Boolean Combinations and Search Limitations
Thomas Mann · 2005
Abstract Several techniques of searching can be used in multiple databases, and will enable you to be much more efficient in zeroing in quickly on the best sources. Among these techniques are Boolean combinations of terms, component word searching within controlled subject strings, word truncation, proximity searches, and limitations of sets by various specifications (language, date, geographic area code, document type). “Boolean” combinations derive their name from the British mathematician and logician George Boole (1815–1864); they refer to the capacities of most databases to combine multiple search elements within one inquiry. For example, a researcher interested in the topic “computer-assisted instructional techniques in the field of geography” was initially referred to the ERIC database, the largest index to journals and research reports in the field of education. This index has a list of controlled descriptor terms, somewhat analogous to the Library of Congress Subject Headings list used to standardize headings in book catalogs.