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1	The plant phenology monitoring design for The National Ecological Observatory Network Elmendorf, Sarah C., Jones, Katherine D., Cook, Benjamin I., Diez, Jeffrey M., Enquist, Carolyn A. F., Hufft, Rebecca A., Jones, Matthew O., Mazer, Susan J., Miller-Rushing, Abraham J., Moore, David J. P., Schwartz, Mark D., Weltzin, Jake F. 04 1900 (has links) Phenology is an integrative science that comprises the study of recurring biological activities or events. In an era of rapidly changing climate, the relationship between the timing of those events and environmental cues such as temperature, snowmelt, water availability, or day length are of particular interest. This article provides an overview of the observer-based plant phenology sampling conducted by the U.S. National Ecological Observatory Network (NEON), the resulting data, and the rationale behind the design. Trained technicians will conduct regular in situ observations of plant phenology at all terrestrial NEON sites for the 30-yr life of the observatory. Standardized and coordinated data across the network of sites can be used to quantify the direction and magnitude of the relationships between phenology and environmental forcings, as well as the degree to which these relationships vary among sites, among species, among phenophases, and through time. Vegetation at NEON sites will also be monitored with tower-based cameras, satellite remote sensing, and annual high-resolution airborne remote sensing. Ground-based measurements can be used to calibrate and improve satellite-derived phenometrics. NEON's phenology monitoring design is complementary to existing phenology research efforts and citizen science initiatives throughout the world and will produce interoperable data. By collocating plant phenology observations with a suite of additional meteorological, biophysical, and ecological measurements (e.g., climate, carbon flux, plant productivity, population dynamics of consumers) at 47 terrestrial sites, the NEON design will enable continental-scale inference about the status, trends, causes, and ecological consequences of phenological change. long-term monitoring NEON open-source data plant phenology sample design Special Feature: NEON Design
2	Interval Estimation for Linear Functions of Medians in Within-Subjects and Mixed Designs Bonett, Douglas G., Price, Robert M. 01 May 2020 (has links) The currently available distribution-free confidence interval for a difference of medians in a within-subjects design requires an unrealistic assumption of identical distribution shapes. A confidence interval for a general linear function of medians is proposed for within-subjects designs that do not assume identical distribution shapes. The proposed method can be combined with a method for linear functions of independent medians to provide a confidence interval for a linear function of medians in mixed designs. Simulation results show that the proposed methods have good small-sample properties under a wide range of conditions. The proposed methods are illustrated with examples, and R functions that implement the new methods are provided. confidence intervals distribution-free longitudinal design paired-sample design pretest–posttest design robust Mathematics and Statistics
3	Importância do mapeamento de habitats e do planejamento amostral no processo de avaliação de impactos ambientais sobre comunidades bentônicas de fundos não consolidados / Importance of habitat mapping and sample design in the environmental impacts assessment on benthic communities of unconsolidated bottoms Zanin, Gimel Roberto 11 November 2013 (has links) O presente estudo realizou uma análise crítica do planejamento amostral de comunidades bentônicas de substratos inconsolidados. Para tal, foram realizadas análises de custo-benefício dos desenhos amostrais estratificados e não estratificados em ambiente computacional, através das estimativas de exatidão e precisão da amostragem. Os desenhos estratificados apresentaram melhor custo-benefício (mais exatos) do que os não estratificados, sendo que o desenho estratificado-hierarquizado foi considerado o mais custo-eficiente, com melhor precisão em comparação ao estratificado-aleatorizado. Além disso, desenho e esforço amostrais, descritor de comunidade, poder estatístico e complexidade da comunidade bentônica influenciaram a precisão da amostragem. Os conceitos obtidos foram testados em conjunto de dados reais, coletados na Enseada de Caraguatatuba (SP), com vistas à sua aplicação no âmbito do licenciamento ambiental. As tendências observadas para dados reais convergiram com as obtidas nos cenários computacionais. Quanto à aplicação no licenciamento ambiental, constatou-se que diferentes setores da sociedade divergem quanto ao número mínimo de amostras necessário para alcançar níveis adequados de precisão na avaliação de impactos ambientais. Os ambientalistas foram os mais conservadores e a comunidade científica os menos conservadores. Ainda, tanto no cenário virtual quanto no real, uma precisão de 10% resultou em esforços amostrais viáveis financeira e logisticamente, assegurando poder estatístico de 90% no teste de hipóteses / This study performed a critical analysis of the sampling planning of benthic communities in unconsolidated substrates. Cost-benefit analysis of the stratified and non-stratified sample designs were conducted in computational environment, through estimates of sampling accuracy and precision. Thestratified designs presented better cost-benefit results than the non-stratified ones, and the stratified-hierarchical design was considered the most costefficient, with better precision compared to the stratified-randomized. In addition, sampling design and effort, community descriptor, statistical power and complexity of the benthic community influenced sampling precision. These concepts were applied to real data sets collected in Caraguatatuba Bay (SP), with perspectives to its application in environmental licensing. The observed trends for real data converged with the computational scenarios. Regarding its applications for environmental licensing, it was observed that different groups in the society disagreed about the minimum number of samples necessary to achieve adequate precision in environmental impact assessment. Environmentalists were the most conservative group, while members of the scientific community were the least conservative one. Finally, both in real and virtual scenarios, a precision of 10% resulted in sampling efforts which were financially and logistically feasible, assuring a statistical power of 90% in hypothesis testing análise de custo-benefício avaliação de impactos ambientais benthic community comunidade bentônica cost-benefit analysis environmental impact assessment estrutura de habitats habitats structure planejamento amostral sample design
4	Importância do mapeamento de habitats e do planejamento amostral no processo de avaliação de impactos ambientais sobre comunidades bentônicas de fundos não consolidados / Importance of habitat mapping and sample design in the environmental impacts assessment on benthic communities of unconsolidated bottoms Gimel Roberto Zanin 11 November 2013 (has links) O presente estudo realizou uma análise crítica do planejamento amostral de comunidades bentônicas de substratos inconsolidados. Para tal, foram realizadas análises de custo-benefício dos desenhos amostrais estratificados e não estratificados em ambiente computacional, através das estimativas de exatidão e precisão da amostragem. Os desenhos estratificados apresentaram melhor custo-benefício (mais exatos) do que os não estratificados, sendo que o desenho estratificado-hierarquizado foi considerado o mais custo-eficiente, com melhor precisão em comparação ao estratificado-aleatorizado. Além disso, desenho e esforço amostrais, descritor de comunidade, poder estatístico e complexidade da comunidade bentônica influenciaram a precisão da amostragem. Os conceitos obtidos foram testados em conjunto de dados reais, coletados na Enseada de Caraguatatuba (SP), com vistas à sua aplicação no âmbito do licenciamento ambiental. As tendências observadas para dados reais convergiram com as obtidas nos cenários computacionais. Quanto à aplicação no licenciamento ambiental, constatou-se que diferentes setores da sociedade divergem quanto ao número mínimo de amostras necessário para alcançar níveis adequados de precisão na avaliação de impactos ambientais. Os ambientalistas foram os mais conservadores e a comunidade científica os menos conservadores. Ainda, tanto no cenário virtual quanto no real, uma precisão de 10% resultou em esforços amostrais viáveis financeira e logisticamente, assegurando poder estatístico de 90% no teste de hipóteses / This study performed a critical analysis of the sampling planning of benthic communities in unconsolidated substrates. Cost-benefit analysis of the stratified and non-stratified sample designs were conducted in computational environment, through estimates of sampling accuracy and precision. Thestratified designs presented better cost-benefit results than the non-stratified ones, and the stratified-hierarchical design was considered the most costefficient, with better precision compared to the stratified-randomized. In addition, sampling design and effort, community descriptor, statistical power and complexity of the benthic community influenced sampling precision. These concepts were applied to real data sets collected in Caraguatatuba Bay (SP), with perspectives to its application in environmental licensing. The observed trends for real data converged with the computational scenarios. Regarding its applications for environmental licensing, it was observed that different groups in the society disagreed about the minimum number of samples necessary to achieve adequate precision in environmental impact assessment. Environmentalists were the most conservative group, while members of the scientific community were the least conservative one. Finally, both in real and virtual scenarios, a precision of 10% resulted in sampling efforts which were financially and logistically feasible, assuring a statistical power of 90% in hypothesis testing análise de custo-benefício avaliação de impactos ambientais comunidade bentônica estrutura de habitats planejamento amostral benthic community cost-benefit analysis environmental impact assessment habitats structure sample design
5	Estimating Per-pixel Classification Confidence of Remote Sensing Images Jiang, Shiguo 19 December 2012 (has links) No description available. Geographic Information Science Geography Remote Sensing spatial data quality GIS remote sensing image classification classification confidence sample design classification error posterior probability entropy maximum likelihood support vector machine neural network boosted decision tree
6	A Logistic Regression Analysis of Utah Colleges Exit Poll Response Rates Using SAS Software Stevenson, Clint W. 27 October 2006 (has links) (PDF) In this study I examine voter response at an interview level using a dataset of 7562 voter contacts (including responses and nonresponses) in the 2004 Utah Colleges Exit Poll. In 2004, 4908 of the 7562 voters approached responded to the exit poll for an overall response rate of 65 percent. Logistic regression is used to estimate factors that contribute to a success or failure of each interview attempt. This logistic regression model uses interviewer characteristics, voter characteristics (both respondents and nonrespondents), and exogenous factors as independent variables. Voter characteristics such as race, gender, and age are strongly associated with response. An interviewer's prior retail sales experience is associated with whether a voter will decide to respond to a questionnaire or not. The only exogenous factor that is associated with voter response is whether the interview occurred in the morning or afternoon. Exit Poll sampling weighting questionnaires interviewers voters polling places precincts backward selection SAS proc logistic surveylogistic model selection Utah Colleges Exit Poll UCEP SUDAAN SQL data management weight adjustments predicted probabilities logistic regression holdout research validation sample design data architecture adjustment exogenous statistics political science voters nonresponse response rate retail sales age race gender time of day Statistics and Probability

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