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Graduate Research: Guide to the Literature Review

This guide is intended to introduce basic concepts related to preparing a literature review in the fields of information systems, information security, and computer science. Research requires time, patience, creativity, and problem-solving.

Introduction to Search Techniques

Searches of computerized resources are more effective if you know how to "talk to" the computer systems. Communicating with these systems requires knowing certain basic search techniques.

Because these techniques are so important for getting good search results, you should take the time to understand them -- and use them. They will vastly improve your search results in information services and when searching the Internet.

Whenever you begin to use a new computerized resource, look for "help" (or "search tips" or "instructions") that will tell you which of these search techniques is available in the resource and how to apply them in the specific resource you are using.

The search techniques introduced on this webpage are: Boolean operators, phrase searching, truncation/wildcards, and nesting.

Boolean Operators (Connector Words)

Connectors or operators are used to tell the computer how to combine the words you want to search. The Boolean operators "AND", "OR", and "NOT" are described below.  Note: Some research databases require that the Boolean operator be capitalized: AND, OR, NOT

AND

Use the connector "and" to tell the system that both terms are needed to describe the subject. That is, both terms must occur in the description of the article. For example, to search the topic "censorship of music" connect the keywords with "and" by typing:

censorship AND music

Both the word "censorship" and the word "music" will be in the items found.

Additional examples:

firearms AND legislation
divorce AND statistics AND dakota

OR

Use the connector "or" to tell the system that either one word or the other must appear in the description of the item. (This connector is used where alternative words may be used to describe the same subject). For example, if you type:

bones OR skeleton

Either the word "bones" or the word "skeleton" will be in the items found.

Additional examples:

mice OR mouse
farms OR ranches

NOT

Use the connector "not" to find items that have one word and do not have the other word. The second word cannot appear anywhere in the item. For example, to search for items about "aids" when you don't want the disease AIDS, type:

aids NOT disease

The items found will contain the word "aids" but not the word "disease."

Additional examples:

guns NOT hunting
albums NOT photograph

NOTE: To find out which of these techniques is available in web search engines, look for links such as Advanced Search, Search Options, or  Search Help  when searching Google, Bing, etc.. Search engines may require that you use specific symbols (e.g., plus or minus signs) instead of AND/OR/NOT, or they may require different methods for combining terms to accomplish ANDing and other search techniques.  

Phrase Searching

Most systems provide a method for you to search for a phrase - that is, to find two or more words side-by-side. This is an extremely important and powerful search technique for making sure that your search results are focused on your topic.

NOTE: Most library databases and web search engines now use quote marks. 

To search for two words side-by-side, place quotation marks around the phrase. For example, 

          "sex discrimination"

However, other search systems may require the use of some sort of connector word. Here are two different ways used to indicate phrases in two different search systems:

sex w discrimination
sex ADJ discrimination

In some systems, to search for the phrase "sex discrimination,"  just type:

sex discrimination               [NOTE: This is a system which automatically defaults to phrase searching. In such an research database or search engine, you will need to take some action to get it to combine words  -- AND, OR, NOT -- instead of treating the words entered as a phrase]

To know for sure what method is used in any given research database (or in a web search engine), you'll need to look for a "help" (or search options, or Advanced search) link in the research database or web search engine. 

Truncation / Wildcards

Save typing by using special symbols or "wild card" characters.

For example, instead of doing the search:

educator or educators or educational or education or educate

use the "root word" (the letters these words have in common) along with a "wildcard character" accepted by the search system. For example:

educat*

Truncation or wildcard characters are different in different systems, so be sure to use the correct wildcard character. For example, here are two different systems' ways of doing this search....

In Proquest: educat*
In Lexis-Nexis Academic Universe: educat!

Nesting

Nesting is the use of parenthesis to separate parts of your search phrase, thereby letting the computer know the order by which it is to conduct the search.          

         For example you want information on pest and weed control for tomatoes. You could perform two searches

               tomato AND pest and tomato AND weed

         By nesting, however, you can combine these searches into one. You need the term tomato and you also want the term pest or the term weed. By        combining the terms, your search query will look like this

               tomato AND (pest OR weed)

         The computer will first find all sources with the term pest or weed. Then it will limit those results to the items that also contain tomato. If you did not use  the parenthesis, a search for tomato AND pest OR weed may have brought back the results you wanted or it may have brought back the terms tomato and pest plus those that had weed without tomato.