databases & search engines wildcards,truncation, nesting

Databases & Search EnginesWildcards,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– Increase number of retrieved results by

broadening a specific search

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.

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

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.

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.

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.

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.

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.

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)

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

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 WEBS21 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)

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 find citations containing neat, nest or next. (net will not be retrieved because the wildcard replaces a single character).  

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.

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.

Wildcard in Dialog

? s wom?n

S26 43937 WOM?N ? s woman

S27 3759 WOMAN ? s women

S28 42413 WOMEN (ADDED 07/01/1966)

Truncation in Dialog

? s beef?

S29 203 BEEF?

? s beef

S30 185 BEEF

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.

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 search strategy

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

Class Exercises

Go to Yahoo1. Type your zip code. What did you find?2. Type map and your location. What did you

find?3. Type weather casablanca. What did you find?4. Type define “information science”

Define: “information science” also works. What did you find?