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Fast, Inclusive Searches for Geographic Names Using Digraphs

March 14, 2008

An algorithm specifies how to quickly identify names that approximately match any specified name when searching a list or database of geographic names. Based on comparisons of the digraphs (ordered letter pairs) contained in geographic names, this algorithmic technique identifies approximately matching names by applying an artificial but useful measure of name similarity. A digraph index enables computer name searches that are carried out using this technique to be fast enough for deployment in a Web application. This technique, which is a member of the class of n-gram algorithms, is related to, but distinct from, the soundex, PHONIX, and metaphone phonetic algorithms. Despite this technique's tendency to return some counterintuitive approximate matches, it is an effective aid for fast, inclusive searches for geographic names when the exact name sought, or its correct spelling, is unknown.

Publication Year 2008
Title Fast, Inclusive Searches for Geographic Names Using Digraphs
DOI 10.3133/tm7A1
Authors David I. Donato
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Techniques and Methods
Series Number 7-A1
Index ID tm7A1
Record Source USGS Publications Warehouse
USGS Organization Eastern Geographic Science Center