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Boolean Operators

Boolean operators (AND, OR, NOT) serve to either narrow or expand your search:

OR expands it by including synonyms or related terms:

  • For example: (veterans or military or soldiers or service*)
  • For example: ("higher education" or college or university or "post secondary" or postsecondary)
  • For example: (ptsd or "post traumatic stress disorder" or "posttraumatic stress disorder" or "post-traumatic stress disorder")

AND narrows it by finding the subset of articles that contain both search terms you want:

  • homeless* AND veteran*
  • eye-tracking and memory and recall
  • "eye movement measurements" and "information literacy" and attention

NOT narrows your search by eliminating articles that contain a specific term you do not want:

  • eye-tracking and memory and recall and (child* or adult*) NOT (seniors or elderly)

An easy way to remember the difference is the rhyme OR gives you MORE, while the other two operators give you less (although there may be better results).

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