Name games The author of the Iliad is either Homer or, if not Homer, somebody else of the same name.

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Name gamesThe author of the Iliad is either
Homer or, if not Homer, somebody else of the
same name. Aldous Huxley (1894 - 1963) Adrian
Esterman John Bass
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Name Comparison Techniques

• Exact matches are not sufficient - names can be
  misspelled for many different reasons
• Need special algorithms to see if two names are
  approximately the same.
• Phonetic coding algorithms
• Similarity indices

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Phonetic coding algorithms
Soundex Phonix NYSIIS Metaphone
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Soundex system (Russell, 1890)
1. Use the first letter of name 2. Drop a, e, i,
o, u, h, w and y 3. Create three digit code
according to Code    Letter       
1            b,f,p,v 2           
c,g,j,k,q,s,x, 3            d, 4           
l 5            m, n 6            r 4. A drop
letters having the same code 5. If necessary pad
with zeros
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Soundex system (Russell, 1890)
Examples Name Soundex code Adrian Esterman
A365 E236 Adrian Estermann A365 E236 Adrian
Easterman A365 E236
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Soundex system (Russell, 1890)

• Original soundex is flawed
• geared towards English names
• cant account for incorrect first letter
• longer names are truncated

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Phonix system (Gadd, 1990)
Soundex variant in which letters are mapped to a
set of codes using the same algorithm, but a
slightly different set of codes. Prior to
mapping about 160 letter-group transformations
are used to standardise the string. For example,
the sequence tjV (where V is any vowel) is
mapped to chV if it occurs at the start of a
string.
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New York State Identification and Intelligence
Algorithm (NYSIIS) (Taft, 1970)

• Builds a phonetic code of up to 6 letters for
  
• each name
• Much more complicated algorithm.
• Builds more precise phonetic codes
• Vowels are retained and all mapped to the
• letter A
• They found that NYSIIS is 98.7 accurate
• whereas Soundex is 96.0 accurate

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NYSIIS (Taft, 1970)
Examples Name NYSIIS Code Borthwick BART
WA Walker WALCAR Papadouka PAPADA
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Metaphone (Philips, 1990)
A similar code to Soundex, however
only consonants are retained and these are
reduced to consonants (not digits) B X S K J T
F H L M N P R 0 W Y where 0 represents the TH
sound
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Metaphone (Philips, 1990)
Examples Name Metaphone code Johnson JNSN Jen
sen JNSN Fitzwilliam FTSWLM
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Similarity Indices
Edit distance Jaro-Winkler
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Edit-Distance

• Edit distance operations
• Insertion, where an extra character is inserted
  into the string
• Deletion, where a character has been removed from
  the string
• Transposition, in which two characters are
  reversed in their sequence
• Substitution, which is an insertion followed by a
  deletion

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Edit distance

• Edit distance is measured as a count of edit
  distance operations from one string to another
• Strings with a small edit distance are likely to
  be similar
• Example
• internatianl to international has an edit
  distance of 2,
• i.e., 1 transposition 1 deletion

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Jaro-Winkler (1994)

• Developed at the U.S. Census and used in their
  post-enumeration survey
• Works as follows
• Input Name1, Name2
• Output Number between 0 and 1
• 1.0 Perfect match
• 0.5 Partial match
• 0.0 Completely different

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Jaro-Winkler

• Matching characters defined as letters in name1
  which are within half the length of the name in
  name2. Thus, for two eight-character strings, the
  second letter of name 1 should appear in position
  1 thru 5 of name2

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Jaro-Winkler
J-W
c Number of matching characters s1 Length
of name 1 s2 Length of name 2 t Number of
transpositions
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• However, despite even the most sophisticated
  algorithms for comparing names,
• the weird and wonderful way in which people and
  cultures use names is a problem . . . .

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Nicknames

• James gt Jim, Jimmy
• Elizabeth gt Beth, Liz, Liza, Betsy, Betty
  (Beth could also be short for Bethwyn)
• Margaret gt Meg, Peg, Peggy, Margie
• Raymond gt Ray (commonly also used as a name
  in itself)

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Variant spellings

• Smith, Smythe
• Thomson, Thompson
• Gray, Grey
• Catherine, Katherine, Catharine, Kathryn, Kate
• Brian, Bryan, Bryn

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Changing ethnicity

• Stefan gt Stephen, Steven, Steve
• Josef gt Joseph, Joe
• Giovanni gt John
• Harold Morris gt Harry Maurice
• Smit gt Smith
• Johansson gt Johnson

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Pilgrimages

• Douf gt El Hadji Douf

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Gender indicators

• Vietnamese
• Van indicates male, Thi indicates female
• Dzung Do Van Dzung Do Dzung Van Do

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Family and given name positions

• Jiang Xiao
• Xiao Jiang
• Which is the given name?

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Given name order

• Alfred John Bass
• John Bass
• Alfred Bass
• A John Bass
• John Alfred Bass

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Hyphenated names

• Drake-Brockman
• Lee-Steere
• Owen-Smith gt Smith gt Owen
• De-Klerk

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Names with more than one word

• du Plessis
• el Garrouj
• van der Merwe
• O Day
• Castelnuovo Tedesco

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How many ways can a name appear?

• ODell
• Odell
• O-Dell
• O,Dell
• O Dell

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Name changes

• Marriage
• Adoption
• Divorce
• Forced into hiding
• Personal choice

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• . . . . and, of coarse, people make
  mistakes

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• . . . . and, of course, people make
  mistakes

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• Thank you !