What are Boolean Operators Research Skills 8 Boolean

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What are Boolean Operators? Research Skills 8

What are Boolean Operators? Research Skills 8

¢ Boolean operators are named after George Boole, an Englishman, who invented them as

¢ Boolean operators are named after George Boole, an Englishman, who invented them as part of a system of logic in the mid-1800's. l The most common Boolean operators are AND, OR, NOT and NEAR, additionally, () and “ ”can be used. l They are used to combine search terms when doing research.

No… they aren’t leaning ghosts….

No… they aren’t leaning ghosts….

And ¢ Would everybody wearing Jeans, please stand up # _____ ¢ Would everybody

And ¢ Would everybody wearing Jeans, please stand up # _____ ¢ Would everybody wearing Sneakers please stand up # _____ ¢ Would everybody wearing jeans and sneakers please stand up # _____

Venn Diagram of AND Jeans Sneakers

Venn Diagram of AND Jeans Sneakers

AND Explained ¢ Using the operator AND between keywords will limit the results of

AND Explained ¢ Using the operator AND between keywords will limit the results of a search because all of the keywords have to be present in order for an item to be retrieved.

OR ¢ Would everybody wearing jeans please stand up #______ ¢ Would everybody wearing

OR ¢ Would everybody wearing jeans please stand up #______ ¢ Would everybody wearing sneakers please stand up #______ ¢ Would everybody wearing jeans OR sneakers please stand up #______

Venn Diagram of OR Jeans Sneakers

Venn Diagram of OR Jeans Sneakers

OR Explained Using the OR operator results in either or both of your search

OR Explained Using the OR operator results in either or both of your search terms appearing in your results. ¢ Using the OR operator will result in a larger number of retrieved items and therefore expands the search. ¢

NOT ¢ The NOT (or AND NOT) operator forbids the word after it from

NOT ¢ The NOT (or AND NOT) operator forbids the word after it from appearing in the items resulting from your search. ¢ Would everybody wearing Jeans but NOT sneakers, please stand up

Venn Diagram for NOT Jeans Sneakers

Venn Diagram for NOT Jeans Sneakers

NOT Explained Not helps to limit your search because it takes out a category

NOT Explained Not helps to limit your search because it takes out a category of undesirable results. ¢ NOT or AND NOT thus narrows or limits a search by excluding the keyword immediately following it. ¢

NEAR Finds the terms within 10 words of each other ¢ Domestic NEAR Violence

NEAR Finds the terms within 10 words of each other ¢ Domestic NEAR Violence ¢ l would make sure these two words appeared close enough to each other that they would be referring to domestic violence

( ) or “ ” ¢ Used to group together words or phrases, for

( ) or “ ” ¢ Used to group together words or phrases, for example (domestic NEAR violence) and (police AND trial) “domestic violence” “police trial”

Now lets try some on our own You should always use more than one

Now lets try some on our own You should always use more than one search engine when you are doing research ¢ Try thinking out of the box, give Google a break!! ¢ Other options: ¢ www. dogpile. com www. yahoo. com www. ixquick. com www. duckgo. com www. altavista. com www. ask. com www. excite. com