The G lobal W ord N et Formats: Updates for 2020 (2021)

Abstract: The Global Wordnet Formats have been introduced to enable wordnets to have a common representation that can be integrated through the Global WordNet Grid. As a result of their adoption, a number of shortcomings of the format were identified, and in this paper we describe the extensions to the formats that address these issues. These include: ordering of senses, dependencies between wordnets, pronunciation, syntactic modelling, relations, sense keys, metadata and RDF support. Furthermore, we provide some perspectives on how these changes help in the integration of wordnets.

## introduction the introduction of the global wordnet grid @xcite and the collaborative interlingual index @xcite presented a need for greater compatibility between individual wordnet projects through a common format for the representation of wordnets. as such the global wordnet association introduced a format with several serialization methods 1 that have been used by several projects, including the new open english wordnet (ewn; @xcite , the open multilingual wordnet (omw; @xcite and the wn python library @xcite . along with the increased adoption came the perception of shortcomings in the format as it was initially defined, such as the inability to capture all of the information present in princeton wordnet (pwn; @xcite or to capture some key information that other projects wished to use in their modelling. it was therefore deemed necessary to extend the model and, for this reason, we have introduced a new extended version (v1.1) of the format that covers some of these use cases. in this paper, we describe the model as a reference for users and then describe the extensions that have been made to the format. in particular, there are several main areas that have been improved. firstly, the order of words in a synset was not being captured explicitly within the model, which was information that was present in pwn, but did not have a clear semantics. secondly, as many projects build on other projects, either by adding new information @xcite or by translating an existing wordnet, it was felt that it was important to capture the dependencies between projects. in addition, pronunciation information was something that some wordnets have or are in the process of adding, so modelling for this was added. furthermore, we have added some new semantic relations (mainly inspired by plwordnet @xcite . finally, there were some technical issues to do with the modelling of syntactic behaviours, and while the current formats could capture the information, they did so in a way that was quite verbose and lead to bloated files. in addition, we fixed a few minor issues related to the representation of lexicographer files, sense keys and metadata. ## background the global wordnet association's formats are a common data model with three(-plus) serializations in xml, json and various rdf formats. 2 the xml format is based on the lexical markup framework @xcite and in particular on the version developed in the kyoto project @xcite . this represents the wordnet as a lexicalresource with a number of lexicons, one for each language, along with multiple metadata elements about the lexicon, including identifiers, version, language, license, contact email, citation, etc. the format splits the data into two distinct elements, the lexicalentry, which contains the syntactic information about the usage of individual words, and the synset, which provides the semantic information about the synset and the relations to other synsets. the json schema is very close to this and is defined by means of both a json schema description and also a json-ld context, that means that it can be easily interpreted as an rdf file as well. the same example in json is rendered as follows: the rdf version of this as serialized in turtle is very similar and uses the ontolex-lemon vocabu-lary @xcite to express most of the elements along with a small wordnet specific ontology that is published at https://globalwordnet.github . ## discussion and future work in order for wordnets to continue to grow, we have to allow for changes in their structure. in the past, each project has gone ahead on its own, which has led to divergence, with similar changes being implemented in slightly different ways. through the release of a community-driven schema, we can help to harmonise the various projects. this should also lead to the development of interoperable tools, allowing for more rapid development. ideally, we do not just want to make the new format available, but to help projects take advantage of it. for example, the open english word-net may wish to specify its antonym links using the three types (simple, gradable, converse) from plwordnet. we can use the cili to suggest these changes automatically. we would also like to help grow a collection of wordnets available in the new format, both through the open multilingual wordnet or as individual wordnets and extensions. the formats we are proposing fit well with the standardisation initiatives that are on-going around the representation of lexicographic data. as described in this paper we take advantage of both the lexical markup framework @xcite , being developed by iso as well as the on-tolex model @xcite from the w3c. in addition, we are looking at other standardisation efforts such as the lexidma model foot_3 from the oa-sis standardisation body. we are also aware of and taking account of other formats and tools in use in the community including debvisdic @xcite , wordnetloom @xcite and mill. foot_4 ## conclusion the formats proposed by the global wordnet association have already been adopted by some projects and this has provided valuable feedback on the quality. we have found that the open methodology we have adopted has allowed us to quickly address these changes (with some spirited debate). the changes that we have made should ensure that the format continues to be useful and relevant and helps in the integration of wordnets through the collaborative interlingual index.