Scope

• Combining sets of the results of previous searches enables you to increase the precision of your search.

Requirements and Limitations

• You can use Boolean operators to combine two or more sets of results by using the R# numbers to the left of the set of results of a previous search.
• You can also use nesting with parentheses ( ).
• You can only do this in the Advanced Search mode, not in Keyword or Relevance modes.
• You can not combine the sets through the use of proximity operators.

Example Search

• A patron wants to know about how "public health" issues in general related to anthrax or smallpox or terrorism.
• In Expanded Academic ASAP, a subject (use the pulldown menu) search on anthrax or smallpox (all three words in the same line) gives me the first set:
  • R1 (su (anthrax or smallpox))
  • View 3156 Citations; Modify Search
• A subject search on terrorism give me the second set:
  • R2 (su terrorism)
  • View 30177 Citations; Modify Search
• A keyword search on the phrase "public health" give me the third set:
  • R3 ("Public health")
  • View 18352 Citations; Modify Search
• Use the pulldown menus to combine the sets as follows: r3 and (r2 or r1) to get the fourth set:
  • R4 (rn (R3 and (R2 or r1)))
  • View 275 Citations; Modify Search