Often you will use the Boolean connectors AND, OR or NOT to describe your request. For example:
. . . would retrieve every article which contained the words "clinton" and "dole" in the same article. Of course some of the stories might be about a "Dole pineapple" packing plant in "Clinton County" but chances are most of the stories will mention Bill Clinton and Bob Dole.
clinton and dole
The OR connector is used when you want articles containing either one term or another. This may happen with synonyms. For example:
Remember, an AND search tends to reduce the number of hits, while an OR search tends to increase them.
doctor or physician
The NOT connector is rarely used -- and in fact should be always be employed cautiously since you can accidentally "not out" stories you did not intend to exclude. For example, suppose you had a local businessman whose name happened to be "Michael Jordan." When searching for him you would naturally want to exclude stories on the more famous basketball-playing Michael Jordan. In that situation you might consider using the NOT connector for the following search:
However, doing so may inadvertantly exclude a wonderful, extensive feature story on the businessman Michael Jordan, in which the story says, "Centerville's Michael Jordan may not play basketball very well, but he sure knows how to . . ."
Michael Jordan not basketball
Perhaps a better search statement would be:
This is a wiser use of the NOT connector since a feature story on the businessman Michael Jordan might mention "basketball," but would not likely appear in the Sports section.
michael jordan not section(sports)
It is a good rule of thumb to use parentheses whenever you are writing a search
Often you will need to use both AND and OR connectors in a single search statement. For example, you may want to know about lawsuits against doctors. Both of the concepts "doctors" and "lawsuits" have more than one potential term. So you might use a search like:
Notice that the synonymous OR terms are "nested" within parentheses. This tells the library search engine that you wish to resolve the "nested" queries first and then combine them with the exterior connections.
(doctors or physicians) and
(lawsuits or suits or malpractice)
For example, suppose you want to know about pet food products. The stories you want may be about "dogs" or "cats" or just "pets" but they will certainly be about "food." So a reasonable search statement might be:
You may think it is obvious that you are interested in "dog food" or "cat food" or "pet food." And indeed, most search engines do resolve OR combinations before AND combinations, but you should always remember that computers are notoriously stupid beasts, and it would not be unusual for a comptuer to interpret the above search as a request for every story about dogs along with every story about cats along with any stories specifically about pets and food.
dogs or cats or pets and food
So, whenever you combine AND and OR connectors, put in parentheses the portion of the search you wish to be resolved first. The above search would be best written as:
It is a good rule of thumb to use parentheses whenever you are combining both AND and OR searches.
(dogs or cats or pets) and food
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