Second Language Sentence Processing: Is it fundamentally different?

In this dissertation, the main assumptions in the Shallow Structure Hypothesis, developed by Clahsen & Felser (2006), are evaluated to determine whether the performance of second language (L2) learners when parsing sentences in the target language is fundamentally different. First, the claim that L2 learners do not employ phrase structure heuristics is assessed with stimuli made up of transitively- and intransitively-biased verbs followed by a noun phrase (Traxler, 2005). The second claim evaluated is that L2 learners do not use structurally defined gaps. This hypothesis is tested by comparing the learners' reading performance of intermediate gaps, stimuli with garden path effects and genitive nominalizations. The third assumption tested involves the use of configurational (binding) principles (Chomsky, 1981) in the parsing of cataphoric reference. The performance of L2 learners of English from Spanish and Chinese backgrounds is compared to that of native English speakers using the moving window paradigm. The relative influence of WM on the processing of these structures was also measured. Results show that both native and non-native speakers present similar parsing profiles and do make use of parsing heuristics. At the same time, both native speakers and L2 learners present difficulties accessing other kinds of structural information and resort instead to other clues that may render 'good-enough' representations (Ferreira et al., 2002). A pervasive finding as regards the WM capacity in L2 learners is the relationship found between the ability to store words and grammatical proficiency in a version of the reading span task (Daneman & Carpenter, 1980)

Learning Functional Prepositions

In first language acquisition, what does it mean for a grammatical category to have been acquired, and what are the mechanisms by which children learn functional categories in general? In the context of prepositions (Ps), if the lexical/functional divide cuts through the P category, as has been suggested in the theoretical literature, then constructivist accounts of language acquisition would predict that children develop adult-like competence with the more abstract units, functional Ps, at a slower rate compared to their acquisition of lexical Ps. Nativists instead assume that the features of functional P are made available by Universal Grammar (UG), and are mapped as quickly, if not faster, than the semantic features of their lexical counterparts. Conversely, if Ps are either all lexical or all functional, on both accounts of acquisition we should observe few differences in learning. Three empirical studies of the development of P were conducted via computer analysis of the English and Spanish sub-corpora of the CHILDES database. Study 1 analyzed errors in child usage of Ps, finding almost no errors in commission in either language, but that the English learners lag in their production of functional Ps relative to lexical Ps. That no such delay was found in the Spanish data suggests that the English pattern is not universal. Studies 2 and 3 applied novel measures of phrasal (P head + nominal complement) productivity to the data. Study 2 examined prepositional phrases (PPs) whose head-complement pairs appeared in both child and adult speech, while Study 3 considered PPs produced by children that never occurred in adult speech. In both studies the productivity of Ps for English children developed faster than that of lexical Ps. In Spanish there were few differences, suggesting that children had already mastered both orders of Ps early in acquisition. These empirical results suggest that at least in English P is indeed a split category, and that children acquire the syntax of the functional subset very quickly, committing almost no errors. The UG position is thus supported. Next, the dissertation investigates a \u27soft nativist\u27 acquisition strategy that composes the distributional analysis of input, minimal a priori knowledge of the possible co-occurrence of morphosyntactic features associated with functional elements, and linguistic knowledge that is presumably acquired via the experience of pragmatic, communicative situations. The output of the analysis consists in a mapping of morphemes to the feature bundles of nominative pronouns for English and Spanish, plus specific claims about the sort of knowledge required from experience. The acquisition model is then extended to adpositions, to examine what, if anything, distributional analysis can tell us about the functional sequences of PPs. The results confirm the theoretical position according to which spatiotemporal Ps are lexical in character, rooting their own extended projections, and that functional Ps express an aspectual sequence in the functional superstructure of the PP

Grounding the Linking Competence in Culture and Nature. How Action and Perception Shape the Syntax-Semantics Relationship

Part I of the book presents my basic assumptions about the syntax-semantics relationship as a competence of language users and compares them with those of the two paradigms that presently account for most theoretical linguistic projects, studies, and publications. I refer to them as Chomskyan Linguistics and Cognitive-Functional Linguistics. I will show that these approaches do not provide the means to accommodate the sociocultural origins of the “linking” competence, creating the need for an alternative approach. While considering these two approaches (sections 2.1 and 2.3), an alternative proposal will be sketched in section 2.2, using the notion of “research programme”. Thus, part I deals mainly with questions of the philosophy of science. Nevertheless, the model underlying the research programme gives structure to the procedure followed throughout the rest of the book, since it identifies the undertaking as multidisciplinary, following from the central roles of perception and action/attribution. This means that approaching the competence of relating form to content as characterized above requires looking into these sub-competences first, since the former draws upon the latter. Part I concludes with the formulation of an action-theoretic vocabulary and taxonomy (section 2.4). This vocabulary serves as the guideline for how to talk about the subject-matter of each of these disciplines. Part II and chapter 3 then deal with the sub-competences that have been identified as underlying linguistic competence. They concern the use of perception, identification/categorization, conceptualization, action, attribution, and the use of linguistic symbols. Section 3.1 in part II deals with perception. In particular, two crucial properties of perception will be discussed: that it consists of a bottom-up part and a top-down part, and that the output of perception is underspecified in the sense that what we perceive is not informative with respect to actional, i.e., socially relevant matters. The sections on perception to some degree anticipate the characterization of conceptualization in section 3.2 because the latter will be reconstructed as simulated perception. The property of underspecification is thus sustained in conceptualization, too. If utterances encode concepts and concepts are underspecified with respect to those matters that are most important for everyday interaction, one wonders how verbal interaction can (actually) be successful. Here is where action competence and attribution come into play (the non-conceptual contents referred to above). I will show that native speakers act and cognize according to particular socio-cognitive parameters, on the basis of which they make socially relevant attributions. These in turn specify what was underspecified about concepts beforehand. In other words, actional knowledge including attribution must complement concepts in order to count as the semantics underlying linguistic utterances. Sections 3.3 and 3.4 develop a descriptive means for semantic contents. I present the inherent structural organization of concepts and demonstrate how the spatial and temporal aspects of conceptualization can be systematically related to the syntactic structures underlying utterances. In particular, I will argue that conceptualization is organized by means of trajector-landmark configurations which can quite regularly be related to parts of speech in syntactic constructions using the notion of diagrammatic iconicity. Given a diagrammatic mapping and conceptualization as simulated perception the utterance thus becomes something like an instruction to simulate a perception. In part III, section 4.1 deals with the question of what the formal constituents of utterances/constructions contribute to the building of a concept from an utterance. In this context a theory of the German dative is presented, based on the theoretical notions developed throughout this work. Section 4.2 sketches the non-formal properties that reduce the remaining underspecification. In this context one of the most fundamental cognitive properties of language users is uncovered, namely their need to find the cause of any event they are cognizing about. I will then outline the consequences of this property for language production and comprehension. Section 4.3 lists the most important linking schemas for German on the basis of the most important constructions, i.e., motivated conceptualization-syntactic construction mappings, and then describes in a step-by-step manner how – from the utterance-as-instruction-for-conceptualization perspective – such an instruction is obeyed, and how such an instruction is built up from the perception of an event, respectively. The last section, 4.4, is dedicated to a discussion of some of the most famous and most puzzling linguistic phenomena which theoretical linguists traditionally deal with. In discussing the formal aspects of the linguistic competence, examples from German are used

The Metalinguistic Buffer Effect: When Language Comprehension is Good but Linguistic Judgment is Only "Good Enough"

Native speakers occasionally report incorrect interpretations of language inputs. For instance, when presented with implausible passive sentences, such as "The dog was bitten by the man", participants sometimes report incorrectly that the dog is the agent of the sentence (Ferreira, 2003). According to the good-enough approach, this error occurs because the language comprehension system sometimes relies on rapid heuristics in favour of structure to determine the meaning of a sentence. This thesis tested the hypothesis that the passive misinterpretation effect is not an error of comprehension, but arises only after interpretation, when participants formulate a thematic judgment of the sentence. It was hypothesized that such thematic judgments involve metalinguistic thinking that can be decoupled from language comprehension processes. This thesis reports the results of two research manuscripts designed to test this hypothesis. In both manuscripts, the methodology involved comparisons of L1 and L2 speakers in single and dual task conditions, which required participants to either report the agents of aurally presented sentences (single task), or to do so while also maintaining six digits in WM (dual task). Because L2 comprehension is more dependent on metalinguistic knowledge than L1 comprehension (Paradis, 2004), it was hypothesized that language status would modulate thematic judgment errors. In Manuscript 1 (Chapter 2), I report the results of two between-subject experiments—one single task and one dual task—which showed that indeed language status modulated the effect. In the single task experiment, there was no difference between L1 and L2 groups. However, in a dual task experiment, the L2 group performed better on the language component of the task (thematic assignment) and worse on the WM component of the task (digit recall). This illustrated that attention allocation to language inputs (at the expense of other tasks) may buttress thematic judgment. In Manuscript 2 (Chapter 4), I report the results of a within-subjects experiment with bilinguals designed to stabilize attention allocation to the different task components, and better isolate the language processing mechanisms that differentiate L1-versus-L2 performance. The data provided evidence for a dissociation between semantic composition and metalinguistic processing in the form of a language-by-load crossover interaction. Bilinguals were better at retrieving the agents of passive sentences in their L2 in the single task condition, but were worse in their L2 in the dual task condition. The pattern suggested that thematic judgments are supported by metalinguistic processes. L2 performance is better in the single task condition because L2 comprehension entails higher initial engagement of metalinguistic representations. In contrast, L1 comprehension depends on implicit semantic compositional processing, which engenders switch costs associated with initiating metalinguistic judgments after interpretation. Critically, because metalinguistic processing is dependent on the control system, the WM load in the dual task condition interfered selectively with L2 comprehension. Thus, L2 performance declined precipitously, while L1 processing remained stable. I conclude that in a native language, “good-enough” heuristics bias metalinguistic conceptualizations of thematic roles post interpretation, and that the underlying semantic composition of passive sentences is fully and faithfully achieved upon an initial analysis by the linguistic system

Knowledge-based methods for automatic extraction of domain-specific ontologies

Semantic web technology aims at developing methodologies for representing large amount of knowledge in web accessible form. The semantics of knowledge should be easy to interpret and understand by computer programs, so that sharing and utilizing knowledge across the Web would be possible. Domain specific ontologies form the basis for knowledge representation in the semantic web. Research on automated development of ontologies from texts has become increasingly important because manual construction of ontologies is labor intensive and costly, and, at the same time, large amount of texts for individual domains is already available in electronic form. However, automatic extraction of domain specific ontologies is challenging due to the unstructured nature of texts and inherent semantic ambiguities in natural language. Moreover, the large size of texts to be processed renders full-fledged natural language processing methods infeasible. In this dissertation, we develop a set of knowledge-based techniques for automatic extraction of ontological components (concepts, taxonomic and non-taxonomic relations) from domain texts. The proposed methods combine information retrieval metrics, lexical knowledge-base(like WordNet), machine learning techniques, heuristics, and statistical approaches to meet the challenge of the task. These methods are domain-independent and automatic approaches. For extraction of concepts, the proposed WNSCA+{PE, POP} method utilizes the lexical knowledge base WordNet to improve precision and recall over the traditional information retrieval metrics. A WordNet-based approach, the compound term heuristic, and a supervised learning approach are developed for taxonomy extraction. We also developed a weighted word-sense disambiguation method for use with the WordNet-based approach. An unsupervised approach using log-likelihood ratios is proposed for extracting non-taxonomic relations. Further more, a supervised approach is investigated to learn the semantic constraints for identifying relations from prepositional phrases. The proposed methods are validated by experiments with the Electronic Voting and the Tender Offers, Mergers, and Acquisitions domain corpus. Experimental results and comparisons with some existing approaches clearly indicate the superiority of our methods. In summary, a good combination of information retrieval, lexical knowledge base, statistics and machine learning methods in this study has led to the techniques efficient and effective for extracting ontological components automatically

Real Language Users

The idea of a perfectly competent but resource limited language user is the basis of many models of sentence comprehension. It is widely assumed that linguistic competence is a) uniform; b) generative; c) autonomous; d) automatic and e) constant. It is also believed that the free expression of these properties is frustrated by limits in the availability of computational resources. However, no firm experimental evidence for the classical language user appears to exist. Negative evidence for each assumption is reviewed here and the notion of resource limitations is shown to be suspect. An experiment is reported which tested each of the five assumptions underlying the conventional notion of linguistic competence. It was found that native speakers of English a) differed in grammatical skill; b) often failed to display productivity; c) violated syntax in favour of plausibility; d) expended conscious effort to comprehend some sentences and e) appeared to adapt to novel structures as the experiment progressed. In line with previous studies, a relationship was found between comprehension skill and formal education. A new finding is that highly educated non-native speakers of English can outperform less educated native speakers of English in comprehending grammatically challenging English sentences. The results indicate that the classical language user is an inaccurate model of real language users, who appear to differ considerably in linguistic skill. A number of specific questions for further research are raised

Analogical specification reuse during requirements analysis

This thesis investigates analogy as a paradigm for retrieving, understanding and customising reusable specifications during requirements engineering. Cooperation between software engineers and support tools is necessary for effective analogical reuse. Retrieval uses a computational implementation of analogical reasoning to search and match many reusable specifications. On the other hand understanding, transferring and adapting specifications requires cooperation between the tool and software engineer. Cooperative support was designed for less-experienced software engineers with most to gain from successful specification reuse. Deliverables from this research have implications for software engineering, artificial intelligence, cognitive science and human-computer interaction. Specification retrieval is founded on a framework of software engineering analogies. This framework includes a set of domain abstractions describing key facts about software engineering domains. A computational model of analogical reasoning which matches domain descriptions to these abstractions was designed, implemented and evaluated during user studies with a prototype reuse advisor. An intelligent dialogue acts as a front-end to this retrieval mechanism by acquiring key domain facts prior to retrieving domain abstractions. This dialogue was designed from empirical studies of software engineering behaviour during requirements capture and modelling. Design of support tools for specification understanding and transfer was based on cognitive task and reasoning models of software engineering behaviour during analogical reuse and mental models of analogical understanding. Two empirical studies of inexperienced software engineers identified problematic mental laziness manifest as specification copying. A third study of expert software engineers who successfully reused specifications identified strategies for effective reuse. Detailed findings from all three studies informed the design of tool-based support for specification understanding and transfer. Findings also have implications for the design of tools to support other requirements engineering activities