Archive for June, 2010

Indexes vs. Full-Text Searching

Sunday, June 20th, 2010

Researchers who rely entirely on full-text searching, i.e. searching the Web using a search engine such as Google, are missing information.  Indexes improve searching not only in terms of accuracy and thoroughness, but also speed, according to Mary Elizabeth Williams in the article “Dr. Searchlove: Or how I learned to stop Googling and love pre-coordinate indexing.”

The article reports the results of a Bureau of National Affairs usability study, in which law students completed a series of single answer and more complex research tasks using the online version of United States Law Week.  They answered half the questions using text searches.  For the other half they used the online index.

Williams reports that using the index was, in the case of both types of research tasks, faster and more successful than text searching.  Overall, index users had an 86 percent success rate while text searchers had only a 23 percent success rate.  Disregarding all unsuccessful searchers, most of whom were text searchers, successful index users took about 57 seconds per search and successful text searchers took about 2 minutes and 47 seconds per search.  In addition, index users made bonus discoveries by pursuing cross references and browsing through headings and/or subheadings.

Williams states that free text as a research tool decontextualizes information.  Researchers are likely to miss unique concepts common to the field of legal research, as well as comparisons to related terms that might be useful.  They will often miss the outer limits of a research task since results in free text searching seemingly have no boundaries.


Williams, Mary Elizabeth. (Sept/Oct 2005) “Dr. Searchlove: Or how I learned to stop Googling and love pre-coordinate indexing.”  AALL Spectrum. Date of Access: June 20, 2010.

For more information about the services provided by the author of this blog, see the Stellar Searches LLC website,