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This workflow tutorial takes you through the steps in order to create a paralex lexicon.


Creating the data is of course the hardest task. You have full freedom to do this in whatever way feels most practical or convenient for you and your team. This might mean editing csv files directly in LibreOffice Calc or Microsoft Excel, manipulating raw data using a programming language like R or Python, relying on some sort of database manager with a graphical interface, or anything else you can think of. Before publication, you need to be able to export each table in csv format with a utf-8 character encoding.

The python package paralex allows you to then generate additional metadata in accordance with the standard automatically.


The set of expected tables are described in the description of the standard. Minimally, you should have a forms table which documents forms, and has at least the three columns form_id, lexeme, cell and phon_form (or orth_form). The standard also specified the following tables:

  • a lexemes table to document lexeme-level information such as inflection class.
  • a cells table to document the meaning of each cell identifier,
  • a features table to document the meaning of each feature in the each cell,
  • a sounds table to document the conventions used to write the phon_form,
  • a grapheme table to document the conventions used to write the orth_form,
  • a tags table to document the labels for sets of forms related by properties such as overabundant series, defectivity type, dialectal variants, or data quality.

See specs for the detail of expected tables and columns. Any additional ad-hoc tables and columns can be added as necessary.


Adding Metadata

The python package paralex can generate metadata automatically, filling-in default information whenever the standard conventions are used. Technically speaking, it will create a single metadata file with a name ending in .package.json. You should then see all of your dataset and associated metadata as a single "package" described by the metadata file.

First, you need to install paralex. This can be done from the command line, for example as follows:

Installing paralex
pip3 install paralex

Let's assume you have a single table of data, documenting Vulcan verbal paradigms. You can generate the metadata, to be placed in a file vulcan.package.json automatically. To do so you will need to prepare a python script within a text document as follows:
from paralex import paralex_factory

package = paralex_factory("Vulcan Verbal Paradigms",
                              "forms": {"path": "vulcan_v_forms.csv"},

This script states the title of your package and that you will be using a single table which documents forms, currently located in your file vulcan_v_forms.csv. Paralex will create metadata for your package, using information from the standard whenever you used standard columns, and inferring it from the data elsewhere.

The example above is minimal: a title for the package and at least a paradigm table with a specific path is necessary. However, we recommend you add more information in your script. In particular, provide a full text citation specifying how you wish your dataset to be cited, a list of collaborators following the [frictionless specification] (, a license, a DOI identifier:
from paralex import paralex_factory

package = paralex_factory("Vulcan Verbal Paradigms",
                              "forms": {"path": "vulcan_v_forms.csv"},
                          citation="Spock (2258). Vulcan Verbal Paradigms dataset. Online.",
                          keywords=["vulcan", "paradigms"],
                          contributors=[{'title': 'Spock', 'role': 'author'},
                          licenses=[{'name': 'CC-BY-SA-4.0',
                                     'title': 'Creative Commons Attribution Share-Alike 4.0',
                                     'path': ''}]

If this script is saved under the name and is placed in the same folder as the csv table, you can run it by typing in the terminal:

Generating metadata

The same process applies if you have more tables. Here is an example with a full list of five tables, including vulcan_v_cells.csv, vulcan_v_features.csv, vulcan_v_lexemes.csv, vulcan_v_phonemes.csv:
from paralex import paralex_factory

package = paralex_factory("Vulcan Verbal Paradigms", {
    "cells": {"path": "vulcan_v_cells.csv"},
    "forms": {"path": "vulcan_v_forms.csv"},
    "features-values": {"path": "vulcan_v_features.csv"},
    "lexemes": {"path": "vulcan_v_lexemes.csv"},
    "phonemes": {"path": "vulcan_v_phonemes.csv"}
citation = "Spock and al (2258). Vulcan Verbal Paradigms dataset. Online.",
version = "1.0.2",
keywords = ["vulcan", "paradigms", "paralex"],
id = "",
contributors = [{'title': 'Spock', 'role': 'author'},
  licenses=[{'name': 'CC-BY-SA-4.0',
             'title': 'Creative Commons Attribution Share-Alike 4.0',
             'path': ''}]

Ensuring high quality data

Frictionless validation

The metadata generated above, and saved in the json file vulcan.package.json can now be used to validate the dataset using frictionless. Frictionless should have been installed as a dependency when you installed paralex. You can now run:

Checking against the metadata
frictionless validate vulcan.package.json

This will check that all the tables exist and are well formed, and that columns contain the types and contents declared by the metadata file, and that any constraints on columns (such as being a value from a specific set of predefined values, being unique, being obligatory, having maximum or minimum values, etc) are respected. Note that the following requirements will also be checked for:

  • All identifiers MUST be unique, that is to say, no two rows in their table has the same value in form_id, cell_id, lexeme_id, feature_id, or phoneme_id.
  • All values in the cell column of the forms MUST correspond to an identifier in cell_id of the cells table if it exists;
  • All values in the lexeme column of the forms MUST correspond to an identifier in lexeme_id of the lexemes table if it exists
  • If there is a phonemes table, then the phon_form in forms MUST be composed only of phoneme identifiers and spaces.
  • If there is a cells table and a features table, then the cell_id in cells MUST be composed only of feature identifiers found in feature_id, separated by dots, following the Leipzig glossing rules convention.

Paralex validation

Any frictionless dataset can be checked against its metadata. In addition, to check that the dataset is in fact a paralex lexicon, you can use the paralex validate command as follows:

Checking against the standard itself
paralex validate vulcan.package.json

This attempts to check all of the MUST and SHOULD statements from the standard. This is a possible output:

───────────────────────────────────────── Paralex validation ─────────────────────────────────────────

Checking MUSTs...
These are mandatory: any failing statement needs to be corrected for the dataset to comply with 
- ✔ pass frictionless validation
- ✔ Has a readme file
- ✔ Has a forms table
- ✔ Forms table minimally defines triplets
- ✔ Has all expected relations
-  (No tags used)
- ✔ Has vocabulary constraints
- ✔ Phonological forms, if present, are space separated.
- ✔ Cell format is correct

Looking for potential issues...
These are indicative: any failing statement might indicate a problem, you should check.
-  (No analysis columns).
- ✔ Defines sounds explicitly
- ✔ Inflected forms seem atomic (no separators found).
- ✔ It seems that cells are mapped to other vocabularies.
- 🏴 It seems that features are not mapped to any other vocabulary
 Add mappings (eg. to UD, unimorph, other corpora schemes) to improve interoperability
- ✔ It seems that sounds have definitions or labels.

Checking SHOULDs...
These are recommendations: any failing statement indicates a potential improvement of the dataset.
- ✔ Dataset has all recommended tables
- ✔ It seems that cells are mapped to multiple vocabularies.
- ✔ Dataset has ids in the right place
- ✔ Form table has phon_form column
- 🏴 Could not find any data sheet file
 Add a data sheet!


In addition, you might want to check or to constrain additional properties of the data. Some constraints can be expressed in the package metadata, see the frictionless doc on constraints.

For more checks, we recommend writing tests in the programming language of your choice, which read the data and automatically verify sets of expected properties. For example, you might want to check:

  • That the number of rows in each table conforms to your expectations (thereby checking that you did not add rows anywhere by mistake)
  • Complex verifications on the phonological form (this serves to avoid obvious mistakes in the phonemic transcriptions), for example ensuring that every word has a stress marker.
  • Logical properties: for example, that defective forms do not have positive frequencies
  • etc.


The raw data files

We recommend publishing the completed dataset as an online repository, such as on github or gitlab.

The repository should contain:

  • the data, in the form of csv tables
  • the metadata, in the form of a json file (this is a frictionless package file)
  • the documentation files, at the minimum a file
  • a license file
  • the code:
    • the metadata python script
    • the tests if they exist
    • when possible, legal, and practical: a link to any automated process used to generate the data, or any related repository used to generate it.


We recommend archiving the data by creating a record on some archival service, for example zenodo. A good practice would be to set up automatic archives for new versions. This can be done natively from github, or can be done using gitlab2zenodo.

To have your dataset officially listed as a paralex lexicon, add it to the zenodo community