Developing a corpus of strategic conversation in The Settlers of Catan

International audienceWe describe a dialogue model and an implemented annotation scheme for a pilot corpus of annotated online chats concerning bargaining negotiations in the game The Settlers of Catan. We will use this model and data to analyze how conversations proceed in the absence of strong forms of cooperativity, where agents have diverging motives. Here we concentrate on the description of our annotation scheme for negotiation dialogues, illustrated with our pilot data, and some perspectives for future research on the issue

Strategic Conversation

International audienceModels of conversation that rely on a strong notion of cooperation don’t apply to strategic conversation — that is, to conversation where the agents’ motives don’t align, such as courtroom cross examination and political debate. We provide a game-theoretic framework that provides an analysis of both cooperative and strategic conversation. Our analysis features a new notion of safety that applies to implicatures: an implicature is safe when it can be reliably treated as a matter of public record. We explore the safety of implicatures within cooperative and non cooperative settings. We then provide a symbolic model enabling us (i) to prove a correspondence result between a characterisation of conversation in terms of an alignment of players’ preferences and one where Gricean principles of cooperative conversation like Sincerity hold, and (ii) to show when an implicature is safe and when it is not

Modelling Strategic Conversation: model, annotation design and corpus

International audienceA Gricean view of cognitive agents holds that agents are fully rational and adhere to the maxims of conversation that entail that speakers adopt shared intentions and fully aligned preferences–e.g. (Allen and Litman, 1987; Lochbaum, 1998). These assumptions are unwarranted in many conversational settings. In this paper we propose a different view and an annotation scheme for it

Structural and biochemical characterisation of the C-type lectin receptor DNGR 1 and its binding to F-actin

DNGR-1 is a C-type lectin receptor that has been implicated in the regulation of endocytic trafficking and cross-presentation of dead cell-associated antigens. Dendritic cells deficient in DNGR-1 are impaired in priming effector T-cell responses against cytopathic viruses and other dead cell-associated antigens. The ligand for DNGR-1 is the polymerized form of actin (F-actin) revealed in dead cells upon loss of membrane integrity. In this study we set out to determine biophysical, biochemical, and structural properties of DNGR-1 and its interaction with F-actin. First, we describe a conformational change that occurs in the neck region of the receptor in a pH- and ionic strength-dependent manner. Notably, the conformational change happens between conditions corresponding to the extracellular environment and the environment present in the vesicles of the endosomal pathway respectively, suggesting a possible role in the spatial regulation of the DNGR-1 function. Second, in collaboration with Keichii Namba and Takashi Fujii (RIKEN Quantitative Biology Center, Osaka, Japan) we used electron cryomicroscopy to solve the structure of DNGR-1 bound to F-actin at 7.7 Å resolution. Interestingly, DNGR-1 binds into the groove between actin protofilaments, making contacts with three actin subunits that are helically arranged in the F-actin structure. We identify the residues directly involved in the interaction, confirm their contribution to the binding and demonstrate the importance of avidity of the multivalent interaction between DNGR-1 and F-actin. Additionally, in collaboration with David Sancho and Salvador Iborra (Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain) we formally demonstrate that ligand recognition is prerequisite for the biological function of DNGR-1 in dendritic cells. Third, by using heterodimeric DNGR-1 proteins in which one half of the dimer is incapable of binding to ligand, we demonstrate that DNGR-1 can bind with both ligand binding domains to a single actin filament, suggesting an exceptional flexibility of the neck region, and demonstrating an absence of rigid dimerization interface between the ligand-binding domains. In summary, we provide a comprehensive description of the structural and biophysical properties of DNGR-1, offering novel insights into its function and shedding light into innate immune mechanisms involved in recognition of cell death

The drama of Senkatana by S.M. Mofokeng : a speech act exploration

The drama of Senkatana by S.M. Mofokeng is analysed by applying principles provided by speech act theory, using as basis the explication of the theory by Bach and Harnish (1979). The socio-cultural context in the play has as its starting point the realm of myth and legend. From here all categories of relationships within the protagonist/antagonist encounter unfold, as do opposing sets of contextual beliefs characters rely on; these are primarily responsible for the growing conflict in the drama. Enhancing the mythical character of the play is the absorbing role played by the diboni, acting as seers, as prophets and as additional 'authorial voice'. Their and those of other characters' speech acts reflect this and more; they operate in a substantiated sign-system which provides a framework for evaluating each semiotic act from locutionary, illocutionary and perlocutionary dimensions of meaning. Chapter 1 comprises a historical survey of studies on speech act theory, and includes a brief summary of the position of the theory in the field of semiotics. The micro speech act analysis of the play is facilitated by the division of the text into smaller action units (summarised in Addendum 1). Chapter 2, containing the greater part of the exposition, commences the narration of the folktale and offers a clear rendering of the epic rise of the hero. Chapter 3 portrays the rise and progress of the antagonists challenging the hero, coupled with intensifying anxiety among the protagonists. Chapter 4 provides a vivid overview of how the values of the hero triumph over those of the antagonist despite the physical slaying of the hero. Chapter 5 offers a graphic outline of how the macro speech act is accomplished in the play. It is shown how an investigation of the speech act profiles of characters, coupled with the evaluation of illocutionary tactics and illocutionary/perlocutionary dynamics, communicates significant information pertaining to characterisation. A graph illustrating the rise and fall of micro speech acts within the larger macro speech act is provided in Addendum 2. Suggestions are made regarding future research in literary texts.African LanguagesD.Lit. et Phil. (African Languages

Semantics and pragmatics in a modular mind

This dissertation asks how we should understand the distinction between semantic and pragmatic aspects of linguistic understanding within the framework of mentalism, on which the study of language is a branch of psychology. In particular, I assess a proposal on which the distinction between semantics and pragmatics is ultimately grounded in the modularity or encapsulation of semantic processes. While pragmatic processes involved in understanding the communicative intentions of a speaker are non-modular and highly inferential, semantic processes involved in understanding the meaning of an expression are modular and encapsulated from top-down influences of general cognition. The encapsulation hypothesis for semantics is attractive, since it would allow the semantics-pragmatics distinction to cut a natural joint in the communicating mind. However, as I argue, the case in favor of the modularity hypothesis for semantics is not particularly strong. Many of the arguments offered in its support are unsuccessful. I therefore carefully assess the relevant experimental record, in rapport with parallel debates about modular processing in other domains, such as vision. I point to several observations that raise a challenge for the encapsulation hypothesis for semantics; and I recommend consideration of alternative notions of modularity. However, I also demonstrate some principled strategies that proponents of the encapsulation hypothesis might deploy in order to meet the empirical challenge that I raise. I conclude that the available data neither falsify nor support the modularity hypothesis for semantics, and accordingly I develop several strategies that might be pursued in future work. It has also been argued that the encapsulation of semantic processing would entail (or otherwise strongly recommend) a particular approach to word meaning. However, in rapport with the literature on polysemy—a phenomenon whereby a single word can be used to express several related concepts, but not due to generality—I show that such arguments are largely unsuccessful. Again, I develop strategies that might be used, going forward, to adjudicate among the options regarding word meaning within a mentalistic linguistics