Custom 'MetaphoneBR' Phonetic Encoding for Brazilian Names

Simplifies Brazilian names phonetically using a custom 'metaphoneBR' algorithm that preserves ending vowels. Useful for name matching processing preserving gender information carried generally by ending vowels in Portuguese. Mation (2025) .

metaphonebr

The goal of metaphonebr is to simplify brazilian names phonetically using a custom metaphoneBR algorithm that preserves ending vowels, created for aiding in dataset pairing in the absence of unambiguous keys.

Installation

The stable version of the package can be installed with:

install.packages("metaphonebr")

You can install the development version of metaphonebr from GitHub with :

# install.packages("remotes")
remotes::install_github("ipeadata-lab/metaphonebr")

Example

This is a basic example which shows how to use the main function:

example_names <- c("João da Silva", "Maria", "Marya",
                    "Helena", "Elena", "Philippe", "Filipe", "Xavier", "Chavier")
phonetic_codes <- metaphonebr::metaphonebr(example_names)
print(data.frame(original = example_names, metaphonebr = phonetic_codes))

The metaphoneBR phonetic encoding algorithm proceeds as follows:

1. Initial Cleanup & Preparation:
   • Remove all diacritics (e.g., “João” becomes “Joao”).
   • Convert the entire string to uppercase (e.g., “Joao” becomes “JOAO”).
   • Remove all characters that are not uppercase letters (A-Z) or spaces.
   • Ensure single spaces between words and trim leading/trailing whitespace.
2. Silent Letter Removal:
   • Remove a silent ‘H’ if it appears at the beginning of any word (e.g., “Helena” becomes “Elena”).
3. Digraph Simplification (Sound Grouping):
   • LH is replaced by 1 (representing a palatal lateral approximant, like in “Filha” -> “FI1A”).
   • NH is replaced by 3 (representing a palatal nasal, like in “Manhã” -> “MA3A”).
   • CH is replaced by X (representing the /ʃ/ sound, like in “Chico” -> “XICO”).
   • SH is replaced by X (for foreign names with /ʃ/ sound, like in “Shirley” -> “XIRLEY”).
   • SCH is replaced by X (approximating /ʃ/ or /sk/, like in “Schmidt” -> “XMIT”).
   • PH is replaced by F (like in “Philip” -> “FILIP”).
   • SC followed by E or I becomes S (like in “SCENA” -> “SENA”).
   • SC followed by A, O, or U becomes SK (like in “ESCOVA” -> “ESKOVA”).
   • QU or QÜ followed by E or I becomes K (e.g., “QUEIJO” -> “KEIJO”).
   • GU or GÜ followed by E or I becomes G (the U is silent, e.g., “GUERRA” -> “GERRA”).
   • Any remaining QU becomes K (e.g., “QUANTO” -> “KANTO”).
4. Similar Consonant Simplification:
   • Ç is replaced by S.
   • C followed by E or I is replaced by S (like in “CELSO” -> “SELSO”).
   • Any other C (not part of an already transformed digraph like CH or SC) is replaced by K (like in “CARLOS” -> “KARLOS”).
   • G followed by E or I is replaced by J (like in “GELO” -> “JELO”; GUE/GUI already handled).
   • Any remaining Q (that wasn’t part of QU) is replaced by K.
   • W is replaced by V (common Brazilian Portuguese pronunciation, e.g., “WALTER” -> “VALTER”).
   • Y is replaced by I (e.g., “YARA” -> “IARA”).
   • Z is replaced by S (e.g., “ZEBRA” -> “SEBRA”).
   • X preceded by S has the X removed (e.g., “EXCELENTE” -> “ESELENTE”, to avoid a double /s/ representation from SKS).
5. Terminal Nasal Sound Simplification:
   • A word-final N is replaced by M (e.g., “JOAQUIN” -> “JOAQUIM”).
   • A word-final AO is replaced by OM (e.g., “JOÃO” -> “JOOM”).
   • A word-final ÃES is replaced by AES (e.g., “MÃES” -> “MAES”).
6. Duplicate Vowel Removal:
   • Sequences of identical adjacent vowels are reduced to a single vowel (e.g., “AARAO” -> “ARAO”).
7. Final Cleanup (Duplicate Letters & Spaces):
   • Sequences of identical adjacent letters (except if they are part of the special codes 1 for LH or 3 for NH) are reduced to a single letter (e.g., “CARRO” might become “CARO”, “LESSA” becomes “LESA”. Note: This rule simplifies sounds like ‘RR’ and ‘SS’ to their single counterparts, which is a common Metaphone-style simplification).
   • Ensure single spaces between any remaining words and trim leading/trailing whitespace again.

The resulting code is an attempt to represent the phonetic signature of the name in a simplified, standardized way for a Brazilian Portuguese context. In particular, by construction it preserves ending vowels since they imply generally gender information in Brazilian Names (ex.: ADRIANO and ADRIANA).

Note

metaphonebr is developed by a team of researchers at Instituto de Pesquisa Econômica Aplicada (Ipea).