Extra-propositional aspects of meaning in computational linguistics Workshop

Until recently, research in Natural Language Processing (NLP) has focused predominantly on propositional aspects of meaning. For example, semantic role labeling, question answering or text mining tasks aim at extracting information of the type ``who does what, when and where''. However, understanding language involves also processing Extra-Propositional Aspects of Meaning (EPAM), such as factuality, uncertainty, or subjectivity, since the same propositional meaning can be presented in a diversity of statements. While some work on phenomena like subjectivity has been carried out in the context of sentiment processing, other phenomena like the detection of sarcasm have received less attention.

By proposing this workshop we aim at bringing together scientists working on EPAM from any area related to computational language learning and processing. By EPAM we understand aspects of meaning that cannot be captured with a propositional representation such as the output of semantic role labelers.

For instance, the meaning of the sentence in Example (1) can be represented with the proposition ADD(earthquake,further threats to the global economy), whereas representing the meaning of the sentences in Example (2) requires additional mechanisms, despite the fact that all sentences share a propositional meaning.

1. The earthquake adds further threats to the global economy.
2. • Does the earthquake add further threats to the global economy?
   • The earthquake adds further threats to the global economy, doesn't it?
   • The earthquake does not add further threats to the global economy.
   • The earthquake will never add further threats to the global economy.
   • The earthquake will probably add further threats to the global economy.
   • Who could (possibly) think the earthquake adds further threats to the global economy?
   • The earthquake might have added further threats to the global economy.
   • The last analysis show that the earthquake will add further threats to the global economy.
   • It is expected that the earthquake will add further threats to the global economy.
   • It has been denied that the earthquake adds further threats to the global economy.

Some of the sentences above could also be combined in a paragraph such as (3), which shows that the same event can be presented from different perspectives, at different points in time and with different extra-propositional meanings.

3. The main question 6 months ago was whether the earthquake would add further threats to the global economy. Some days after the earthquake the authorities were convinced that it would be possible to minimize the impact of the earthquake. Most economists didn't share this view and predicted a high economic impact of the earthquake. However, a recent study about the earthquake's effect has shown that, although the earthquake might have added further threats to the global economy, its negative impact can be controlled by applying the right measures.

While the area of EPAM comprises a broad range of phenomena, this workshop will focus mainly on the aspects related to modality understood in a general sense (modalities, hedging, certainty, factuality), negation, attitude, and irony/sarcasm. Since many of these phenomena cannot be adequately modeled without taking (discourse) context into account, the workshop also touches on discourse phenomena in so far as they relate to extra-propositional aspects of meaning.