How does Nominex work?
The algorithms behind Nominex are based upon sound academic principles, relying heavily upon the phonetic rules described by Edward Carney (A Survey of English Spelling, 1994).
A specially written "workshop" program performs the various steps involved, this has been in development for more than two years.
An important part of the process is to translate each surname spelling into a phonetic version using the symbols of the IPA (international phonetic alphabet). Carney’s list of 225 spelling-to-pronunciation rules was used as the basis of these IPA versions, supplemented by additional rules created to deal with his numerous exceptions, as well as many other exceptions found in the corpus of British surnames.
The similarity scores created by Nominex rely upon comparing each surname with all other surnames in the database. This comparison can be performed on the fly in a live system in which case there will be a performance hit. Alternatively they can be pre-calculated, at the expense of some disk space. Those names whose scores fall in the top 20% or 25% may be regarded as variants that are close enough to be useful, while the lower ranking pairs would generally be discarded.
The steps involved are described in more detail on the next few pages.