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‣ Redução no vício da distribuição da deviance para dados de contagem.; Bias reduction in the distribution of the deviance for count data.

Viola, Denise Nunes
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/10/2001 Português
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Dados de contagem podem ser considerados, em geral, como provenientes de uma distribuição de Poisson. Neste contexto, a análise de tais dados apresenta certas dificuldades, pois não segue algumas pressuposições básicas para o ajuste de um modelo matemático. Desse modo, algumas transformações são sugeridas, mas nem sempre bons resultados são obtidos. No enfoque de Modelos Lineares Generalizados, a estatística que mede a qualidade do ajuste do modelo para os dados é chamada deviance. Porém, a distribuição da deviance é, em geral, desconhecida. No entanto, para dados com distribuição de Poisson, pode-se mostrar que a distribuição da deviance se aproxima de uma distribuição ?2, mas tal aproximação não é boa para tamanhos pequenos de amostra. Para melhorar essa aproximação, alguns fatores de correção para os dados são sugeridos, mas os resultados obtidos ainda não são satisfatórios. Assim, o objetivo deste trabalho é propor um novo fator de correção para os dados seguindo uma distribuição de Poisson, de modo a se obter uma melhora na distribuição da deviance para qualquer tamanho de amostra. Para isto, será adicionada uma constante à variável resposta e, através do valor esperado da deviance...

‣ New distribution data on spanish autochthonous species of freshwater fish

Perea, Silvia; Garzón, Paloma; González, José Luis; Almada, Vítor Carvalho; Pereira, Ana Martins; Doadrio, Ignacio
Fonte: Museo Nacional de Ciencias Naturales Publicador: Museo Nacional de Ciencias Naturales
Tipo: Artigo de Revista Científica
Publicado em //2011 Português
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Over the last two years (2008-2010) we performed a monitoring project to update the Spanish freshwater fish fauna. We have collected in 785 sampling localities homogeneously distributed throughout Spain each year. We find as the most important result of this study the occurrence of several species that constitute new records for some rivers or basins in Spain: Lampetra planeri, Petromyzon marinus, Barbus haasi, Iberochondrostoma lemmingii, Squalius alburnoides, Squalius carolitertii, Squalius malacitanus, Cobitis calderoni, Cobitis paludica, and Salaria fluviatilis. Finally we corroborate the existence of Barbatula barbatula in the Duero basin and the assignation of the northeastern populations of this genus to B. quignardi.

‣ Spatial Distribution of the Rice Stink Bug (Heteroptera: Pentatomidae) in Florida Rice

Foster, R. E.; Cherry, R. H.; Jones, D. B.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
Português
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Rice fields in southern Florida were sampled for rice stink bug, Oebalus pugnax (F.), to determine the spatial distribution. Data from 20 fields showed that the insects were aggregated in fields in the nymphal stage, the adult stage, and the combined total of the two stages based on Taylor’s power law. Data indicate that samples taken from the ends of the field accurately predict the overall field mean. Adults were the most common stage caught during the first rice crop, and nymphs were the most common stage caught during the ratoon crop.

‣ Big Bad Banks? The Impact of U.S. Branch Deregulation on Income Distribution

Beck, Thorsten; Levine, Ross; Levkov, Alexey
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Português
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Policymakers and economists disagree about the impact of bank regulations on the distribution of income. Exploiting cross-state and cross-time variation, the authors test whether liberalizing restrictions on intra-state branching in the United States intensified, ameliorated, or had no effect on income distribution. The analysis finds that branch deregulation lowered income inequality by affecting labor market conditions, not by boosting the business income of the poor, nor by enhancing educational attainment. Reductions in the earnings gap between men and women and between skilled and unskilled workers account for the bulk of the explained drop in income inequality.

‣ Can We Discern the Effect of Globalization on Income Distribution? Evidence from Household Surveys

Milanovic, Branko
Fonte: Published by Oxford University Press on behalf of the World Bank Publicador: Published by Oxford University Press on behalf of the World Bank
Tipo: Artigo de Revista Científica
Português
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New data derived directly from household surveys are used to examine the effects of globalization on income distribution in poor and rich countries. The article looks at the impact of openness and of direct foreign investment on relative income shares across the entire income distribution. It finds strong evidence that at low average income levels, the income share of the poor is smaller in countries that are more open to trade. As national income levels rise, the incomes of the poor and the middle class rise relative to the income of the rich. The article explains why using the trade to gross domestic product (GDP) ratio in purchasing power parity terms, as favored by some analysts, is inappropriate in studies of the effect of trade on income distribution.

‣ Survey Compliance and the Distribution of Income

Mistiaen, Johan A.; Ravallion, Martin
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Português
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While it is improbable that households with different incomes are equally likely to participate in sample surveys, the lack of data for nonrespondents has hindered efforts to correct for the bias in measures of poverty and inequality. The authors demonstrate how the latent income effect on survey compliance can be estimated using readily available data on response rates across geographic areas. An application using the Current Population Survey for the United States indicates that compliance falls as income rises. Correcting for selective compliance appreciably increases mean income and inequality, but has only a small impact on poverty incidence up to commonly used poverty lines in the United States.

‣ Economic Growth, Inequality, and Poverty : Findings from a New Data Set

Adams, Richard H., Jr.
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Português
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The author uses new data from 50 developing countries and 101 intervals to examine the impact of economic growth on poverty and inequality. He finds that growth represents an important means for reducing poverty in the developing world. When economic growth is measured by survey mean income (consumption), there is a strong, statistical link between growth and poverty reduction. When economic growth is measured by GDP per capita, the statistical relationship between growth and poverty reduction is still present, albeit not quite as strong. Economic growth reduces poverty because growth has little impact on income inequality. In the data set income inequality rises on average less than 1.0 percent a year. Since income distributions are relatively stable over time, economic growth tends to raise incomes for all members of society, including the poor. When growth is measured by survey mean income (consumption), the elasticity of poverty with respect to growth is -2.59. In other words, on average, a 10 percentage point increase in economic growth (measured by survey mean income) will produce a 25.9 percent decrease in the proportion of people living in poverty ($1 a person a day).

‣ Technical Assessment of Open Data Platforms for National Statistical Organisations

World Bank Group
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Português
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The term quot;open dataquot; is generally understood to be data that are made available to the public free of charge, without registration or restrictive licenses, for any purpose whatsoever (including commercial purposes), in electronic, machine-readable formats that ensure data are easy to find, download and use. National Statistics Offices (NSOs) have the potential to play a pivotal role in the implementation of open data initiatives. As producers and curators of data, the objective of making high quality data more accessible and usable is consistent with their guiding principles. NSOs indicate, in research conducted in support of this report, that one of the difficulties they encounter is that the technology they use to publish - or electronically distribute - data for public use is not compatible with open formats. They also indicate that common software packages used for open data portals do not accommodate the data formats and metadata they produce. Two key concerns related to data dissemination products are addresses: (1) Can such products designed primarily for NSOs satisfy requirements for an open data initiative?; and (2) Can such products designed primarily for open data satisfy the requirements of NSOs? Furthermore...

‣ Asset Distribution, Inequality, and Growth

Deininger, Klaus; Olinto, Pedro
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
Português
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With the recent resurgence of interest in equity, inequality, and growth, the possibility of a negative relationship between inequality and economic growth, has received renewed interest in the literature. Faced with the prospect that high levels of inequality may persist, and give rise to poverty traps, policymakers are paying more attention to the distributional implications of macroeconomic policies. Because high levels of inequality may hurt overall growth, policymakers are exploring measures to promote growth and equity at the same time. How the consequences of inequality are analyzed, along with the possible cures, depends partly on how inequality is measured. The authors use assets (land) rather than income - and a GMM estimator - to examine the robustness of the relationship between inequality and growth that has been observed in the cross-sectional literature, but has been drawn into question by recent studies using panel techniques. They find evidence that asset inequality - but not income inequality - has a relatively large negative impact on growth. They also find that a highly unequal distribution of assets reduces the effectiveness of educational interventions. This means that policymakers should be more concerned about households' access to assets...

‣ Decomposing World Income Distribution : Does the World Have a Middle Class?

Milanovic, Branko; Yitzhaki, Shlomo
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
Português
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Using national income and expenditure distribution data from 119 countries, the authors decompose total income inequality between the individuals in the world, by continent and by "region" (countries grouped by income level). They use a Gini decomposition that allows for an exact breakdown (without a residual term) of the overall Gini by recipients. Looking first at income inequality in income between countries is more important than inequality within countries. Africa, Latin America, and Western Europe and North America are quite homogeneous continent, with small differences between countries (so that most of the inequality on these continents is explained by inequality within countries). Next the authors divide the world into three groups: the rich G7 countries (and those with similar income levels), the less developed countries (those with per capita income less than or equal to Brazil's), and the middle-income countries (those with per capita income between Brazil's and Italy's). They find little overlap between such groups - very few people in developing countries have incomes in the range of those in the rich countries.

‣ Can We Discern the Effect of Globalization on Income Distribution? Evidence from Household Budget Surveys

Milanovic, Branko
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
Português
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The effects of globalization on income distribution in rich and poor countries are a matter of controversy. While international trade theory in its most abstract formulation implies that increased trade and foreign investment should make income distribution more equal in poor countries and less equal in rich countries, finding these effects has proved elusive. The author presents another attempt to discern the effects of globalization by using data from household budget surveys and looking at the impact of openness and foreign direct investment on relative income shares of low and high deciles. The author finds some evidence that at very low average income levels, it is the rich who benefit from openness. As income levels rise to those of countries such as Chile, Colombia, or Czech Republic, for example, the situation changes, and it is the relative income of the poor and the middle class that rises compared with the rich. It seems that openness makes income distribution worse before making it better--or differently in that the effect of openness on a country's income distribution depends on the country's initial income level.

‣ Addenbrooke\'s Cognitive Examination - Revised (ACE-R): adaptação transcultural, dados normativos de idosos cognitivamente saudáveis e de aplicabilidade como instrumento de avaliação cognitiva breve para pacientes com doença de Al; Addenbrookes Cognitive ExaminationRevised (ACE-R): cross-cultural adaptation, normative data for cognitively preserved elderly and its applicability as a brief cognitive evaluation tool for mild probable Alzheimers disease patients

Carvalho, Viviane Amaral
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 17/09/2009 Português
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INTRODUÇÃO: A Addenbrookes Cognitive Examination Revised (ACE-R) avalia cinco domínios cognitivos em conjunto e também oferece notas parciais para cada um deles, a saber: Atenção e Orientação, Memória, Fluência, Linguagem e Habilidades VisuaisEspaciais. Essa bateria tem se mostrado útil na diferenciação entre a doença de Alzheimer (DA) e a demência frontotemporal (DFT) em outros países. O instrumento foi submetido à adaptação para o português e sua versão brasileira foi previamente publicada pelos autores. OBJETIVO: Investigar o desempenho de indivíduos idosos cognitivamente saudáveis e de outros com DA provável leve na versão brasileira da ACE-R. MÉTODOS: O teste foi administrado a um grupo de 31 pacientes com DA provável leve e a 114 idosos cognitivamente saudáveis. Destes, 62 foram equiparados aos pacientes por idade e escolaridade. Todos os participantes incluídos tinham idade 60 anos e 4 anos de escolaridade. Não apresentavam sintomatologia depressiva associada, definida como pontuação > 7 na Escala Cornell para Depressão em Demência. O comprometimento cognitivo dos pacientes foi evidenciado por pontuação < 123 na Escala Mattis de Avaliação de Demência (DRS). Os controles apresentaram escore total na DRS 123. Dados normativos foram extraídos da amostra total de indivíduos sadios. Foi analisada a correlação entre a ACE-R e o Teste de Memória de Figuras (BCB-Edu)...

‣ Modeling Spacing Distribution of Queuing Vehicles in Front of a Signalized Junction Using Random-Matrix Theory

Jin, Xuexiang; Su, Yuelong; Zhang, Yi; Li, Li
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/03/2008 Português
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Modeling of headway/spacing between two consecutive vehicles has many applications in traffic flow theory and transport practice. Most known approaches only study the vehicles running on freeways. In this paper, we propose a model to explain the spacing distribution of queuing vehicles in front of a signalized junction based on random-matrix theory. We show that the recently measured spacing distribution data well fit the spacing distribution of a Gaussian symplectic ensemble (GSE). These results are also compared with the spacing distribution observed for car parking problem. Why vehicle-stationary-queuing and vehicle-parking have different spacing distributions (GSE vs GUE) seems to lie in the difference of driving patterns.

‣ Fitting Parton Distribution Data with Multiplicative Normalization Uncertainties

The NNPDF Collaboration; Ball, Richard D.; Del Debbio, Luigi; Forte, Stefano; Guffanti, Alberto; Latorre, Jose I.; Rojo, Juan; Ubiali, Maria
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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We consider the generic problem of performing a global fit to many independent data sets each with a different overall multiplicative normalization uncertainty. We show that the methods in common use to treat multiplicative uncertainties lead to systematic biases. We develop a method which is unbiased, based on a self--consistent iterative procedure. We demonstrate the use of this method by applying it to the determination of parton distribution functions with the NNPDF methodology, which uses a Monte Carlo method for uncertainty estimation.; Comment: 33 pages, 5 figures: published version

‣ Network reconstruction by stationary distribution data of Markov chains based on correlation analysis

He, Zhe; Xu, Rui-Jie; Wang, Bing-Hong
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/10/2014 Português
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We propose a new method for network reconstruction by the stationary distribution data of Markov chains on this network. Our method has the merits that: the data we need are much few than most method and need not defer to the time order, and we do not need the input data. We define some criterions to measure the efficacy and the simulation results on several networks, including computer-generated networks and real networks, indicate our method works well. The method consist of two procedures, fist, reconstruct degree sequence, second, reconstruct the network(or edges). And we test the efficacy of each procedure.; Comment: 4 pages, 3 figures

‣ The Nyquist-Shannon sampling theorem and the atomic pair distribution function

Farrow, Christopher L.; Shaw, Margaret; Kim, Hyunjeong; Juhas, Pavol; Billinge, Simon J. L.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/04/2011 Português
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We have systematically studied the optimal real-space sampling of atomic pair distribution data by comparing refinement results from oversampled and resampled data. Based on nickel and a complex perovskite system, we demonstrate that the optimal sampling is bounded by the Nyquist interval described by the Nyquist-Shannon sampling theorem. Near this sampling interval, the data points in the PDF are minimally correlated, which results in more reliable uncertainty prediction. Furthermore, refinements using sparsely sampled data may run many times faster than using oversampled data. This investigation establishes a theoretically sound limit on the amount of information contained in the PDF, which has ramifications towards how PDF data are modeled.; Comment: 10 pages, 4 figures

‣ Root distribution in apricot orchard (Prunus armeniaca L. ‘Búlida’) under trickle irrigation

Ruiz, A.; Franco, J. A.; Plana, V.; Abrisqueta García, José María
Fonte: International Society for Horticultural Science Publicador: International Society for Horticultural Science
Tipo: Artículo Formato: 579917 bytes; image/jpeg
Português
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En: XIII International Symposium on Apricot Breeding and Culture (Murcia, Spain); Efficient irrigation and fertiliser application requires an understanding of the distribution of roots, water and soil nutrients in the soil profile. Root distribution in a cultivar is important for trickle irrigation design parameters and management. This information is not very contrasted in most situations. The objective of this study was to determine the root distribution in apricot (Prunus armeniaca L. ‘Búlida’), for a plot of 10-year-old trees under trickle irrigation with two irrigation strategies. The experiment was developed in a loam-soil plot in Murcia (Spain). Root distribution was measured in a square grid of 15 points, 3 m long and 100 cm deep. Samples were collected at 10-cm increments. The majority of roots (95%) were located 50 cm deeper under emitters. Apricot root length (RLD) and weight densities increased for low quantities of irrigation water and decreased for high quantities. RLD decreased with depth for the two irrigation strategies. RLD differed 2.5-fold between irrigation strategies, from soil level to 25 cm depth. RLD was similar for the two strategies below 25 cm. Root distribution was fitted to the Greenwood root density distribution model. Root distribution data were used in a water balance experiment.; Peer reviewed

‣ Comparação da distribuição de pressão plantar em sujeitos com pés normais e com pés planos durante a marcha DOI: 10.5007/1980-0037.2010v12n4p290; Comparison of plantar pressure distribution in subjects with normal and flat feet during gait DOI: 10.5007/1980-0037.2010v12n4p290

Nazario, Patrik Felipe; Universidade do Estado de Santa Catarina. Florianópolis, SC. Brasil.; Libardoni dos Santos, João Otacilio; Universidade do Estado de Santa Catarina. Florianópolis, SC. Brasil.; Vargas Avila, Aluisio Otavio; Universidade do Estad
Fonte: Universidade Federal de Santa Catarina. Florianópolis, SC. Brasil Publicador: Universidade Federal de Santa Catarina. Florianópolis, SC. Brasil
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; "Avaliado por Pares",; ; Avaliado por Pares; Pesquisa Descritiva Formato: application/pdf; application/pdf
Publicado em 24/05/2010 Português
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O objetivo do estudo/pesquisa foi verificar possíveis relações entre a queda do arco longitudinal medial, mensurada em situação estática pela altura do osso navicular e um conjunto de variáveis relacionadas à distribuição de pressão plantar, mensuradas em situação dinâmica. Participaram do estudo 11 (onze) sujeitos do gênero masculino, com idade média de 21 anos ± 3 anos, massa corporal 74 kg ± 10 kg e estatura 175 cm ± 4 cm. Para aquisição dos dados de Distribuição de Pressão Plantar (Pico de Pressão, Pressão Média, Área de Contato e Carga Relativa), foi utilizado o Novel Emed-AT System com uma taxa de amostragem de 50 Hz e para análise da Altura do Navicular para classificação dos sujeitos em grupos, foi utilizado o protocolo Navicular Drop Test proposto por Brody (1982). Os dados foram comparados a partir dos resultados da aplicação da estatística não paramétrica através do teste U de Mann-Whitney com p ≤ 0,05. Os resultados demonstraram que os grupos foram significativamente diferentes entre si, na região do mediopé, em todas as variáveis analisadas, sendo que foram encontrados os maiores valores médios no grupo dos indivíduos com os Pés Planos. Também apresentaram diferenças significativas na variável Área de Contato...

‣ The genus Ixodes (Acari: Ixodidae) in Mexico: adult identification keys, diagnoses, hosts, and distribution

Guzmán-Cornejo,Carmen; Robbins,Richard G.
Fonte: Instituto de Biología Publicador: Instituto de Biología
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2010 Português
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Identification keys, diagnoses, hosts, and distribution data are provided for adults of the 26 species of Ixodes known from Mexico. Data are from specimens deposited in the Colección Nacional de Ácaros (CNAC), Instituto de Biología, Universidad Nacional Autónoma de México, and from the literature.

‣ Historical mammal distribution data: how reliable are written records?

Boshoff,Andre F; Kerley,Graham I.H
Fonte: South African Journal of Science Publicador: South African Journal of Science
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2010 Português
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Written historical records are widely used to estimate the previous distributions of the larger mammals in southern Africa. However, such records have some limitations and the use of those older than 100 years has been questioned. Written historical records, from the broader Eastern Cape, South Africa, were investigated to examine this contention critically. They were classified according to record quality (acceptability of identification and precision of locality) and analysed according to two levels: 'all' species and 'noticeable' versus 'non-noticeable' species. Records that comprise acceptable identification and precise locality information are the most suitable for mapping historical distributions; they form 33% of the records for the 27 mammal species analysed. A further 49% of the records have acceptable identification but imprecise locality information; they can fulfil a useful function when supported by records where both parameters are of good quality. Thus, the majority (82%) of written historical records from the study area are useful for compiling historical distribution maps and the quality of these records is consistent back to 1750 for this data set. The number and quality of written historical records varies between species. Historical distribution data should be evaluated for reliability (quality) and degree of usefulness...