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Determinantes da adesão a tratados de patentes, 1970-2000: a Convenção de Paris e o Tratado de Cooperação de patentes / The determinants of the accession of the accession of patent treaties, 1970-2000: the Paris Convention and Patents Cooperation TreatyPereira Neto, Manoel Galdino 30 September 2011 (has links)
Neste trabalho investigamos os determinantes da adesão de países a dois tratados internacionais de patentes: A Convenção de Paris e o Tratado de Cooperação de Patentes (TCP). Por meio de um modelo hierárquico Bayesiano, apresentamos evidências de que fatores domésticos são importantes para predizer adesão aos tratados estudados. Porém, quais fatores são importantes dependem do tipo de tratado. Para o TCP, que é um tratado que visa reduzir custos de transação, a legislação doméstica de patentes não é relevante. Para a Convenção de Paris, que limita as opções de política na área de patente, a legislação doméstica é fator relevante. Nós mostramos também que os ganhos diretos de participar dos tratados, medido pelo número de patentes no exterior, é uma variável importante e positivamente associada à probabilidade de adesão a ambos os acordos. Apresentamos ainda evidências de que variáveis sistêmicas são importantes e que as mudanças no sistema internacional nos últimos 30 anos são fatores importantes para explicar a adesão. / In this paper we investigate the determinants of the accession of two international patent treaties: the Paris Convention and Patent Cooperation Treaty (PCT). Through a Bayesian hierarchical model, we present evidence that domestic factors are important in predicting accession to the treaties studied. However, what factors are important depends on the type of treaty. For TCP, which is a treaty aimed at reducing transaction costs, the domestic law of patents is not important. For the Paris Convention, which limits the options in the area of patent policy, domestic law is a relevant factor. We also show that the direct gains from participating in treaties, as measured by the number of patents abroad, is an important variable and positively associated with the likelihood of ratification to both agreements. We also present evidence that systemic variables are important and that changes in the international system over the past 30 years are important factors to explain the membership to the treaties.
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A Bayesian Approach to Detect the Onset of Activity Limitation Among Adults in NHISBai, Yan 06 May 2005 (has links)
Data from the 1995 National Health Interview Survey (NHIS) indicate that, due to chronic conditions, the onset of activity limitation typically occurs between age 40-70 years (i.e., the proportion of young adults with activity limitation is small and roughly constant with age and then it starts to change, roughly increasing). We use a Bayesian hierarchical model to detect the change point of a positive activity limitation status (ALS) across twelve domains based on race, gender, and education. We have two types of data: weighted and unweighted. We obtain weighted binomial counts using a regression analysis with the sample weights. Given the proportion of individuals in the population with positive ALS, we assume that the number of individuals with positive ALS at each age group has a binomial probability mass function. The proportions across age are different, and have the same beta distribution up to the change point (unknown), and the proportions after the change point have a different beta distribution. We consider two different analyses. The first considers each domain individually in its own model and the second considers the twelve domains simultaneously in a single model to“borrow strength" as in small area estimation. It is reasonable to assume that each domain has its own onset.In the first analysis, we use the Gibbs sampler to fit the model, and a computation of the marginal likelihoods, using an output analysis from the Gibbs sampler, provides the posterior distribution of the change point. We note that a reversible jump sampler fails in this analysis because it tends to get stuck either age 40 or age 70. In the second analysis, we use the Gibbs sampler to fit only the joint posterior distribution of the twelve change points. This is a difficult problem because the joint density requires the numerical computation of a triple integral at each iteration. The other parameters of the process are obtained using data augmentation by a Metropolis sampler and a Rao-Blackwellization. We found that overall the age of onset is about 50 to 60 years.
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THE EFFECTS OF MOUNTAINTOP REMOVAL MINING AND VALLEY FILLS ON STREAM SALAMANDER COMMUNITIESMuncy, Brenee' Lynn 01 January 2014 (has links)
Mountaintop removal mining and valley filling (MTR/VF) is a common form of land conversion in Central Appalachia and threatens the integrity of stream ecosystems. We investigated the effects of MTR/VF on stream salamander occupancy probabilities and community structure by conducting area constrained active searches for stream salamanders within intermittent streams located in mature forest (i.e., control) and those impacted by MTR/VF. During March to June of 2013, we detected five stream salamander species (Desmognathus fuscus, D. monticol, Eurycea cirrigera, Pseudotriton ruber, and Gyrinophilus porphyriticus) and found that the probability of occupancy was greatly reduced in MTR/VF streams compared to control streams. Additionally, the salamander community was greatly reduced in MTR/VF streams; the mean species richness estimate for MTR/VF streams was 2.09 (± 1.30 SD), whereas richness was 4.83 (± 0.58 SD) for control streams. Numerous mechanisms may be responsible for decreased occupancy and diminished salamander communities at MTR/VF streams, although water chemistry of streams may be a particularly important mechanism. Indeed, we detected elevated levels of specific conductivity, pH, total organic carbon, and dissolved ions in MTR/VF streams. Our results indicate that salamander communities, with other invertebrates, fish, and other aquatic and/or semi-aquatic animals, are susceptible to MTR/VF mining practices.
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Determinantes da adesão a tratados de patentes, 1970-2000: a Convenção de Paris e o Tratado de Cooperação de patentes / The determinants of the accession of the accession of patent treaties, 1970-2000: the Paris Convention and Patents Cooperation TreatyManoel Galdino Pereira Neto 30 September 2011 (has links)
Neste trabalho investigamos os determinantes da adesão de países a dois tratados internacionais de patentes: A Convenção de Paris e o Tratado de Cooperação de Patentes (TCP). Por meio de um modelo hierárquico Bayesiano, apresentamos evidências de que fatores domésticos são importantes para predizer adesão aos tratados estudados. Porém, quais fatores são importantes dependem do tipo de tratado. Para o TCP, que é um tratado que visa reduzir custos de transação, a legislação doméstica de patentes não é relevante. Para a Convenção de Paris, que limita as opções de política na área de patente, a legislação doméstica é fator relevante. Nós mostramos também que os ganhos diretos de participar dos tratados, medido pelo número de patentes no exterior, é uma variável importante e positivamente associada à probabilidade de adesão a ambos os acordos. Apresentamos ainda evidências de que variáveis sistêmicas são importantes e que as mudanças no sistema internacional nos últimos 30 anos são fatores importantes para explicar a adesão. / In this paper we investigate the determinants of the accession of two international patent treaties: the Paris Convention and Patent Cooperation Treaty (PCT). Through a Bayesian hierarchical model, we present evidence that domestic factors are important in predicting accession to the treaties studied. However, what factors are important depends on the type of treaty. For TCP, which is a treaty aimed at reducing transaction costs, the domestic law of patents is not important. For the Paris Convention, which limits the options in the area of patent policy, domestic law is a relevant factor. We also show that the direct gains from participating in treaties, as measured by the number of patents abroad, is an important variable and positively associated with the likelihood of ratification to both agreements. We also present evidence that systemic variables are important and that changes in the international system over the past 30 years are important factors to explain the membership to the treaties.
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Non-Intrusive Load Monitoring to Assess Retrofitting Work / Non-intrusive load monitoring för utvärderingen av renoveringsarbetens effektivitetenZucchet, Julien January 2022 (has links)
Non-intrusive load monitoring (NILM) refers to a set of statistical methods for inferring information about a household from its electricity load curve, without adding any additional sensor. The aim of this master thesis is to adapt NILM techniques for the assessment of the efficiency of retrofitting work to provide a first version of a retrofitting assessment tool. Two models are developed: a model corresponding to a constrained optimization problem, and a hierarchical Bayesian mixture model. These models are tested on a set of houses that have electric heating (which are the main target of retrofitting work). These models offer a satisfactory accuracy retrofitting assessment for about half of the houses. / Non-intrusive load monitoring (NILM) består av en uppsättning statistiska metoder för att härleda information om ett hushåll från belastningskurvan i bostaden, utan att lägga till ytterligare sensorer. Syftet med detta examensarbete är att anpassa NILM-teknikerna till utvärdering av energieffektivitet i energibyggnader och för att föreslå en första version av ett verktyg för utvärdering av effektiviteten i renoveringsarbeten. Två modeller föreslås: en modell som motsvarar ett begränsat optimeringsproblem och en hierarkisk Bayesiansk blandningsmodell. Modellerna testas på en uppsättning med elvärme (som är huvudmålet för renoveringsarbeten). De utvecklade modellerna gör det möjligt att upprå en tillfredsställande noggrannhet vid utvärderingen av arbeten för ungefär hälften av husen.
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TESTING FOR DIFFERENTIALLY EXPRESSED GENES AND KEY BIOLOGICAL CATEGORIES IN DNA MICROARRAY ANALYSISSARTOR, MAUREEN A. January 2007 (has links)
No description available.
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A Hierarchical Bayesian Model for the Unmixing Analysis of Compositional Data subject to Unit-sum ConstraintsYu, Shiyong 15 May 2015 (has links)
Modeling of compositional data is emerging as an active area in statistics. It is assumed that compositional data represent the convex linear mixing of definite numbers of independent sources usually referred to as end members. A generic problem in practice is to appropriately separate the end members and quantify their fractions from compositional data subject to nonnegative and unit-sum constraints. A number of methods essentially related to polytope expansion have been proposed. However, these deterministic methods have some potential problems.
In this study, a hierarchical Bayesian model was formulated, and the algorithms were coded in MATLABÒ. A test run using both a synthetic and real-word dataset yields scientifically sound and mathematically optimal outputs broadly consistent with other non-Bayesian methods. Also, the sensitivity of this model to the choice of different priors and structure of the covariance matrix of error were discussed.
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Croissance de l'albacore (Thunnus albacares) de l'Océan Indien : de la modélisation statistique à la modélisation bio-énergétique / Growth of Indian Ocean yellowfin tuna (Thunnus albacares) : statistical modelling to bioenergetic modellingDortel, Emmanuelle 11 June 2014 (has links)
Depuis le début des années 1960, la croissance de l'albacore fait l'objet d'une attention particulière tant dans le domaine de la recherche que pour la gestion des pêcheries. Dans l'océan Indien, la gestion du stock d'albacores, sous la juridiction le Commission Thonière de l'Océan Indien (CTOI), souffre de nombreuses incertitudes associées à la courbe de croissance actuellement considérée. En particulier, des lacunes subsistent dans notre connaissance des processus biologiques et écologiques élémentaires régulant la croissance. Leur connaissance est pourtant fondamentale pour comprendre la productivité des stocks et leur capacité de résistance à la pression de pêche et aux changements océanographiques en cours. À travers la modélisation, cette étude se propose d'améliorer les connaissances actuelles sur la croissance de la population d'albacore de l'océan Indien et de renforcer ainsi les avis scientifiques sur l'état du stock. Alors que la plupart des études sur la croissance de l'albacore s'appuient sur une seule source de données, nous avons mis en œuvre un modèle hiérarchique Bayésien qui exploite diverses sources d'informations sur la croissance, i.e. des estimations d'âge obtenues par otolithométrie, des analyses de progressions modales et les taux de croissance individuels issus du marquage-recapture, et intègre explicitement des connaissances d'experts et les incertitudes associées à chaque source de données ainsi qu'au processus de modélisation. En particulier, le modèle de croissance a été couplé un à modèle d'erreurs dans les estimations d'âge par otolithométrie apportant une amélioration significative des estimations d'âge et des paramètres de croissance en résultant et permettant une meilleure évaluation de la fiabilité des estimations. Les courbes de croissances obtenues constituent une avancée majeure dans la représentation du patron de croissance actuellement utilisé dans les évaluations de stock d'albacore. Elles démontrent que l'albacore présente une croissance en phases, caractérisée par une forte accélération en fin de phase juvénile. Cependant, elles n'apportent aucune information sur les mécanismes biologiques et écologiques à l'origine de ces phases de croissance. Afin de mieux comprendre les facteurs impliqués dans l'accélération de la croissance, nous avons mis en œuvre un modèle bio-énergétique s'appuyant sur les principes de la théorie des bilans dynamiques d'énergie (DEB). Deux hypothèses apparaissant comme les plus pertinentes ont été testées : (i) une faible disponibilité alimentaire liée à une forte compétition inter et intra-spécifique chez les jeunes albacores formant des bancs et (ii) un changement dans le régime alimentaire des adultes s'accompagnant de la consommation de proies plus énergétiques. Il apparait que ces deux hypothèses sont susceptibles d'expliquer, au moins partiellement, l'accélération de la croissance. / Since the early 1960s, the growth of yellowfin has been enjoyed a particular attention both in the research field and for fisheries management. In the Indian Ocean, the management of yellowfin stock, under the jurisdiction of the Indian Ocean Tuna Commission (IOTC), suffers from much uncertainty associated with the growth curve currently considered. In particular, there remain gaps in our knowledge of basic biological and ecological processes regulating growth. Their knowledge is however vital for understanding the stocks productivity and their resilience abilities to fishing pressure and oceanographic changes underway.Through modelling, this study aims to improve current knowledge on the growth of yellowfin population of the Indian Ocean and thus strengthen the scientific advice on the stock status. Whilst most studies on yellowfin growth only rely on one data source, we implemented a hierarchical Bayesian model that exploits various information sources on growth, i.e. direct age estimates obtained through otolith readings, analyzes of modal progressions and individual growth rates derived from mark-recapture experiments, and takes explicitely into account the expert knowledge and the errors associated with each dataset and the growth modelling process. In particular, the growth model was coupled with an ageing error model from repeated otolith readings which significantly improves the age estimates as well as the resulting growth estimates and allows a better assessment of the estimates reliability. The growth curves obtained constitute a major improvement of the growth pattern currently used in the yellowfin stock assessment. They demonstrates that yellowfin exhibits a two-stanzas growth, characterized by a sharp acceleration at the end of juvenile stage. However, they do not provide information on the biological and ecological mechanisms that lie behind the growth acceleration.For a better understanding of factors involved in the acceleration of growth, we implemented a bioenergetic model relying on the principles of Dynamic Energy Budget theory (DEB). Two major assumptions were investigated : (i) a low food availability during juvenile stage in relation with high intra and inter-specific competition and (ii) changes in food diet characterized by the consumption of more energetic prey in older yellowfin. It appears that these two assumption may partially explain the growth acceleration.
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Bayesian Models for the Analyzes of Noisy Responses From Small Areas: An Application to Poverty EstimationManandhar, Binod 26 April 2017 (has links)
We implement techniques of small area estimation (SAE) to study consumption, a welfare indicator, which is used to assess poverty in the 2003-2004 Nepal Living Standards Survey (NLSS-II) and the 2001 census. NLSS-II has detailed information of consumption, but it can give estimates only at stratum level or higher. While population variables are available for all households in the census, they do not include the information on consumption; the survey has the `population' variables nonetheless. We combine these two sets of data to provide estimates of poverty indicators (incidence, gap and severity) for small areas (wards, village development committees and districts). Consumption is the aggregate of all food and all non-food items consumed. In the welfare survey the responders are asked to recall all information about consumptions throughout the reference year. Therefore, such data are likely to be noisy, possibly due to response errors or recalling errors. The consumption variable is continuous and positively skewed, so a statistician might use a logarithmic transformation, which can reduce skewness and help meet the normality assumption required for model building. However, it could be problematic since back transformation may produce inaccurate estimates and there are difficulties in interpretations. Without using the logarithmic transformation, we develop hierarchical Bayesian models to link the survey to the census. In our models for consumption, we incorporate the `population' variables as covariates. First, we assume that consumption is noiseless, and it is modeled using three scenarios: the exponential distribution, the gamma distribution and the generalized gamma distribution. Second, we assume that consumption is noisy, and we fit the generalized beta distribution of the second kind (GB2) to consumption. We consider three more scenarios of GB2: a mixture of exponential and gamma distributions, a mixture of two gamma distributions, and a mixture of two generalized gamma distributions. We note that there are difficulties in fitting the models for noisy responses because these models have non-identifiable parameters. For each scenario, after fitting two hierarchical Bayesian models (with and without area effects), we show how to select the most plausible model and we perform a Bayesian data analysis on Nepal's poverty data. We show how to predict the poverty indicators for all wards, village development committees and districts of Nepal (a big data problem) by combining the survey data with the census. This is a computationally intensive problem because Nepal has about four million households with about four thousand households in the survey and there is no record linkage between households in the survey and the census. Finally, we perform empirical studies to assess the quality of our survey-census procedure.
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Tree growth and mortality and implications for restoration and carbon sequestration in Australian subtropical semi-arid forests and woodlandsJohn Dwyer Unknown Date (has links)
Many researchers have highlighted the dire prospects for biodiversity in fragmented agricultural landscapes and stressed the need for increasing the area of, and connectivity between, natural ecosystems. Some have advocated the use of naturally regenerating forest ecosystems for sequestering atmospheric carbon, with opportunities for dual restoration and carbon benefits. However, no studies have explicitly explored the feasibility of obtaining such dual benefits from a regenerating woody ecosystem. This thesis aims to provide a detailed assessment of the restoration and carbon potential of Brigalow regrowth, an extensive naturally regenerating ecosystem throughout the pastoral regions of north eastern Australia. It combines observational, experimental and modelling techniques to describe the agricultural legacy of pastoral development, identify constraints to restoration and explore methods to remove these constraints. A review of existing ecological knowledge of Brigalow ecosystems is provided in chapter 3, along with discussion of policy and socio-economic issues that are likely to influence how and to what extent regrowth is utilised for restoration and carbon purposes in the Brigalow Belt. The review found restoring regrowth is likely to have benefits for a wide range of native flora and fauna, including the endangered bridled nailtail wallaby. Knowledge gaps exist relating to the landscape ecology of Brigalow regrowth and the impacts of management and climate change on carbon and restoration potential. Also, a conflict exists between short-term carbon sequestration and long-term restoration goals. Regional demand for high biomass regrowth as a carbon offset is likely to be high but ambiguities in carbon policy threaten to diminish the use of natural regrowth for reforestation projects. A large cross-sectional study of regrowth is presented in chapter 4. Data were analysed using multi-level / hierarchical Bayesian models (HBMs). Firstly, we found that repeated attempts at clearing Brigalow regrowth increases stem densities and densities remain high over the long term, particularly in high rainfall areas and on clay soils with deep gilgais. Secondly, higher density stands have slower biomass accumulation and structural development in the long term. Spatial extrapolations of the HBMs indicated that the central and eastern parts of the study region are most environmentally suitability for biomass accumulation, however these may not correspond to the areas that historically supported the highest biomass Brigalow forests. We conclude that carbon and restoration goals are largely congruent within regions of similar climate. At the regional scale however, spatial prioritisation of restoration and carbon projects may only be aligned in areas with higher carbon potential. Given the importance of stem density in determining restoration and carbon potential, an experimental thinning trial was established in dense Brigalow regrowth in southern Queensland (chapter 5). Four treatments were applied in a randomised block design and growth and mortality of a subset of stems was monitored for two years. Data were analysed using mixed-effects models and HBMs and the latter were subsequently used to parameterise an individual-based simulation model of stand structural development and biomass accumulation over 50 years. The main findings of this study were that growth and mortality of stems is influenced by the amount of space available to each stem (a neighbourhood effect) and that thinning accelerates structural development and increases woody species diversity. The examination of neighbourhood effects is taken further by considering drought-related mortality in a Eucalyptus savanna ecosystem (chapter 6). For this work a multi-faceted approach was employed including spatial pattern analyses and statistical models of stem survival to test three competing hypotheses relating to neighbourhood effects on drought related tree mortality. The main finding of this study was that neighbour density and microsite effects both influence drought-related mortality and the observed patterns can readily be explained by an interaction between these two factors. As a whole, this thesis contributes the following scientific insights: (1) restoration and carbon goals may be aligned for naturally regenerating woody ecosystems, but the degree of goal congruence will vary across the landscape in question, (2) while some woody ecosystems retain an excellent capacity to regenerate naturally, the agricultural legacy may still have long term effects on restoration and carbon potential, (3) neighbourhood effects that operate at the stem scale strongly influence dynamics at the ecosystem scale.
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