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Databases & Search Engines Wildcards,Truncation, Nesting

Databases & Search Engines Wildcards,Truncation, Nesting. IS530 Dr. Dania Bilal Fall 2009. Searching IRs. Most IRs provide searching capabilities using wildcards & truncation IRs includes Dialog and similar databases, Web search engines and OPACs Purpose

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Databases & Search Engines Wildcards,Truncation, Nesting

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  1. Databases & Search EnginesWildcards,Truncation, Nesting IS530 Dr. Dania Bilal Fall 2009

  2. Searching IRs • Most IRs provide searching capabilities using wildcards & truncation • IRs includes Dialog and similar databases, Web search engines and OPACs • Purpose • Increase number of retrieved results by broadening a specific search

  3. Searching IRsNesting • Most IRs allow use of nesting techniques. • Purposes: • Retrieve more precise search results • Avoid retrieval of “false drops” or “false hits” • Boolean operators are executed based on their strengths: • NOT Strongest, processed first • AND Stronger, processed second • OR Strong, processed last • Appropriate use of nesting with Boolean forces retrieval software to process searches with specific operators inside a ‘nest’ or ‘parentheses’ first, then combine the results of the sets.

  4. Nesting • Search technique used to group similar terms or terms that have relationships together to increase search results • Synonyms and related terms are usually used to broaden a search using the OR operator inside a nest containing two or more terms • Nested terms are then combined with the AND operator

  5. Nested Searches: Examples (information seeking OR search strategies) AND (Internet OR world wide web) Class Exercise 1. Try the search above in Google and give the total no. of records retrieved.

  6. Nested Searches: Examples (“information seeking” OR “search strategies”) AND (Internet OR “world wide web”) Class Exercise 2. Try the search above in Google and give the total no. of records retrieved.

  7. Nested Searches: Examples (information seeking OR search strategies) AND (Internet OR world wide web) Class Exercise 3. Try the search above in Yahoo and give the total no. of records retrieved.

  8. Nested Searches: Examples (“information seeking” OR “search strategies”) AND (Internet OR “world wide web”) Class Exercise 4. Try the search above in Yahoo and give the total no. of records retrieved.

  9. Nesting in EBSCO HOST (information seeking OR search strategies) AND (internet OR world wide web) Without selecting any field or an operator for the search boxes will retrieve: 1,035 results Caution: If you misspell a word, no correction in spelling is made.

  10. Nesting in Dialog *File 1: The file has been reprocessed. Dialog accession numbers have changed. Set Items Description --- ----- ----------- ? ss (information seeking or search strategies) and (internet or world wide web) S1 2698 INFORMATION SEEKING (ADDED 08/13/1968) S2 3323 SEARCH STRATEGIES (ADDED 08/13/1968) S3 16573 INTERNET (ADDED 02/23/1996) S4 6077 WORLD WIDE WEB (ADDED 06/26/1996) S5 963 (INFORMATION SEEKING OR SEARCH STRATEGIES) AND (INTERNET OR WORLD WIDE WEB)

  11. DialogSearching without Nesting ? ss information seeking or search strategies and internet or world wide web S6 2698 INFORMATION SEEKING (ADDED 08/13/1968) S7 3323 SEARCH STRATEGIES (ADDED 08/13/1968) S8 16573 INTERNET (ADDED 02/23/1996) S9 6077 WORLD WIDE WEB (ADDED 06/26/1996) S10 8768 INFORMATION SEEKING OR SEARCH STRATEGIES AND INTERNET OR WORLD WIDE WEB

  12. DialogNesting and Proximity • The most precise search to formulate on this topic in Dialog is: ? ss (information(w)seeking or search(w)strategies) and (internet or world(w)wide(w)web) S11 215883 INFORMATION S12 12289 SEEKING S13 2970 INFORMATION(W)SEEKING S14 18817 SEARCH S15 111104 STRATEGIES S16 3558 SEARCH(W)STRATEGIES S17 16573 INTERNET (ADDED 02/23/1996) S18 57657 WORLD S19 26836 WIDE S20 17244 WEB S21 7174 WORLD(W)WIDE(W)WEB S22 1023 (INFORMATION(W)SEEKING OR SEARCH(W)STRATEGIES) AND (INTERNET OR WORLD(W)WIDE(W)WEB) Results:1,023 with the proximity (w) 8768 without the proximity (w) (previous slide)

  13. EBSCO Wildcards Two symbols are employed: • A question mark ? • A pound sign # • The ? Wildcard symbol • Enter your search terms and replace a single unknown character with the ? • Example: • ne?t • Will findcitations containing neat, nest or next. (net will not be retrieved because the wildcard replaces a single character).  

  14. EBSCO Wildcards • The # wildcard symbol • Used in places where an alternate spelling may contain an extra character. • Example: colo#r • Will retrieve all citations containing color or colour.

  15. EBSCO Truncation • Truncation is represented by an asterisk (*). To use truncation, enter the root of a search term and replace the ending with an *. • Example: comput* will retrieve records with the words computer, computing, computation, computational. • The Truncation symbol (*) may also be used between words to match any word (exactly as used in Google). • Example: a midsummer * dream will return results that contain the exact phrase, a midsummer night’s dream.

  16. Wildcard in Dialog ? s wom?nS26 43937 WOM?N ? s womanS27 3759 WOMAN ? s womenS28 42413 WOMEN (ADDED 07/01/1966)

  17. Truncation in Dialog ? s beef?S29 203 BEEF? ? s beefS30 185 BEEF

  18. Dialog Logoff Hold ? logoff hold Just enter a command to reestablish your session (this is the message you get in Dialog when you logoff hold) Keeps your search for 30 minutes Once you logon again and type DS, you will see the results of the previous search.

  19. Truncation in Google • Google use the * for truncation Example 1: search strateg* Results 1 - 10 of about 2,330,000 for search strateg* Example 2: search strategy Results 1 - 10 of about 107,000,000 for searchstrategy

  20. More about YahooShortcuts for Quick Searching For a definition: Type define followed by a word • Example: define “web 2.0” For weather: Type weather followed by the location • Example: weather knoxville For maps: Type map followed by the location • Example: map knoxville For Yellow Pages: Type a five-digit zip code

  21. Class Exercises Go to Yahoo • Type your zip code. What did youfind? • Type map and your location. What did you find? • Type weather casablanca. What did you find? • Type define“information science” Define:“information science”also works. What did you find?

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