Undergraduate Library Orientation

What Are Keywords?

• Words that occur in a text more often than we would expect to occur by chance alone.
• These are terms used to retrieve documents in an information system such as a catalog or a search engine.
• When we merge these, we get a good definition of keywords:
  • Keywords are words that occur often in documents that meet a specific research need, and by searching for these terms, we get needed information.

Preparing to Use Keywords

• Searching for information is not always easy. Google may guess what we mean, but databases don’t. We get better results if we plan a bit before we search either with a search engine or a database.
• Using keywords instead of natural language (just typing our entire question in) improves search outcomes. Which means your research takes less time.

Searching

• One of the most creative aspects of research is the search process. Searching is a process of discovery that expands your knowledge and broadens your views. 
• Knowing how to focus your search can reduce what you find to a more manageable amount. On the other hand, your search might uncover no information at all. If so, you have to be persistent – possibly trying different approaches to find what you need.

Where to Start

• Identify keywords or concepts
• Most topics consist of two or more concepts. Developing effective search strategies depends upon identifying: 
  • the primary concept 
  • the secondary concepts 
  • the relationships between the concepts 
  • the keywords, synonyms, and related terms for each concept 

Use keyword searching to:

• start your research
• find specific information (a fact, date or name)
• find every occurrence of the words you enter in that search engine contents or database
• Remember computers don’t speak language so they can’t know what you mean so they find every match.

Do Search Engines or Databases Search Every Word in the Search String?
NO.  

• Each tool has a list of very frequent words that are not indexed.
• These are known as stop words and include words such as the definite and indefinite articles “the,” “a,” and “an.”

Keywords
So what are they exactly?

• They are terms that identify exactly what it is you are looking for.
• These often come from your research topic. 
• They are also words that are related to your main words such as synonyms or even antonyms.
• Having a number of terms which you are and are not looking for helps find more information which may be useful for your topic.

Pro Tips

• We all want to type in complete sentences, but computers don’t “speak” human language.
• Much of what we type in is just noise, meaning words that appear in everything written in English, like what, which, that, etc. 
• We are told that Google and other search engines ignore this “noise,” but that’s not exactly true. The noise will make it more problematic for search engines and databases to pinpoint what you want.
• Leave out the noise. Only enter the very few terms that describe what you need.
• For example, if you want to find the coldest temperature ever recorded in Antarctica, you should only search
  • coldest temperature in Antarctica.
  • Ever and recorded don’t help identify what you are looking for. Those words are just noise to the search tool.

More Pro Tips

• A related term to Antarctica is South Pole.
• When you search South Pole, many search tools search these two words separately, retrieving any item with the word South in it and any item with the Pole in it. Most of these items will have nothing to do with your question.
• Some search tools automatically “and” terms together that are entered together. This retrieves everything with the words south and pole in them but not necessarily with them right next to each other. So again, you will get hits that aren’t relevant to your search.
• To retrieve items with South and pole right next to each other, you often need to put “ “ around the terms. 
• “South Pole”

Boolean Searching

• One of the most effective ways to limit a search is to apply the principles of Boolean logic.
• Boolean searching depends on three logical operators:  AND, OR, NOT
• The effect of Boolean searching is often visualized with Venn diagrams.
• Using Boolean searching to link your search terms will improve your search capabilities.
• You can narrow your search using “and” or “not.”
• You can broaden your search by using “or.”
• These terms replace all that “noise” we humans like to use in our searches.
• Venn diagrams visualize Boolean searching.

Venn Diagrams

• A Venn diagram (also known as a set diagram or logic diagram) is a diagram that shows all possible logical relations between a finite collection of different sets. 
• They are used to teach elementary set theory and illustrate simple set relationships in probability, logic, statistics, linguistics, and computer science.
• They are a good way to visualize your search.

“OR”—When and Why?

Use “OR” to provide alternate search terms if a key term is likely to appear in more than one way – 

• Different spellings
• Capitalization or diacritics
• Abbreviation or acronym 

Examples:  

• British spellings such as “colour” for “color”
• Flambé and flambe refer to the same French cooking technique
• USA and United States of America refer to the same country

Examples:

• “OR” can be used to list related terms or alternate names or phrases   
• “OR” is a way of searching for more than one concept, either of which is relevant to your search.

Specific Examples

• lung OR pulmonary
• encryption OR code
• diabetes OR insulin
• Burma OR Myanmar

How Does “OR” Affect the Search?

• If you are searching for the terms A or B, a search with Boolean “or” will return all documents containing 
  • A
  • B
  • A and B together
• The area outside the circles contains terms or concepts not searched for.
• Note that “OR” has the effect of broadening a search.

Using Boolean "AND"

• The "AND" operator is used to combine elements of a multi-faceted topic in a single search string
• The effect of "AND" is to narrow a search by requiring that two or more search terms be present
• As with "OR," protocols vary -- and, AND, &, + -- as well as pull-down menus may be used by different search engines

How Does "AND" Affect the Search?

• In a search for concepts A and B, the relevant items are only those that have both A and B, indicated by the light yellow segment in the Venn diagram.
• AND results in a narrowing of search results.

Using Boolean "NOT"

• Occasionally, it is necessary to eliminate documents that are retrieved by the search terms but are irrelevant to the object of the search
• Homonyms and acronyms are typical examples of unwanted materials that may turn up in a search
• Example:  If you are looking for information on the care of pets, you may also retrieve the website for the dairy company PET

What Does "NOT" Do For a Search?

• In a search of the type A and not B, the Boolean operator retrieves items with A but filters out items containing A and B and only B.  The excluded items are shown in orange.
• "NOT" has the effect of narrowing a search.

Other Search Tools

• Truncation: chemi* 
  • Will retrieve chemist, chemistry, chemical, etc.
• Wild Card: colo*r 
  • Retrieves both color and colour. The * operates in the interior of a word instead of at the end of an input sequence

Be sure to read the information about search options available for the search engine you select. The conventions given here are illustrative, not universal.

Meta-Search Engines

• Meta-search engines simultaneously perform searches with multiple search engines. Because the protocols vary widely from one search engine to another, meta-search engines produce better results with simple keyword searches. 
• Questions to ask about meta-search engines: 
  • What databases does the search engine search? 
  • Is it possible to use truncation or wild cards? 
  • Is Boolean searching allowed? 
  • How are results ranked? 
  • Can you modify the results?