From truth conditions to processes: how to model the processing difficulty of quantified sentences based on semantic theory

The present dissertation is concerned with the processing difficulty of quantified sentences and how it can be modeled based on semantic theory. Processing difficulty of quantified sentences is assessed using psycholinguistic methods such as systematically collecting truth-value judgments or recording eye movements during reading. Predictions are derived from semantic theory via parsimonious processing assumptions, taking into account automata theory, signal detection theory and computational complexity. Chapter 1 provides introductory discussion and overview. Chapter 2 introduces basic theoretical concepts that are used throughout the rest of the dissertation. In chapter 3, processing difficulty is approached on an abstract level. The difficulty of the truth evaluation of reciprocal sentences with generalized quantifiers as antecedents is classified using computational complexity theory. This is independent of the actual algorithms or procedures that are used to evaluate the sentences. One production and one sentence picture verification experiment are reported which tested whether cognitive capacities are limited to those functions that are computationally tractable. The results indicate that intractable interpretations occur in language comprehension but also that their verification rapidly exceeds cognitive capacities in case the verification problem cannot be solved using simple heuristics. Chapter 4 discusses two common approaches to model the canonical verification procedures associated with quantificational sentences. The first is based on the semantic automata model which conceives of quantifiers as decision problems and characterizes the computational resources that are needed to solve them. The second approach is based on the interface transparency thesis, which stipulates a transparent interface between semantic representations and the realization of verification procedures in the general cognitive architecture. Both approaches are evaluated against experimental data. Chapter 5 focuses on a test case that is challenging for both of these approaches. In particular, increased processing difficulty of `more than n‘ as compared to `fewer than n‘ is investigated. A processing model is proposed which integrates insights from formal semantics with models from cognitive psychology. This model can be seen as implementation and extension of the interface transparency thesis. The truth evaluation process is conceived of as a stochastic process as described in sequential sampling models of decision making. The increased difficulty of `fewer than n’ as compared to `more than n’ is attributed to an extra processing step of scale-reversal that precedes the actual decision process. Predictions of the integrated processing model are tested and confirmed in two sentence-picture verification experiments. Chapter 6 discusses whether and how the integrated processing model can be extended to other quantifiers. An extension to proportional comparative quantifiers, like `fewer than half’ and `more than half’ is proposed and discussed in the light of existing experimental data. Moreover, it is shown that what are called empty-set effects can be naturally derived from the model. Chapter 7 presents data from two eye tracking experiments that show that `fewer than’ leads to increased difficulty as compared to `more than’ already during reading. Moreover, this effect is magnified if such quantifiers are combined with overt negation. Potential accounts of these findings are discussed. Conclusions are summarized in chapter 8

Respecting Relations: Memory Access and Antecedent Retrieval in Incremental Sentence Processing

This dissertation uses the processing of anaphoric relations to probe how linguistic information is encoded in and retrieved from memory during real-time sentence comprehension. More specifically, the dissertation attempts to resolve a tension between the demands of a linguistic processor implemented in a general-purpose cognitive architecture and the demands of abstract grammatical constraints that govern language use. The source of the tension is the role that abstract configurational relations (such as c-command, Reinhart 1983) play in constraining computations. Anaphoric dependencies are governed by formal grammatical constraints stated in terms of relations. For example, Binding Principle A (Chomsky 1981) requires that antecedents for local anaphors (like the English reciprocal each other) bear the c-command relation to those anaphors. In incremental sentence processing, antecedents of anaphors must be retrieved from memory. Recent research has motivated a model of processing that exploits a cue-based, associative retrieval process in content-addressable memory (e.g. Lewis, Vasishth & Van Dyke 2006) in which relations such as c-command are difficult to use as cues for retrieval. As such, the c-command constraints of formal grammars are predicted to be poorly implemented by the retrieval mechanism. I examine retrieval's sensitivity to three constraints on anaphoric dependencies: Principle A (via Hindi local reciprocal licensing), the Scope Constraint on bound-variable pronoun licensing (often stated as a c-command constraint, though see Barker 2012), and Crossover constraints on pronominal binding (Postal 1971, Wasow 1972). The data suggest that retrieval exhibits fidelity to the constraints: structurally inaccessible NPs that match an anaphoric element in morphological features do not interfere with the retrieval of an antecedent in most cases considered. In spite of this alignment, I argue that retrieval's apparent sensitivity to c-command constraints need not motivate a memory access procedure that makes direct reference to c-command relations. Instead, proxy features and general parsing operations conspire to mimic the extension of a system that respects c-command constraints. These strategies provide a robust approximation of grammatical performance while remaining within the confines of a independently- motivated general-purpose cognitive architecture

Comprehending Each Other: Weak Reciprocity and Processing

This dissertation looks at the question of how comprehenders get from an underspecified semantic representation to a particular construal. Its focus is on reciprocal sentences. Reciprocal sentences, like other plural sentences, are open to a range of interpretations. Work on the semantics of plural predication commonly assumes that this range of interpretations is due to cumulativity (Krifka 1992): if predicates are inherently cumulative (Kratzer 2001), the logical representations of plural sentences underspecify the interpretation (rather than being ambiguous between various interpretations). The dissertation argues that the processor makes use of a number of general preferences and principles in getting from such underspecified semantic representations to particular construals: principles of economy in mental representation, including a preference for uniformity, and principles of natural grouping. It sees no need for the processor to make use of a principle like the Strongest Meaning Hypothesis (Dalrymple et al. 1998) in comprehending reciprocal sentences. Instead, they are associated with cumulative semantic representations with truth conditions equivalent to Weak Reciprocity (Langendoen 1978), as in Dotlačil (2010). Interpretations weaker than Weak Reciprocity (‘chain interpretations’) arise via a process of pragmatic weakening. Interpretations stronger than Weak Reciprocity may arise in different ways. Statives are seen as having special requirements regarding the naturalness or ‘substantivity’ of pluralities (Kratzer 2001), and this leads to stronger readings. In other cases, strong interpretations are favoured by a preference for uniformity, which is taken to be a type of economy preference. It is assumed that the processor need not commit to a fully spelled out construal, but may build mental models of discourse that themselves underspecify the relations that hold among individuals. While the dissertation’s focus is on reciprocal sentences, the same principles and preferences are argued to be involved in comprehending other plural sentences

A Dichotomy Result for Ramsey Quantifiers

Abstract. Ramsey quantifiers are a natural object of study not only for logic and computer science, but also for formal semantics of natu-ral language. Restricting attention to finite models leads to the natural question whether all Ramsey quantifiers are either polynomial-time com-putable or NP-hard, and whether we can give a natural characterization of the polynomial-time computable quantifiers. In this paper, we first show that there exist intermediate Ramsey quantifiers and then we prove a dichotomy result for a large and natural class of Ramsey quantifiers, based on a reasonable and widely-believed complexity assumption. We show that the polynomial-time computable quantifiers in this class are exactly the constant-log-bounded Ramsey quantifiers.

Proceedings of the 2010 Annual Conference of the Gesellschaft für Semantik

Sinn & Bedeutung - the annual conference of the Gesellschaft für Semantik - aims to bring together both established researchers and new blood working on current issues in natural language semantics, pragmatics, the syntax-semantics interface, the philosophy of language or carrying out psycholinguistic studies related to meaning. Every year, the conference moves to a different location in Europe. The 2010 conference - Sinn & Bedeutung 15 - took place on September 9 - 11 at Saarland University, Saarbrücken, organized by the Department for German Studies

Anaphora resolution for Arabic machine translation :a case study of nafs

PhD ThesisIn the age of the internet, email, and social media there is an increasing need for processing online information, for example, to support education and business. This has led to the rapid development of natural language processing technologies such as computational linguistics, information retrieval, and data mining. As a branch of computational linguistics, anaphora resolution has attracted much interest. This is reflected in the large number of papers on the topic published in journals such as Computational Linguistics. Mitkov (2002) and Ji et al. (2005) have argued that the overall quality of anaphora resolution systems remains low, despite practical advances in the area, and that major challenges include dealing with real-world knowledge and accurate parsing. This thesis investigates the following research question: can an algorithm be found for the resolution of the anaphor nafs in Arabic text which is accurate to at least 90%, scales linearly with text size, and requires a minimum of knowledge resources? A resolution algorithm intended to satisfy these criteria is proposed. Testing on a corpus of contemporary Arabic shows that it does indeed satisfy the criteria.Egyptian Government

Proceedings of the Sixth International Conference Formal Approaches to South Slavic and Balkan languages

Proceedings of the Sixth International Conference Formal Approaches to South Slavic and Balkan Languages publishes 22 papers that were presented at the conference organised in Dubrovnik, Croatia, 25-28 Septembre 2008

Situations and individuals

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Linguistics and Philosophy, 2002.Includes bibliographical references (p. 220-233).I argue that definite descriptions, pronouns and proper names share one common syntax and semantics, basically that of definite descriptions. E-type pronouns are argued to be definite articles that take NP complements elided in the phonology; referential and bound variable pronouns are analyzed as definite articles taking indices as phonologically null complements. Proper names are shown to have previously undetected E-type and bound readings, meaning that they too are best regarded as definite descriptions. It is shown that this position has deleterious consequences for the philosophical theories of direct reference and rigid designation.by Paul Elbourne.Ph.D

Proceedings of the Conference "sub8 - Sinn und Bedeutung" : 8th annual meeting of the Gesellschaft für Semantik

The volume is a collection of papers given at the conference “sub8 -- Sinn und Bedeutung”, the eighth annual conference of the Gesellschaft für Semantik, held at the Johann-Wolfgang-Goethe-Universität, Frankfurt (Germany) in September 2003. During this conference, experts presented ­ and discussed ­ various aspects of semantics. The very different topics included in this book provide insight into fields of ongoing Semantics research.Mit dem vorliegenden Band halten Sie eine Sammlung von Aufsätzen in Händen, die bei "Sinn und Bedeutung VIII", der Jahrestagung der "Gesellschaft für Semantik" in der Johann Wolfgang Goethe-Universität, Frankfurt/Main, im September 2003 vorgestellt worden sind. Die Beiträge umfassen verschiedenste Aspekte aktueller Semantik-Forschung und lassen sich inhaltlich den folgenden Kategorien zuordnen: (i) Semantik von Topic und Focus [Ebert / Endriss, Gyuris, Kaiser / Trueswell, Lee, Umbach, Wedgewood]; (ii) Semantik und Pragmatik von Fragen [Beck, Benz, Dekker]; (iii) Semantik von Tense und Voice [Fernando, Lekaku, Sailer]; (iv) Das Syntax-Semantik Interface [Kobuchi-Philip, Stateva, Zeijlstra], (v) Modalität [van Rooy, Copley] und (vi) Semantik [Aksan, Nicolas, Schäfer, Schlücker, Seong, Zwarts]