Modeling and Contextualizing Claims - Leitura de Artigo

Boland, K., Fafalios, P., Tchechmedjiev, A., Todorov, K., & Dietze, S. (2019). Modeling and Contextualizing Claims. BlockSW/CKG@ISWC.

Abstract.
Understanding societal debates on the Web and how they are impacted by the spread of biased narratives and falsehoods are becoming increasingly important issues. The notion of a claim is central in a number of related studies into fake-news propagation or computational fact-checking.

While the understanding of this notion varies from one field to another, there are few studies that have focused on the conceptual modeling of claims and their context. We attempt to contribute to this area by proposing a novel conceptual model for claims and related notions, such as attitudes, reviews and annotations, that aims to take into consideration the claims inherent complexity, distinguishing between their meaning, linguistic representation and context.

[Modelagem das Alegações e do Contexto associado]

We provide an example of an implementation of this model by using established vocabularies, such as schema.org, Open Annotation and PROV-O, and discuss the challenges related to this work.

[Uso de Ontologias]

Keywords: Claims; Conceptual Modeling; Claim Context; Societal Debates; Fact-checking

1 Introduction

..  the notion of a claim is fundamentally different from the notion of a fact as an atomic assertion in the first-order-logic sense. This is due to the inherent complexity of a claim, where its interpretation usually is strongly dependent on its context, such as its source, timing, or location.

[A relação entre as alegações e o seu contexto é diferente do conceito de FATO em Lógica de Primeira Ordem]

... it is crucial to capture the complexity of a claim in a way which enables unambiguous interpretation by both humans and machines. However, both the used terminology and the underlying conceptual models are still strongly diverging in academic literature as well as in the conceptual models deployed by fact-checking sites.

[Modelo Conceitual]

2 Background

While the analysis of claims plays a crucial role for a number of fields, the definition of the very concept of a claim is often left to the intuition of the reader. Existing definitions vary considerably across and also within fields.

[Três definições para Alegação]

According to the Oxford English Dictionary, a claim is a statement or assertion that something is the case, typically without providing evidence or proof.

Platforms dedicated to journalistic fact-checking refer to claims as statements supported by (a group of) people or organizations that appear newsworthy, significant and verifiable. An RDFS-based model for such fact-checked claims is introduced in [11].

While it is the belief of a person about a fact that is called “claim” in argumentation mining, it is the fact itself that is coined “claim” in the fact-checking community. Similarly, the belief and opinion about certain consequences are the argumentative “claim”, while fact-checking may verify whether the anticipated consequences would indeed follow an action.

Thus, going beyond the model introduced in [11], we propose differentiating between the meaning or proposition of a claim and its utterance, representation and context.

3 Conceptual Model

Overview. We distinguish three main components of a claim, represented by three central classes: (1) claim proposition, (2) claim utterance, and (3) claim context.

A claim proposition is the meaning of a statement or assertion that something is the case. It is usually related to a controversial topic and can be factual or subjective (expressing an opinion). A claim proposition can be expressed in many different ways and in different contexts, thus it has one or more claim utterances. ... On the contrary, a specific claim utterance can be associated to only one proposition, i.e., it has a single meaning. ... Each claim utterance is related to a specific claim context, like the author of the claim or its date. It provides the means to interpret the claim utterance and thus understand its proposition. ... A claim proposition reflects the meaning of one or more semantically equivalent claim utterances expressed in different linguistic forms or contexts.

[Proposição seria a representação formal, Enunciado seria a expressão desta proposição como texto, imagem, vídeo,... e o Contexto estaria associado ao Enunciado (e não a Proposição em si)]

[Com os métodos de Open Information Extraction, os Enunciados em Texto são transformados em Representação em triplas mas o Contexto não é associado]
[O significado e representação formal da Alegação. Por exemplo, a aresta com (id, node1, label, node2) no KGTK]

Claim Utterance. A claim utterance is the act of expressing a claim proposition in a specific natural language and form (like text or speech). Among other things, it may be something said by a politician during an interview, a text within a news article written by a journalist, or a tweet posted by a celebrity about a controversial topic. It is associated with i) one or more linguistic representations (subclass of representation in Fig. 1), and ii) one or more sources (Fig. 2).

[Aqui seria possível linkar a proposição com o conteúdo gerado por usuários nas redes sociais (o enunciado) mas nem sempre é sobre um proposição existente, nem sempre reflete totalmente a proposição, pode até distorcer a proposição roginal dependendo da forma como é escrito o enunciado]

Claim Context. The claim context provides background information about the claim utterance (Fig. 3). Together with the linguistic representation of the claim utterance, it can provide an answer to the Five W’s: i) what was said (linguistic representation of claim utterance), ii) who said it (author of the claim), iii) when it was said (date the claim was said), iv) where it was said (location the claim was said), and v) why it was said (event or activity in the context of which the claim was said). The claim context provides the necessary information for interpreting the claim utterance (and thus understanding its proposition), and can be extended with more concepts that allow describing additional context information about the claim utterance (like the topic of the underlying discourse or the medium used for uttering the claim).

[Perguntas sobre o contexto da Alegação para apoiar o entendimento]

4 RDF Implementation

We introduce an RDF/S implementation of the proposed conceptual model using established vocabularies,

[No meu caso vou assumir como premissa que o vocabulário do esquema é dado, conhecido e não ambíguo]

We make use of the class schema:Claim (currently under integration in schema.org) to describe a claim utterance. According to schema.org, this class represents a specific, factually-oriented claim.

An alternative solution is to bypass the claim context class and directly link an instance of schema:Claim to instances of the four classes connected to the claim context (author, date, location, event). These four classes are described through corresponding schema.org classes: schema:Thing (e.g., a person, an organization, a blog, etc.), schema:Date, schema:Place, schema:Event.

The linguistic representation of a claim utterance, as well as the (preferred) representation of a claim proposition, can be described through the class schema:Text (for textual representations) or schema:MediaObject (for image, audio or video representations). For describing annotations, we make use of the widely-used OA and NIF data models, while provenance information is represented though the PROV data model. 

[As alegações são nós e não arestas. O contexto está associado ao enunciado onde a alegação está sendo expressa como conteúdo gerado pelo usuário e não na proposição em si. ]

5 Concluding Remarks

An open challenge is the detection and representation of the inherent relations between claims as well as their relations to other entities or resources. In particular, the semantic relatedness of claims is reflected by the relations between their proposition components.

[Em um KG as alegações já estão relacionadas]