When using the Boolean operator NOT,
you DO NOT allow the computer to locate documents that contain the
word typed after it. In other words, it ignores all the pages that
contain the word you type after the operator NOT. Think of it this
way: IF I want to find Web sites on all sports, but NOT on golf because
I don't like golf, THEN I will type this in the search box: sports
NOT golf. (It is best to capitalize Boolean operators because some
search engines require it.)
sports NOT golf
is the same as typing
+sports -golf
(You need to put one space before and after
the word NOT. There's no space after
the + and - ,
but there is a space between the +sports and
the -golf.)
What about combining AND with NOT? Picture a yummy ice cream sundae.
You like bananas and fudge on your ice cream sundae, but you're allergic
to nuts.
banana AND fudge NOT nut
* Notice
the singular form of the keywords were used. Usually, it is best
not to search for the
plural of a word. If you want information on scooters, and type the
plural form (scooters) in the search box, you will miss all those
pages that have scooter (the singular form) on them.
Turn on Rockwell
Schrock's Boolean Machine to better understand
the concept of using NOT. Roll your cursor over AND, OR, and NOT
and watch what happens to the picture.
Let's try this search with NC
WiseOwl. Quick tip: Print these directions
before you link to the site.
(If you are asked for a password, type: wiseowl.)
- Click ENCYCLOPEDIAS on the NC
WiseOwl home page.
- Click the OPEN button underneath Grolier Multimedia Encyclopedia.
- Find the search box, and then click on the button labeled ADVANCED.
You're going to do an advanced search using Boolean logic!
- Make sure FULL TEXT
SEARCH is selected.
You want to search through entire articles, not the "article
titles only."
- Let's imagine that you want to study all types of precipitation except rain. You would use a statement that looks like this:
precipitation NOT rain
- Type precipitation in the first large search box.
- Select NOT from the little drop menu, instead of AND.
- Type rain in the search box to the right of NOT.
- Click GO.
- How
many "hits" did
you get? _____
- Do a search again, but this time only type rain in the search
box and click GO! (Don't make any other changes like you did earlier.)
- How many "hits" did
you get? More than
before, right?!
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