P rop B ank goes Public: Incorporation into W ikidata (2024)

Abstract: This paper presents the first integration of PropBank role information into Wikidata, in order to provide a novel resource for information extraction, one combining Wikidata’s ontological metadata with PropBank’s rich argument structure encoding for event classes. We discuss a technique for PropBank augmentation to existing eventive Wikidata items, as well as identification of gaps in Wikidata’s coverage based on manual examination of over 11,300 PropBank rolesets. We propose five new Wikidata properties to integrate PropBank structure into Wikidata so that the annotated mappings can be added en masse. We then outline the methodology and challenges of this integration, including annotation with the combined resources.

## introduction recent work @xcite has explored how wikidata @xcite can be adapted as an ontology for information extraction by: (1) providing an external resource that augments existing eventive wikidata items with propbank @xcite @xcite role information; and (2) documenting gaps of event coverage in wikidata, where a propbank concepts have no corresponding wikidata items. for each propbank predicate, annotators have been asked to identify a matching concept in wikidata. all 11,300+ prop-bank rolesets have been subject to at least one pass of this task, so that each propbank predicate has either a wikidata mapping or a flag indicating a missing concept in wikidata. this paper outlines the methodology and challenges of integrating the project into wikidata itself, including filling those gaps in event coverage. the paper will also document the unique annotation challenges faced in attempting to join the two different resources. each item in wikidata refers to either a concept ("planet") or a real-world instantiation of a concept ("earth"), and is uniquely identified by a q followed by a string of digits. relations are called properties in wikidata, and are uniquely identified by a p followed by a string of digits. wikidata items can have statements, which are a property and a value (usually another item or a static data point such as a string or numerical quantity). thus, <subject, relation, @xmath0, property, @xmath1. statements can be annotated with qualifiers-for example, specifying the start and end time that a relation holds-and references, making wikidata an extremely rich, detailed, and verifiable source of knowledge for natural language processing ap-plications. additionally, wikidata is a multilingual resource. users can browse and add data to wikidata in their preferred language, so concepts can be described by labels written in a broad range of languages, with an average of around 8 labels foot_1 per wikidata item. ## the events and role frames wikiproject to address the issues discussed in section 2. ## challenges to incorporation of propbank into wikidata an inherent challenge to integration is inevitable discrepancies between projects. as a database of coarse-grained, predicate-specific semantic frames, propbank entries are eventive in nature. while entries may be nominal, adjectival, or verbal, the majority are verbal. by contrast, the wikidata database includes comparatively fine-grained entries for events and entities, in addition to a number of other types of items. the majority of wikidata entities are nominal and often non-eventive in nature. differences in item granularity and item type necessitate careful comparisons of the scope of a roleset to the scope of an item. sometimes items have better mappings to predicate arguments than to the predicates themselves, raising the question of whether such argument mappings are useful. managing these differences has been largely guided by the utility of the overlay in downstream tasks. ## improving dwd utility the overlay's development has been closely guided by feedback from users of the overlay. currently, the overlay is used for event extraction on newstext, so many of the changes and additions made to the overlay have been informed by the effect the change might have on that task. ## conclusion the project of merging propbank into wikidata presents unique annotation challenges. wikidata is highly entity-centric, making it difficult to identify good candidates for mapping to propbank: moreover, differing granularity between verb senses in propbank and concepts in wikidata has proved to be one of the foremost challenges of mapping between resources, even when an eventive wikidata item exists. our approach to managing many of these challenges has been to prioritize feedback from the users of the overlay, allowing the needs of the information extraction use case to guide us. on top of the linguistic challenges, organizational and logistical challenges abound. propbank is a relatively static resource that was annotated by linguistic experts. wikidata is a constantly changing project maintained and compiled by anyone with an internet connection. while the overlay has a well-defined use case-event and argument extraction from natural language text-wikidata has so many different users and stakeholders that it is difficult to claim that there is any one use case for the resource. our current approaches for managing the challenges of propbank-wikidata linking, therefore, may need to be adjusted as we work with the wikidata community to integrate our mappings into wikidata itself.