • Google: http://directory.google.com • Open Directory Project: http://www.dmoz.org Introduction to Information Literacy

17. Subject Directories vs. Search Engines • Many people do not make enough use of the subject directories. Instead, they go directly to search engines. • Keep in mind that subject directories often contain carefully chosen lists of quality Internet sites. They are sometimes more useful than a search engine. Introduction to Information Literacy

18. Tool #3: Invisible Web / Deep Web • There is a huge amount of information that is stored in databases accessible on the Web, but not available via search engines. • It is likely to contain very current, dynamically changing information, including news, job listings, airline flights, etc. • E.g. Online electronic databases at the Lingnan University library Introduction to Information Literacy

19. Strategies:Think before you search! The general strategies of a search: • Pre-search analysis • Executing the search • Looking for an overview • Seeking expert advice Introduction to Information Literacy

20. Pre-search Analysis • Identify any societies, organizations that have the information you sought at their websites • E.g. To get a list of Government Departments in Hong Kong, it is faster use visit the Hong Kong Government’s official website, instead of using a search engine. • Identify any distinctive words, phrases, acronyms associated with the topic. • Identify other words that are likely to appear in any web pages over the topic. • Identify any synonyms, variations in spelling for the previously identified words or phrases, e.g. using OR. Introduction to Information Literacy

21. Pre-search Analysis (Cont’d) • Identify any irrelevant documents that these search words/phrases may pick up. • Identify other words/phrases to describe the broader subject area that may be useful when searching a subject directory • Prepare the search terms according to the techniques discussed in Boolean Search Introduction to Information Literacy

22. Executing the Search • Use your search terms in a search engine • Use Boolean operators to increase or decrease the number of matches, as described previously. Introduction to Information Literacy

23. Looking for an Overview • Search in a subject directory using the broader subject term • Search in a subject directory using your narrower keywords • Links from the subject category should point you to the main sites about the subject • Lookup the subject matter in an encyclopedia (e.g. Wikipedia) Introduction to Information Literacy

24. Seek Expert Advice • Seek advice from relevant mailing lists, newsgroups, or other discussion groups. • Sometimes you come across experts in those forums who can point you to difficult to find articles or resources. • Search Google Groups if you think the topic may have been previously discussed in newsgroups. Introduction to Information Literacy

25. Techniques:How to get better search results? • Phrase search • Boolean operators • AND, OR, NOT • Stop words • Wildcards Introduction to Information Literacy

26. Phrase Search • Example: • You want to find information about a person called Lee Sai Man. With double quotation marks: Google gives: “lee sai man” Lee Sai Man, Ng Sze Kun, Julia, 000009452XXX,… (This is called Phrase search.) Google gives the result above, plus the following: However, without the double quotation marks: LAW Pui Man. A. LEE Kam Fung. A. LEESai Po. lee sai man Introduction to Information Literacy

27. Boolean Search salt sugar salt sugar Salt OR sugar Salt AND sugar Each search engine may use different syntax and rules for OR, NOT, AND. You should check up the help pages for your favorite search engines. In many search engines, AND is implicit by default. salt sugar Salt AND NOT sugar Introduction to Information Literacy

28. Boolean Search Examples • OR search example: • museum (london OR paris) • NOT search example: • "comparative literature" NOT "department of" • Google uses - to indicate NOT • in Google: "comparative literature" –"department of" • Reference: Google Help Center Introduction to Information Literacy

29. To Get Fewer Matches… • Using more AND terms can also narrow the search or reduce the number of matches, e.g.: • "president bush" AND "iraq war" AND WMD AND claims Introduction to Information Literacy

30. To Get Fewer Matches… • Using NOT can further eliminate groups of matches, e.g.: • "comparative literature" NOT "department of" • sars NOT "south african revenue service" NOT "south africa" Introduction to Information Literacy

31. To Get More Matches… • Using more OR terms will increase the number of matches, e.g.:- • profitability airline gives 265,000 matches in Google, while profitability airline OR airlines gives 685,000 matches. • Use a broader term: • E.g. Use operating system instead of windows Introduction to Information Literacy

32. Stop Words and Wildcards • Search engines stop words: • common words such as the, in, 3, etc. • are ignored by most search engines as search keywords • Some search engines support wildcards: book* will match books, bookstore, bookworms, etc. Introduction to Information Literacy