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PSYC 201 Resource Guide: Search Strategies

Practice Boolean Logic!

Combining search terms and variables using Boolean operators

Once you have identified the keywords and major concepts from your research statement that you want to find, you can build a database query using  Boolean logic, which uses the combining operators AND, OR, NOT between search terms to sort them for the most effective results.

For example, consider the following search statements using the same variables with AND, OR, NOT:

  • self-serving bias AND positivity bias
    (AND narrows and focuses the search to retrieve only the data relating to both "self-serving bias" and "positivity bias")

  • self-serving bias OR positivity bias
    (OR widens the search to retrieve everything about either "self-serving bias" or "positivity bias," whether or not there is a correlation between the variables)

  • self-serving bias NOT positivity bias
    (NOT excludes the variable "positivity bias" to only retrieve data about "self-serving bias" but not where the variable "positivity bias" occurs)


This video from the University of Auckland Libraries in Australia explains Boolean operators very well, and shows how they work in library catalogs, databases, and even Advanced Google.