940 resultados para Explanatory power
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Deviations of policy interest rates from the levels implied by the Taylor rule have been persistent before the financial crisis and increased especially after the turn of the century. Compared to the Taylor benchmark, policy rates were often too low. This paper provides evidence that both international spillovers, for instance international dependencies in the interest rate-setting of central banks, and nonlinear reaction patterns can offer a more realistic specification of the Taylor rule in the main industrial countries. The inclusion of international spillovers and, even more, nonlinear dynamics improves the explanatory power of standard Taylor reaction functions. Deviations from Taylor rates tend to be smaller and their negative trend can be eliminated.
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Thesis (Ph.D.)--University of Washington, 2016-06
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The neurodevelopmental hypothesis (NDH) of schizophrenia suggests that a disruption of brain development during early life underlies the later emergence of psychosis during adulthood. The aim of this review is to chart the challenges and subsequent refinements to this hypothesis, with particular reference to the static versus progressive nature of the putative neurobiological processes underlying the NDH. A non-systematic literature review was undertaken, with an emphasis on major review papers relevant to the NDH. Weaknesses in the explanatory power of the NDH have led to a new generation of more refined hypotheses in recent years. In particular, recent versions of the hypothesis have incorporated evidence from structural neuroimaging which suggests changes in brain volumes after the onset of schizophrenia. More detailed models that incorporate progressive neurobiological processes have replaced early versions of the NDH, which were based on a 'static encephalopathy. In addition, recent models have suggested that two or more 'hits' are required over the lifespan rather than only one early-life event. Animal models are providing important insights into the sequelae of disturbed early brain development. The NDH has provided great impetus to the schizophrenia research community. Recent versions of the hypothesis have encouraged more focused and testable hypotheses.
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The present study adds to the sparse published Australian literature on the size effect, the book to market (BM) effect and the ability of the Fama French three factor model to account for these effects and to improve on the asset pricing ability of the Capital Asset Pricing Model (CAPM). The present study extends the 1981–1991 period examined by Halliwell, Heaney and Sawicki (1999) a further 10 years to 2000 and addresses several limitations and findings of that research. In contrast to Halliwell, Heaney and Sawicki the current study finds the three factor model provides significantly improved explanatory power over the CAPM, and evidence that the BM factor plays a role in asset pricing.
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Background Relatively little international work has examined whether mental health resource allocation matches need. This study aimed to determine whether adult mental health resources in Australia are being distributed equitably. Method Individual measures of need were extrapolated to Australian Areas, and Area-based proxies of need were considered. Particular attention was paid to the prevalence of mental health problems, since this is arguably the most objective measure of need. The extent to which these measures predicted public sector, private sector and total adult mental health expenditure at an Area level was examined. Results In the public sector, 41.6% of expenditure variation was explained by the prevalence of affective disorders, personality disorders, cognitive impairment and psychosis, as well as the Area's level of economic resources and State/Territory effects. In the private sector, 72.4% of expenditure variation was explained by service use and State/Territory effects (with an alternative model incorporating service use and State/Territory supply of private psychiatrists explaining 69.4% of expenditure variation). A relatively high proportion (58.7%) of total expenditure variation could be explained by service utilisation and State/Territory effects. Conclusions For services to be delivered equitably, the majority of variation in expenditure would have to be accounted for by appropriate measures of need. The best model for public sector expenditure included an appropriate measure of need but had relatively poor explanatory power. The models for private sector and total expenditure had greater explanatory power, but relied on less appropriate measures of need. It is concluded that mental health services in Australia are not yet being delivered equitably.
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O período de transição para a universidade constitui-se um desafio para os estudantes devido à quantidade e à diversidade de mudanças originadas por um novo contexto pessoal e social que exige o desenvolvimento de recursos adaptativos. A vulnerabilidade trazida por essa fase pode motivar o uso de álcool e outras drogas, sendo um padrão recorrente encontrado em universitários. O bem-estar subjetivo (BES) e a autoeficácia (AE) são exemplos de fatores de proteção capazes de influenciar os comportamentos e atitudes dos jovens diante de situações como o consumo de bebidas alcoólicas. Sendo assim, o objetivo geral deste estudo foi analisar a capacidade explicativa do bem-estar subjetivo e da autoeficácia sobre o consumo de álcool em universitários. A amostra pesquisada foi constituída por 405 estudantes universitários de cursos da área da saúde da região metropolitana de São Paulo, com uma idade média de 21,69 (DP= 5,49), sendo a maioria do sexo feminino (81,5%), cursando o primeiro ou o segundo semestre, tanto do período matutino quanto do noturno. A análise dos dados foi realizada utilizando-se o programa SPSS, versão 20.0 para Windows para a realização de cálculos descritivos e exploratórios: média, desvio-padrão, correlações, análise de regressão múltipla, análises de variância (ANOVA) e teste t de Student. Os resultados do estudo revelaram que os universitários apresentaram um baixo nível de bem-estar subjetivo, autoeficácia acima da média e baixo consumo de álcool, sendo classificados na sua maioria como abstinentes. Foram observados indícios de que o bem-estar subjetivo e a autoeficácia predizem, ainda que de forma limitada, o consumo de álcool, destacando-se com maior capacidade preditiva os afetos negativos, a autoeficácia em ações pró-ativas e a autoeficácia em interação social. Além disso, a análise de correlação (r de Pearson) revelou que BES e AE guardam relação entre si, apresentando índices positivos e significativos. Também foram verificadas correlações significativas e negativas entre o consumo de álcool, a autoeficácia total e seus fatores, assim como correlações significativas e positivas entre o consumo de álcool e afetos negativos. Adicionalmente, é possível concluir que, no grupo estudado, dentre os jovens que consumiram álcool, estudantes do sexo masculino demonstraram um consumo maior da bebida do que as mulheres.
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A resiliência é um construto que remete à habilidade do ser humano de ter êxito frente às adversidades da vida, superá-las e inclusive, ser fortalecido ou transformado por elas. Campos de investigações da psicologia, como Psicologia da Saúde, Psicologia Positiva e Comportamento Organizacional Positivo, têm considerado a resiliência como uma importante via para a compreensão dos aspectos positivos e saudáveis dos indivíduos. Este trabalho pretendeu ampliar o conhecimento acerca da resiliência e suas relações com outros construtos no contexto organizacional. Para isto, definiu-se como objetivo geral deste estudo verificar a capacidade preditiva do conflito intragrupal (tarefa e relacionamento), do suporte social no trabalho (emocional, informacional e instrumental) e do autoconceito profissional (saúde, realização, autoconfiança e competência) sobre a resiliência (adaptação ou aceitação positiva de mudanças, espiritualidade, resignação diante da vida, competência pessoal e persistência diante das dificuldades) de policiais militares. Participaram do estudo 133 policiais militares de um batalhão do interior do estado de São Paulo, prevalecendo indivíduos do sexo masculino (97,7%), com idade média de 30 anos (DP= 5,7). Para a medida das variáveis foram utilizadas as seguintes escalas validadas: Escala de Avaliação de Resiliência reduzida, Escala de Conflitos Intragrupais, Escala de Percepção de Suporte Social no Trabalho e a Escala de Autoconceito Profissional. Os dados foram submetidos a cálculos descritivos e a análises de regressão linear múltipla padrão. Os resultados indicaram que o modelo que reunia as variáveis antecedentes (conflito intragrupal, suporte social no trabalho e autoconceito profissional) explicou significativamente a variância das dimensões da resiliência: 30% da persistência diante das dificuldades, 29% da adaptação ou aceitação positiva de mudanças, 28% da competência pessoal e 11% da espiritualidade. As variáveis que tiveram impacto estatisticamente importante sobre a persistência diante das dificuldades foram o suporte emocional no trabalho, cuja direção da predição foi inversa, e autoconfiança, cuja direção da predição foi direta. A adaptação ou aceitação positiva de mudanças teve como preditor inverso a variável saúde e como preditor direto a autoconfiança. A competência pessoal teve impacto significativo da variável autoconfiança, que se mostrou um preditor direto. A espiritualidade, por sua vez, teve um único preditor significante, a variável realização, cuja direção da predição foi direta. Os resultados sugerem que dentre as variáveis antecedentes, o autoconceito profissional evidenciou maior poder de explicação da variância da resiliência. À luz da literatura da área foram discutidos estes achados. Por fim, foram apresentadas as limitações e a proposta de uma agenda de pesquisa que contribua para confirmação e ampliação dos resultados desta investigação.
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This study seeks to explain the leverage in UK stock returns by reference to the return volatility, leverage and size characteristics of UK companies. A leverage effect is found that is stronger for smaller companies and has greater explanatory power over the returns of smaller companies. The properties of a theoretical model that predicts that companies with higher leverage ratios will experience greater leverage effects are explored. On examining leverage ratio data, it is found that there is a propensity for smaller companies to have higher leverage ratios. The transmission of volatility shocks between the companies is also examined and it is found that the volatility of larger firm returns is important in determining both the volatility and returns of smaller firms, but not the reverse. Moreover, it is found that where volatility spillovers are important, they improve out-of-sample volatility forecasts. © 2005 Taylor & Francis Group Ltd.
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The Aspect Hypothesis (AH) claims that the association of any verb category (lexical aspect) with any grammatical aspect (perfective or imperfective) constitutes the endpoint of acquisition. The present book evaluates the explanatory power of the Aspect Hypothesis for the acquisition of French past tenses, which constitutes a serious stumbling block for foreign learners, even at the highest levels of proficiency. The present research applies the Aspect Hypothesis to the production of 61 Anglophone 'advanced learners' in a tutored environment. In so doing, it tests concurrent explanations, including the influence of the input, the influence of chunking, and the hypothesis of cyclic development. It discusses the cotextual and contextual factors that still provoke «non-native glitches» at the final stage of the Aspect Hypothesis. The book shows that the AH fails to account for the complex phenomenon of past tense development, as it adopts a local and linear approach.
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Translation norms are understood as internalized behavioural constraints which embody the values shared by a community. In the two main contributions it is argued that all decisions in the translation process are primarily governed by norms. The explanatory power of a norm-based theory of translation is then critically reflected upon in the debates and the responses.
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The purpose of this thesis is to shed more light in the FX market microstructure by examining the determinants of bid-ask spread for three currencies pairs, the US dollar/Japanese yen, the British pound/US dollar and the Euro/US dollar in different time zones. I examine the commonality in liquidity with the elaboration of FX market microstructure variables in financial centres across the world (New York, London, Tokyo) based on the quotes of three exchange rate currency pairs over a ten-year period. I use GARCH (1,1) specifications, ICSS algorithm, and vector autoregression analysis to examine the effect of trading activity, exchange rate volatility and inventory holding costs on both quoted and relative spreads. ICSS algorithm results show that intraday spread series are much less volatile compared to the intraday exchange rate series as the number of change points obtained from ICSS algorithm is considerably lower. GARCH (1,1) estimation results of daily and intraday bid-ask spreads, show that the explanatory variables work better when I use higher frequency data (intraday results) however, their explanatory power is significantly lower compared to the results based on the daily sample. This suggests that although daily spreads and intraday spreads have some common determinants there are other factors that determine the behaviour of spreads at high frequencies. VAR results show that there are some differences in the behaviour of the variables at high frequencies compared to the results from the daily sample. A shock in the number of quote revisions has more effect on the spread when short term trading intervals are considered (intra-day) compared to its own shocks. When longer trading intervals are considered (daily) then the shocks in the spread have more effect on the future spread. In other words, trading activity is more informative about the future spread when intra-day trading is considered while past spread is more informative about the future spread when daily trading is considered
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This thesis sets out to investigate the role of cohesion in the organisation and processing of three text types in English and Arabic. In other words, it attempts to shed some light on the descriptive and explanatory power of cohesion in different text typologies. To this effect, three text types, namely, literary fictional narrative, newspaper editorial and science were analysed to ascertain the intra- and inter-sentential trends in textual cohesion characteristic of each text type in each language. In addition, two small scale experiments which aimed at exploring the facilitatory effect of one cohesive device (i.e. lexical repetition) on the comprehension of three English text types by Arab learners were carried out. The first experiment examined this effect in an English science text; the second covered three English text types, i.e. fictional narrative, culturally-oriented and science. Some interesting and significant results have emerged from the textual analysis and the pilot studies. Most importantly, each text type tends to utilize the cohesive trends that are compatible with its readership, reader knowledge, reading style and pedagogical purpose. Whereas fictional narratives largely cohere through pronominal co-reference, editorials and science texts derive much cohesion from lexical repetition. As for cross-language differences English opts for economy in the use of cohesive devices, while Arabic largely coheres through the redundant effect created by the high frequency of most of those devices. Thus, cohesion is proved to be a variable rather than a homogeneous phenomenon which is dictated by text type among other factors. The results of the experiments suggest that lexical repetition does facilitate the comprehension of English texts by Arab learners. Fictional narratives are found to be easier to process and understand than expository texts. Consequently, cohesion can assist in the processing of text as it can in its creation.
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This thesis describes research on End-User Computing (EUC) in small business in an environment where no Information System (IS) support and expertise are available. The research aims to identify the factors that contribute to EUC Sophistication and understand the extent small firms are capable of developing their own applications. The intention is to assist small firms to adopt EUC, encourage better utilisation of their IT resources and gain the benefits associated with computerisation. The factors examined are derived inductively from previous studies where a model is developed to map these factors with the degree of sophistication associated with IT and EUC. This study attempts to combine the predictive power of quantitative research through surveys with the explanatory power of qualitative research through action-oriented case study. Following critical examination of the literature, a survey of IT Adoption and EUC was conducted. Instruments were then developed to measure EUC and IT Sophistication indexes based on sophistication constructs adapted from previous studies using data from the survey. This is followed by an in-depth action case study involving two small firms to investigate the EUC phenomenon in its real life context. The accumulated findings from these mixed research strategies are used to form the final model of EUC Sophistication in small business. Results of the study suggest both EUC Sophistication and the Presence of EUC in small business are affected by Management Support and Behaviour towards EUC. Additionally EUC Sophistication is also affected by the presence of an EUC Champion. Results are also consistent with respect to the independence between IT Sophistication and EUC Sophistication. The main research contributions include an accumulated knowledge of EUC in small business, the Model of EUC Sophistication, an instrument to measure EUC Sophistication Index for small firms, and a contribution to research methods in IS.
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Following Andersen's (1986, 1991) study of untutored anglophone learners of Spanish, aspectual features have been at the centre of hypotheses on the development of past verbal morphology in language acquisition. The Primacy of Aspect Hypothesis claims that the association of any verb category (Aktionsart) with any aspect (perfective or imperfective) constitutes the endpoint of acquisition. However, its predictions rely on the observation of a limited number of untutored learners at the early stages of their acquisition, and have yet to be confirmed in other settings. The aim of the present thesis is to evaluate the explanatory power of the PAH in respect of the acquisition of French past tenses, an aspect of the language which constitutes a serious stumbling block for foreign learners, even those at the highest levels of proficiency (Coppieters 1987). The present research applies the PAH to the production of 61 anglophone 'advanced learners' (as defined in Bartning 1997) in a tutored environment. In so doing, it tests concurrent explanations, including the influence of the input, the influence of chunking, and the hypothesis of cyclic development. Finally, it discusses the cotextual and contextual factors that still provoke what Anderson (1991) terms "non-native glitches" at the final stage, as predicted by the PAH. The first part of the thesis provides the theoretical background to the corpus analysis. It opens with a diachronic presentation of the French past tense system focusing on present areas of competition and developments that emphasize the complexity of the system to be acquired. The concepts of time, grammatical aspect and lexical aspect (Aktionsart) are introduced and discussed in the second chapter, and a distinctive formal representation of the French past tenses is offered in the third chapter. The second part of the thesis is devoted to a corpus analysis. The data gathering procedures and the choice of tasks (oral and written film narratives based on Modern Times, cloze tests and acceptability judgement tests) are described and justified in the research methodology chapter. The research design was shaped by previous studies and consequently allows comparison with these. The second chapter is devoted to the narratives analysis and the third to the grammatical tasks. This section closes with a summary of discoveries and a comparison with previous results. The conclusion addresses the initial research questions in the light of both theory and practice. It shows that the PAH fails to account for the complex phenomenon of past tense development in the acquisitional settings under study, as it adopts a local (the verb phrase) and linear (steady progression towards native usage) approach. It is thus suggested that past tense acquisition rather follows a pendular development as learners reformulate their learning hypotheses and become increasingly able to shift from local to global cues and so to integrate the influence of cotext and context in their tense choice.
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We have attempted to bring together two areas which are challenging for both IS research and practice: forms of coordination and management of knowledge in the context of global, virtual software development projects. We developed a more comprehensive, knowledge-based model of how coordination can be achieved, and\illustrated the heuristic and explanatory power of the model when applied to global software projects experiencing different degrees of success. We first reviewed the literature on coordination and determined what is known about coordination of knowledge in global software projects. From this we developed a new, distinctive knowledge-based model of coordination, which was then employed to analyze two case studies of global software projects, at SAP and Baan, to illustrate the utility of the model.