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LIR 10: Week 8. Advanced Searching Techniques and Subject-Specific Databases. Boolean Review. AND narrows your search results to the “intersection” of your terms OR retrieves the largest amount of search results; any and all terms included will be retrieved
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LIR 10: Week 8 Advanced Searching Techniques and Subject-Specific Databases
Boolean Review • AND narrows your search results to the “intersection” of your terms • OR retrieves the largest amount of search results; any and all terms included will be retrieved • NOT narrows your search by excluding the search term specified • Using Boolean operators affects the precision and recall of your search results.
Word order is not important in statements when using OR or AND Word order is very important when constructing a search statement using NOT For example: theater NOT improvisational … will retrieve articles containing the word theater that do not include the term improvisational. Improvisational NOT theater … will retrieve articles containing the word improvisational that do not include the term theater. Boolean Review
Parenthetical Grouping Adjacency or Proximity Operators Truncation Limit Options Phrase Searching Advanced Searching Techniques
Advanced Boolean Searching:Parenthetical Grouping Boolean operators may be combined to reflect complex search statements: (teaching OR instruction) AND aviation • This statement instructs the search engine to find every record that has the words “aviation” and either “teaching” or “instruction” in the database. • Note that the separate parts of the search have been enclosed in parentheses, or grouped. This is done in order to keep the terms being controlled by the operator OR together in a set. • It also forces the order of processing: the search engine will first look for records that include the terms “teaching” or “instruction.” It will then look within that group and find records that also contain the word “aviation.”
Parenthetical Grouping, cont. • A search statement may have more than one parenthetical grouping. The example below combines two search concepts: French and theater, but takes into account many synonyms that might be found for each concept: (French OR France) AND (theater OR drama OR performance)
Adjacency Operators: Adjacency or Proximity operators can also be used to assist with constructing a search statement. These are not true Boolean Operators, but “behave” similarly. Adjacency operators dictate how search terms should be positioned. They are: NEAR WITH (or WITHIN) ADJ The most frequently used of the adjacency operators is NEAR. For example, if looking for articles about technological obsolescence, a search statement using an adjacency operator might be: technological NEAR obsolescence AND 8-track Adjacency Operators
Proximity or Adjacency Operators, cont. • The WITHIN command will instruct the search engine to find articles where the first word appears some number of words before or after the second word. • Some databases reduce adjacency commands to a “shorthand” code. For example, ProQuest shortens WITHIN to “W”: computer W/3 careers … will search for the term “computer” within three words of the term “careers”
Truncation • Truncating a search term refers to the addition of a symbol at the end of a word so the search engine will look for all variations of the word. • Truncation symbols vary by database. Most databases use either a question mark (?) or an asterisk (*) to denote truncation. For example: famil? AND poverty will instruct the database to find articles with the term “poverty” AND either the words "family" or "families" • Always check the “Help” section of the database you’re searching to see which truncation symbol is used.
Truncation, cont. • Use truncation when you want to find both the singular and plural forms of a word or words that begin with the same root : … will search technological OR technology near obsolescence OR obsolescent technolog* NEAR obsolescen* AND 8-track
Truncation, cont. • Be careful not to truncate word roots that have many variations. • For example, in a search for information about cats: cat* … will search for cat, cats, catastrophe, catechism, catamaran, catch, ad nauseum. • In this case, it would be better to combine “cat” with “cats” using parenthetical grouping: (cat OR cats OR feline*) AND feral
Wildcards • Wildcards let you substitute symbols for one or more letters when you’re searching words that might be spelled different ways, have the same root, or if you’re not sure of the spelling of a word. • For example, ProQuest databases use a question mark for wildcard searches: wom?n …will search for woman OR women • Always check the Help section of the database you’re searching to learn how wildcards are used. Every database is different! ProQuest and Infotrac vary greatly in their use of wildcards and proximity commands.
Limit Options • Limiting your search can help you increase the precision of your results • Standard limit options include date range, documents with full text and scholarly (vs. popular) journals. • Most limit options appear as radio buttons, boxes or drop down menus on the search (or advanced search) page.
Phrase searching • Phrase searching instructs the search engine to find words together, in a precise order. • Searching a group of words as a phrase is perhaps the most useful way to increase the precision of your results. • Quotation marks are the most common way to designate a phrase. They are used in subscription databases and Internet search engines. • For example: “enemy combatants” “restless legs syndrome” “sudden oak death” “weight loss” AND (cortisol OR hydrocortisone)
Search Example Using ProQuest “weight loss” AND (cortisol OR hydrocortisone) • Use ProQuest advance search: • Search for “weight loss” in article text AND (cortisol OR hydrocortisone) in article text AND…?
Homework for Next Week • Boolean Operators Assignment
Subject Specific Databases • The SRJC libraries provide access to a wide range of subject specific databases • Browse through the list at: http://www.santarosa.edu/library/ftdb • The same search will provide completely different results, depending on the database you choose. • Every database will feature its own unique interface. Use the Help section to make sure you’re searching effectively.
Yet More Homework for Next Week • Online Periodicals Assignment 2
Exploring Specialized or Subject-Specific Databases • Open a browser (Netscape or Explorer) • From the Library’s home page, select Magazine Articles and Other Databases • Browse through the list of Database Subjects and select an appropriate choice for your topic. • Begin searching! Don’t forget to check “where you are” at the opening search screen and click on Help for useful search tips.