Integrating pragmatic reasoning in an efficiency-based theory of utterance choice

This thesis explores new methods of accounting for discourse-level linguistic phenomena, using computational modeling. When communicating, efficient speakers frequently choose to either omit, or otherwise reduce the length of their utterances wherever possible. Frameworks such as Uniform Information Density (UID) have argued that speakers preferentially reduce or omit those elements that are more predictable in context, and easier to recover. However, these frameworks have nothing to say about the effects of a linguistic choice on how a message is interpreted. I run 3 experiments which show that while UID posits no specific consequences to being "overinformative" (including more information in an utterance than is necessary), in fact overinformativeness can trigger pragmatic inferences which alter comprehenders' background beliefs about the world. In this case, I show that the Rational Speech Act (RSA) model, which models back-and-forth pragmatic reasoning between speakers and comprehenders, predicts both efficiency-based utterance choices, as well as any consequent change in perceived meaning. I also provide evidence that it's critical to model communication as a lossy process (which UID assumes), which allows the RSA model to account for phenomena that it otherwise is not able to. I further show that while UID predicts increased use of pronouns when referring to more contextually predictable referents, existing research does not unequivocally support this. I run 2 experiments which fail to show evidence that speakers use reduced expressions for predictable elements. In contrast to UID and similar frameworks, the RSA model can straightforwardly predict the results that have been observed to date. In the end, I argue that the RSA model is a highly attractive alternative for modeling speaker utterance choice at the discourse level. When it reflects communication as a lossy process, it is able to predict the same predictability-driven utterance reduction that UID does. However, by additionally modeling back-and-forth pragmatic reasoning, it successfully models utterance choice phenomena that simpler frameworks cannot account for.Diese Arbeit erforscht neue Methoden, linguistische Phänomene auf Gesprächsebene per Computermodellierung zu erfassen. Effiziente Sprecher:innen entscheiden sich bei der Kommunikation häufig dazu, wenn immer es möglich ist, Äußerungen entweder ganz auszulassen oder aber ihre Länge zu reduzieren. Modelle wie Uniform Information Density (UID) argumentieren, dass Sprecher:innen vorzugsweise diejenigen Elemente auslassen, die im jeweiligen Kontext vorhersagbarer und einfacher wiederherzustellen sind. Allerdings sagen diese Modelle nichts über die Auswirkungen einer linguistischen Entscheidung bezüglich der Interpretation einer Nachricht aus. Ich führe drei Experimente durch, die zeigen, dass wenngleich UID keine spezifischen Auswirkungen von "Überinformation" (einer Äußerung mehr Information als nötig geben) postuliert, Überinformationen doch pragmatische Schlussfolgerungen, die das gedankliche Weltmodell der Versteher:innen ändern können, auslöst. Für diesen Fall zeige ich, dass das Rational-Speech-Act-Modell (RSA), welches pragmatische Hin-und-Her-Schlussfolgerungen zwischen Sprecher:innen und Versteher:innen modelliert, sowohl effizienzbasierte Äußerungsauswahl als auch jegliche resultierende Verständnisänderung vorhersagt. Ich liefere auch Anhaltspunkte dafür, dass es entscheidend ist, Kommunikation als verlustbehafteten Prozess zu modellieren (wovon UID ausgeht), was es dem RSA-Modell erlaubt, Phänomene einzubeziehen, wozu es sonst nicht in der Lage wäre. Weiterhin zeige ich, dass obschon UID beim Bezug auf kontextuell vorhersagbarere Bezugswörter eine erhöhte Nutzung von Pronomen vorhersagt, dies von existierender Forschung nicht einstimmig gestützt wird. Ich führe zwei Experimente durch, die keine Anhaltspunkte dafür, dass Sprecher:innen reduzierte Ausdrücke für vorhersagbare Elemente verwenden, finden. Im Gegensatz zu UID und ähnlichen Modellen kann dass RSA-Modell direkt die bislang beobachteten Resultate vorhersagen. Schließlich lege ich dar, warum das RSA-Modell eine höchst attraktive Alternative zur Modellierung von Sprachäußerungsentscheidungen auf Gesprächsebene ist. Wenn es Kommunikation als einen verlustbehafteten Prozess widerspiegelt, kann es dieselbe vorhersagebasierte Äußerungsreduktion vorhersagen wie auch UID. Modelliert man jedoch zusätzlich pragmatische Hin-und-Her-Schlussfolgerungen, modelliert RSA erfolgreich Phänomene bei Äußerungsentscheidungen, die einfachere Modelle nicht abbilden können.German Research Foundation (DFG) as part of SFB 1102 - Information Density and Linguistic Encoding (IDeaL

Relational extensions to feature logic: applications to constraint based grammars

This thesis investigates the logical and computational foundations of unification-based or more appropriately constraint based grammars. The thesis explores extensions to feature logics (which provide the basic knowledge representation services to constraint based grammars) with multi-valued or relational features. These extensions are useful for knowledge representation tasks that cannot be expressed within current feature logics.The approach bridges the gap between concept languages (such as KL-ONE), which are the mainstay of knowledge representation languages in AI, and feature logics. Va¬ rious constraints on relational attributes are considered such as existential membership, universal membership, set descriptions, transitive relations and linear precedence con¬ straints.The specific contributions of this thesis can be summarised as follows: 1. Development of an integrated feature/concept logic 2. Development of a constraint logic for so called partial set descriptions 3. Development of a constraint logic for expressing linear precedence constraints 4. The design of a constraint language CL-ONE that incorporates the central ideas provided by the above study 5. A study of the application of CL-ONE for constraint based grammarsThe thesis takes into account current insights in the areas of constraint logic programming, object-oriented languages, computational linguistics and knowledge representation

Structural and spectroscopic studies on inorganic peroxy compounds

Imperial Users onl

Cleft constructions in discourse

This thesis presents an analysis of the structure and function of cleft constructions in discourse. Drawing on a corpus of naturally-occurring spoken and written data, we present a multi-layered explanation of how it-clefts, wh-clefts, and reverse wh-clefts are different from non-clefts, and from one another. After a review of previous research on clefts in discourse, we explore the aspects of syntax, semantics, and pragmatics relevant to the structure and function of all three types of cleft. The discussion falls into three main parts: An analysis of the three cleft types, within the framework of Generalized Phrase Structure Grammar (cf. Gazdar et al. [1985]), in which particular attention is paid to the variety of constituents that can appear in particular positions in each type. The output of the grammar rules is compared to the examples that occur in the corpus of data. A treatment of cleft presupposition in terms of an analogy (suggested by van der Sandt [1988]) between presupposition and the treatment of pronominal anaphora in Kamp's [1981] Discourse Representation Theory An examination of the range of accentual patterns, presuppositional relations, and information structures typically appearing in clefts of all three kinds. We show that marked distinctions exist between the three cleft types in terms of all these factors, and suggest ways in which this helps to differentiate the range of discourse contexts in which clefts in general, and each cleft type in particular, are appropriate. At the end of the thesis we point to an analogy between the formal model for clefts presented and a psychological model of sentence processing We also suggest how the conclusions regarding both the structure and function of clefts as a class of construction and the distinction between the three types of cleft could be synthesised in a decision procedure for syntactic choice. Finally, we suggest some related areas for further research

Ethnic Inclusion Strategies for the World Affairs Council: A Case Study

The inclusion of people of diverse ethnicities in voluntary organizations is a challenging endeavor. Cultural diversity, rich traditions, historical perspectives, ethnic celebrations, religion, and language are lenses through which leaders of organizations can view the many uniquenesses, differences, and similarities among ethnic groups. The World Affairs Council of San Diego, from January 1,1989 to July 1, 1990, undertook an ambitious community project entitled, Community and Citizen Involvement in Foreign Policy, funded by the Ford Foundation, to increase the participation of ethnic groups, women, and youth in the Council. In this research study, the ethnic inclusion strategies used by the Council are presented and an ethnic inclusion model is developed. The model is comprised of three stages: adoption, implementation, and organizational transformation and is presented for reflection and use by leaders of voluntary organizations. Ethnic diversity in today\u27s post-industrial era is timely. As ethnic populations rapidly increase in the United States, ethnic inclusiveness should be the primary focus of organizations that want to be truly representative of society. Presented in this case study is an in-depth view of twenty voluntary organizations, located in San Diego County, which are representative of four ethnic groups; viz., American Indian, African-American, Asian-American (Filipinos), and Hispanic-American. Ethnic leaders of not-for-profit organizations were interviewed for their opinions and attitudes about ethnic involvement in voluntary organizations. The findings of the study indicated that many of the ethnic voluntary organizations in San Diego were largely expressive groups and mutual-benefit organizations. For a not-for-profit organization to include ethnic members in its organization, all council members must fully understand and participate in the project of ethnic inclusiveness. Future efforts to include ethnic participants in non-ethnic voluntary organizations ought to take into account their needs and interests, and redesign the organization accordingly

Calendar 2020-2021

Academic calendar

From Texts to Prerequisites. Identifying and Annotating Propaedeutic Relations in Educational Textual Resources

openPrerequisite Relations (PRs) are dependency relations established between two distinct concepts expressing which piece(s) of information a student has to learn first in order to understand a certain target concept. Such relations are one of the most fundamental in Education, playing a crucial role not only for what concerns new knowledge acquisition, but also in the novel applications of Artificial Intelligence to distant and e-learning. Indeed, resources annotated with such information could be used to develop automatic systems able to acquire and organize the knowledge embodied in educational resources, possibly fostering educational applications personalized, e.g., on students' needs and prior knowledge. The present thesis discusses the issues and challenges of identifying PRs in educational textual materials with the purpose of building a shared understanding of the relation among the research community. To this aim, we present a methodology for dealing with prerequisite relations as established in educational textual resources which aims at providing a systematic approach for uncovering PRs in textual materials, both when manually annotating and automatically extracting the PRs. The fundamental principles of our methodology guided the development of a novel framework for PR identification which comprises three components, each tackling a different task: (i) an annotation protocol (PREAP), reporting the set of guidelines and recommendations for building PR-annotated resources; (ii) an annotation tool (PRET), supporting the creation of manually annotated datasets reflecting the principles of PREAP; (iii) an automatic PR learning method based on machine learning (PREL). The main novelty of our methodology and framework lies in the fact that we propose to uncover PRs from textual resources relying solely on the content of the instructional material: differently from other works, rather than creating de-contextualised PRs, we acknowledge the presence of a PR between two concepts only if emerging from the way they are presented in the text. By doing so, we anchor relations to the text while modelling the knowledge structure entailed in the resource. As an original contribution of this work, we explore whether linguistic complexity of the text influences the task of manual identification of PRs. To this aim, we investigate the interplay between text and content in educational texts through a crowd-sourcing experiment on concept sequencing. Our methodology values the content of educational materials as it incorporates the evidence acquired from such investigation which suggests that PR recognition is highly influenced by the way in which concepts are introduced in the resource and by the complexity of the texts. The thesis reports a case study dealing with every component of the PR framework which produced a novel manually-labelled PR-annotated dataset.openXXXIII CICLO - DIGITAL HUMANITIES. TECNOLOGIE DIGITALI, ARTI, LINGUE, CULTURE E COMUNICAZIONE - Lingue, culture e tecnologie digitaliAlzetta, Chiar

The Making of a Courtroom: Landlord-Tenant Trials in Philadelphia\u27s Municipal Court

This dissertation analyzes Philadelphia\u27s Landlord-Tenant Court (L-T Court) within organizational and policy contexts. It identifies the factors that influence the outcome of private landlord-tenant trials, describes people\u27s experience of the courtroom from multiple perspectives, and analyzes the Municipal Court\u27s intraorganizational and interorganizational dynamics that inform L-T Court\u27s behavior. Housing courts have been mandated to prevent the deterioration of existing housing stock by protecting landlords\u27 property rights and tenants\u27 rights to a habitable dwelling. Landlords have long had the right to receive rent and to hold tenants responsible for property damage; recent changes in landlord-tenant law have established tenants\u27 right to receive habitable, safe homes. It is only in the protection of both rights that these courts can help preserve affordable, adequate rental housing. This study employs mixed method, single-case study design that utilizes quantitative, case study, and ethnographic methodologies. The combined methods establish a complementary, holistic approach that triangulates methods and data to derive convergent findings. Multiple regression of the judge\u27s identity and actions, litigants\u27 legal strategy, contest participant characteristics, and case characteristics on trial outcomes is based on trial transcript, in-court observation, and court administrative data. Case study analysis is based on interviews with trial participants, including landlords, tenants, attorneys, judges, and court staff and trial transcripts. Ethnographic analysis is based on informal discussions with and observations of disputants, judges, court staff, and others who interact with the court system that surrounds L-T Court. The study also employs a theoretical bundle comprised of autopoiesis, territoriality, paradox theory, and street level bureaucracy to analyze L-T Court\u27s organizational behavior. The study\u27s central finding is that L-T Court propagates substantive and procedural policies that diverge from theoretically binding common law and basic jurisprudential expectations. This divergence can be explained by Municipal Court\u27s organizational dynamics within a legal and regulatory environment. The study concludes that policies designed to strengthen the supply of affordable housing must incorporate the interests of both landlords and tenants. Policy recommendations address the legal representation gap between landlords and tenants, the weak court linkage with legal and administrative organizations, and other areas that prevent effective rental housing regulation