In linguistics, research on dialogue systems has accentuated the need to focus on various pragmatic aspects for their management and modelling. Among the most important pragma-linguistic speech acts in dialogue systems studies are Clarification Requests, corrective feedback that in some circumstances require access to the set of shared knowledge known as Common Ground. Regarding Common Ground management, pragmatic studies suggest differences in the type of polar questions that people prefer be used in Clarification Requests, where polar questions can have two possible answers: true or false. This preference appears to depend on the relationship between bias and contextual evidence. In this work, we show that varying the form of polar questions in a given pragmatic setting can influence the capability of people to track Common Ground inconsistencies. As a result, we demonstrate that using a negative polar question in Italian has functional consequences when communicating conflicting material in the Common Ground. This can improve the quality of human interactions with dialogue systems, in terms of an improved identification of the conflict. The results obtained in this work provide insights into design of error reporting approaches in natural interactions.

This paper analyzes conversational self-repair, which refers to reconstructing problematic portions of a prior oral discourse by oneself, in Tigrinya. Tigrinya is a Northern Ethio-Eritrean-Semitic language spoken by the inhabitants of the Tigray regional state of Ethiopia and Eritrea. This article relies on recorded oral data from speakers of the Rayya Tigrinya variety, particularly inhabitants of Neksege located to the West of Maichew. A conversational analysis (CA) approach is used to analyze the trouble sources, mechanisms (initiators), and results of self-repair. The article shows that pronunciation problems emanating from dialectal variation or tongue slip, wrong word order including focus misplacement, missing constituents, perceived misunderstandings, and using (totally) wrong constituents are some of the trouble sources that push speakers to repair portions of a prior oral utterance. On top of that, cut-offs, particles, and lexemes (one verbal noun and some predicates) are identified as self-repair initiators. Though cut-offs do not indicate a self-repair, particles and predicates may sometimes indicate a self-repair. Finally, the article posits that expanding, replacing, re-ordering, aborting and restarting, and inserting are some of the solutions set for the repairable segments in the repaired portions of the oral discourse. The author recommends for further investigation repair in the process of language acquisition and learning, and the relationship between self-repair and the demographic features of participants.

This paper deals with three interrelated topics, linguistic anaphora, multi-modal anaphora and the top-down broadcasting of information using gestural post-holds in multimodal dialogue. Initially, a new solution for definite, pronominal and pro-adverbial anaphora is given based on the idea that an existentially quantified general term may output a definite reference. This approach is extended to multimodal anaphora, where part or all of an anaphor’s meaning is contributed by some sequence of iconic or deictic gestures. Anaphora exploit the semantic potential of their antecedents, they work, as tradition has it, “bottom-up”. An inverse relation, more general than cataphora, and investigated here for the first time, is “broadcasting”, where information is freely distributed top down and input to receiving sites (ports). Anaphora are modelled with the same top-down mechanism and the same applies for coherence relations in dialogue which generally show an anaphora-like behaviour. “Broadcasting” can be used in the context of anaphors, for example, to provide their gestural meaning parts but also for a verb’s multi-modal arguments for referring to a location, a direction or an area. As to multi-modal data, broadcasting is shown to be frequently tied up with gestural post-holds, the holding of a gesture’s stroke information independently of semantically alignable speech. This leads to considering post-holds from a new perspective, stressing their speech-independent function and their relevance for indicating topic-continuity. We show that multi-modal anaphora and especially broadcasting cross single contributions and turns. The data which let us develop these perspectives come from the SaGA (Speech and Gesture Alignment) corpus, a set of route-description dialogues generated in a VR-setting incorporating marker-based eye-tracking facilities. The calculus used to model the anaphora and broadcasting dynamics is the concurrent λΨ-calculus, a recently developed two-tiered machinery using a Ψ-calculus for input-output, data transport and broadcasting. The data transported are in a typed λ-calculus format incorporating Neo-Davidsonian representations; these data can be linguistic, gestural only or multi-modal. Multi-modal informational chunks are modelled as communicating agents sending and receiving information via input-output-channels. They are introduced incrementally on an empirically motivated construction or gesture-plus-construction or gesture only basis. The λΨ-calculus is also used for the multi-modal fusion component unifying gestural and linguistic information; hence, the paper is also a contribution to multi-modal fusion of linguistic and gestural input. Finally, it is shown how the presented algorithm can capture multi-modal coherence relations or a multi-modal anaphora resolution based on PTT ideas.

The choice of the perspectival center of a stretch of discourse is crucial for the interpretation of certain phenomena such as free indirect discourse. It has been argued that the protagonist that is most prominent compared to competing protagonists gets to be the perspectival center. In this paper we discuss grammatical function and referential expression as prominence-lending cues and their impact on perspective-taking. We take the anchoring of free indirect discourse as the indicator for a shift in perspective as free indirect discourse can only be processed correctly if the reader is able to ascribe the utterance or thought to a protagonist. Identifying the perspectival center is particularly crucial for the interpretation of a thought or utterance in free indirect discourse mode that can potentially be ascribed to different protagonists, since in contrast to direct or indirect discourse the respective speaker or thinker is not explicitly marked as such in free indirect discourse. In a series of acceptability rating studies, we tested if anchoring of free indirect discourse to the less prominent of two competing referents is perceived to be unnatural. Further, we take a closer look at the role of subject and object as well as the choice of referential expression (proper name compared to indefinite noun phrase). We find that a protagonist referred to with a proper name in subject position is highly preferred as the anchor for free indirect discourse compared to a protagonist referred to with an indefinite noun phrase in object position. Building on these findings, we present evidence that the prominence of the referent that is established in the sentence preceding a sentence in free indirect discourse mode can be overridden by discourse prominence. That is, a referent that is repeatedly mentioned in a short discourse is preferred as the perspectival center regardless of the prominence of a competing referent in the sentence preceding a sentence in free indirect discourse mode.

German has two demonstrative pronouns: the der, die, das paradigm and the dieser, diese, dies(es) paradigm. Previous studies mainly compared the anaphoric use of der with the personal pronoun er and observed that der refers to less prominent antecedents. However, there are only very few studies that have investigated the differences between these two demonstrative pronouns. We hypothesize that they differ in signaling topic persistence and in accessing contrastive antecedents. We tested these hypotheses in short texts that manipulated the contrast of the antecedent by inducing the expression ‘in contrast to’ vs. ‘together with’ (e.g., the cellist in contrast to the flautist vs. the cellist together with the flautist). Results from our eye-tracking reading Experiment (Experiment 1), in which participants’ eye- movements were monitored while reading sentences, show that (i) readers preferred dieser when referring to the topic of a sentence, and (ii) dieser caused less processing difficulties than der in both contrast and no-contrast contexts. Our sentence completion Experiment (Experiment 2) also confirmed that der and dieser are both used for anaphoric reference to a topical antecedent. Collectively, our experiments provide evidence that dieser functions as inducing topic persistence. These results suggest that there is a need for further experimental investigation into the semantic factors and informational structures influencing the usage of demonstrative pronouns in German.

In emergency situations users of social networks convey all sorts of what have been called communicative intentions, well-known since the work of Austin (1962) and Searle (1969) as speech acts (SA). While speech acts have been the focus of close scrutiny in the philosophical and linguistic literature (see (Portner, 2018) for extended discussion), their role has been only rarely understood and exploited in processing social media content about crisis events, our focus here. Current work on communicative intentions in social media are topic-oriented, focusing on the correlation between SA and specific topics such as crisis (e.g., earthquakes) but also politics, celebrities, cooking, travel, etc. It has been observed that people globally tend to react to natural disasters with SA distinct from those used in other contexts (e.g., celebrities, which are essentially made up of comments). Here, we explore the further hypothesis of a correlation between different SA types and urgency and propose an in depth linguistic and computational analysis of communicative intentions in tweets from an urgency-oriented perspective. Indeed, SA are mostly relevant to identify intentions, desires, plans and preferences towards action and to ultimately produce a system intended to help rescue teams. Our contribution is four-fold and consists of: (1) A two-layer annotation scheme of speech acts both at the tweet and sub-tweet levels, (2) A new French dataset of about 13K tweets annotated for both urgency and SA, targeting both expected (e.g., storms) and unexpected or sudden (e.g., building collapse, explosion) events, (3) A thorough analysis of the annotations studying in particular the correlation between SA and the urgency of the message, SA and intentions to act categories (e.g., human damages), and SA and crisis types, finally, (4) A set of deep learning experiments to detect SA in crises related corpora. Our results show a strong correlation between SA and urgency annotations at both the tweet and sub-tweet levels with a particular salient correlation in the latter case, which constitutes a first important step towards SA-aware NLP-based crisis management on social media.