Gathering Statistics to Aspectually Classify Sentences with a Genetic Algorithm

This paper presents a method for large corpus analysis to semantically classify an entire clause. In particular, we use cooccurrence statistics among similar clauses to determine the aspectual class of an input clause. The process examines linguistic features of clauses that are relevant to aspectual classification. A genetic algorithm determines what combinations of linguistic features to use for this task.Comment: postscript, 9 pages, Proceedings of the Second International Conference on New Methods in Language Processing, Oflazer and Somers ed

MECHANISMS UNDERLYING LEXICAL ACCESS IN NATIVE AND SECOND LANGUAGE PROCESSING OF GENDER AND NUMBER AGREEMENT

Despite considerable evidence suggesting that second language (L2) learners experience difficulties when processing morphosyntactic aspects of L2 in online tasks, the mechanisms underlying these difficulties remain unknown. The aim of this dissertation is to explore possible causes for the difficulties by comparing attentional mechanisms engaged at the early stage of lexical access in native and nonnative language processing. The study utilized a grammatical priming paradigm to examine the manner in which native and L2 speakers of Russian access and integrate morphosyntactic information when processing gender and number agreement that operates between nouns and adjectives within the same noun phrase (e.g., prostoj kozjol "simple-MASC-SG goat-MASC-SG") and between nouns and verbs across phrasal boundaries (e.g., byl kozjol "was-MASC-SG goat-MASC-SG"). While native participants (N=36) invoked both automatic and strategic attentional mechanisms, highly proficient L2 participants (N=36), who had been able to perform at the native-like level in offline tasks, exhibited delayed activation of morphosyntactic information and reliance on strategic mechanisms that operate after lexical access. The finding suggests that L2 difficulties with grammar, that are usually regarded as deficits, may reflect differences in the dynamics of lexical activation. The study also found robust priming effects for both categories and evidence of the Markedness Effect (Akhutina et al, 1999) in both groups of participants: nonnative participants recorded differences in the magnitude of priming between feminines and masculines as well as between singulars and plurals, and native participants showed differential contribution of facilitatory and inhibitory components of priming in response to different genders and numbers. The findings suggest that gender and number may require different processing mechanisms, which, along with salience of morphological markers and agreement structures, may contribute to agreement processing in local dependencies more than syntactic distance

Neuromodulation of Spatial Associations: Evidence from Choice Reaction Tasks During Transcranial Direct Current Stimulation

Various portions of human behavior and cognition are influenced by covert implicit processes without being necessarily available to intentional planning. Implicit cognitive biases can be measured in behavioral tasks yielding SNARC effects for spatial associations of numerical and non-numerical sequences, or yielding the implicit association test effect for associations between insect-flower and negative-positive categories. By using concurrent neuromodulation with transcranial direct current stimulation (tDCS), subthreshold activity patterns in prefrontal cortical regions can be experimentally manipulated to reduce implicit processing. Thus, the application of tDCS can test neurocognitive hypotheses on a unique neurocognitive origin of implicit cognitive biases in different spatial-numerical and non-numerical domains. However, the effects of tDCS are not only determined by superimposed electric fields, but also by task characteristics. To outline the possibilities of task-specific targeting of tDCS, task characteristics and instructions can be varied systematically when combined with neuromodulation. In the present thesis, implicit cognitive processes are assessed in different paradigms concurrent to left-hemispheric prefrontal tDCS to investigate a verbal processing hypothesis for implicit associations in general. In psychological experiments, simple choice reaction tasks measure implicit SNARC and SNARC-like effects as relative left-hand vs. right-hand latency advantages for responding to smaller number or ordinal sequence targets. However, different combinations of polarity-dependent tDCS with stimuli and task procedures also reveal domain-specific involvements and dissociations. Discounting previous unified theories on the SNARC effect, polarity-specific neuromodulation effects dissociate numbers and weekday or month ordinal sequences. By considering also previous results and patient studies, I present a hybrid and augmented working memory account and elaborate the linguistic markedness correspondence principle as one critical verbal mechanism among competing covert coding mechanisms. Finally, a general stimulation rationale based on verbal working memory is tested in separate experiments extending also to non-spatial implicit association test effects. Regarding cognitive tDCS effects, the present studies show polarity asymmetry and task-induced activity dependence of state-dependent neuromodulation. At large, distinct combinations of the identical tDCS electrode configuration with different tasks influences behavioral outcomes tremendously, which will allow for improved task- and domain-specific targeting

Aspect and Meaning in the Russian Future Tense: Corpus and Experimental Investigations

This dissertation is a study of the Russian future tense within the framework of cognitive linguistics. In this dissertation I focus on the distribution of the perfective and imperfective future forms, their future and non-future meanings, and the use of the future tense verb forms by both native and non-native speakers. In the Russian tense-aspect system, it is reasonable to operate with markedness on a local level of tense, rather than the level of the verb. Via local markedness it is possible to see that the perfective future is the unmarked member of the opposition, and the imperfective future is the marked one. The perfective future tense forms are approximately fourteen times more frequent than imperfective future tense forms in the Russian National Corpus. Both perfective and imperfective future tense forms express not only future meanings but also gnomic, directive etc. The (non-)future meanings form a radial category with the future meaning as a prototype and other meanings as extensions. Native speakers operate with frequency when they use future tense forms. Non-native speakers are not sensitive to frequency, and instruction in the use of the future tense forms in Russian could be improved

Second language acquisition of Arabic: the development of negation and interrogation among learners in the U.K.

The study is an investigation of Interlanguage (IL) developmental sequences of the acquisition of some aspects of negation and interrogation in Arabic by English-speaking learners in a foreign- language context; (i.e.Britain).The thesis contains eight chapters. The first chapter discusses the purpose of this research and the reason for selecting the topic.Chapters two and three survey and discuss the relevant literature. This includes discussions of different approaches to Second Language Acquisition (SLA), of models and hypotheses which have been proposed concerning the nature of learners' language and the process of SLA; and of studies of variability in language, both in general and specifically in the field of SLA.In chapter four, we analyze the two structures which are to be investigated in the study. First, basic assumptions of Arabic are discussed. Then, a short, analysis of the form of each structure is presented in both languages (Arabic and English). In the course of the analysis other issues that, are essential for the understanding of the realization of the features in the two languages are discussed.Chapter five presents first the hypotheses concerning the constraints which may govern the learners' IL(s). The rest of the chapter provides details of the investigation. The subjects are described, the tasks outlined, and details of data collection are described. Finally the criteria used in assessing the learners' responses are discussed.In chapter six, the results of the analysis are presented. Chapter seven contains the discussion and interpretation of the results in relation to the hypotheses formulated. The final chapter, chapter eight, summarizes the findings of the study in regard to the hypotheses. It also discusses some of the broader implications of the results of the study. Some suggestions for further investigations are also made

On past participle agreement in transitive clauses in French

This paper provides a Minimalist analysis of past participle agreement in French in transitive clauses. Our account posits that the head v of vP in such structures carries an (accusativeassigning) structural case feature which may apply (with or without concomitant agreement) to case-mark a clause-mate object, the subject of a defective complement clause, or an intermediate copy of a preposed subject in spec-CP. In structures where a goal is extracted from vP (e.g. via wh-movement) v also carries an edge feature, and may also carry a specificity feature and a set of (number and gender) agreement features. We show how these assumptions account for agreement of a participle with a preposed specific clausemate object or defective-clause subject, and for the absence of agreement with an embedded object, with the complement of an impersonal verb, and with the subject of an embedded (finite or nonfinite) CP complement. We also argue that the absence of agreement marking (in expected contexts) on the participles faitmade and laissélet in infinitive structures is essentially viral in nature. Finally, we claim that obligatory participle agreement with reflexive and reciprocal objects arises because the derivation of reflexives involves A-movement and concomitant agreement

The interpretation and use of numerically-quantified expressions

This thesis presents a novel pragmatic account of the meaning and use of numerically-quantified expressions. It can readily be seen that quantities can typically be described by many semantically truthful expressions – for instance, if "more than 12" is true of a quantity, so is "more than 11", "more than 10", and so on. It is also intuitively clear that some of these expressions are more suitable than others in a given situation, a preference which is not captured by the semantics but appears to rely upon on wider-ranging considerations of communicative effectiveness. Motivated by these observations, I lay out a set of criteria that are demonstrably relevant to the speaker's choice of utterance in such cases. Observing further that it is typically impossible to satisfy all these criteria with a single utterance, I suggest that the speaker's choice of utterance can be construed as a problem of multiple constraint satisfaction. Using the formalism of Optimality Theory (Prince and Smolensky 1993), I proceed to specify a model of speaker behaviour for this domain of usage. The model I propose can be used to draw predictions both about the speaker's choice of utterance and the hearer's interpretation of utterances. I discuss the relation between these two aspects of the model, showing how constraints on the speaker's choice of utterance are predicted to make pragmatic enrichments available to the hearer. I then consider applications of this idea to specific issues that have been discussed in the literature. Firstly, with respect to superlative quantifiers, I show how this model provides an alternative account to that of Geurts and Nouwen (2007), building upon that offered by Cummins and Katsos (2010), and I present empirical evidence in its favour. Secondly, I show how this model yields the novel prediction that comparative quantifiers give rise to implicatures that are conditioned both by granularity and by prior mention of the numeral, and demonstrate these implicatures empirically. Finally I discuss the predictions that the model makes about the frequency of quantifiers in corpora, and investigate their validity. I conclude that the model presented here proves its worth as a source of hypotheses about speaker and hearer behaviour in the numerical domain. In particular, it serves as a way to integrate insights from distinct domains of enquiry including psycholinguistics, theoretical semantics and numerical cognition. I discuss the claim of this model to psychological plausibility, its relation to existing approaches, and its potential utility when applied to broader domains of language use.This work was supported by a University of Cambridge (Trinity College) Domestic Research Studentship