998 resultados para 230204 Applied Statistics
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The IDPH Public Health Tracking Program is an excellent way to collect data related to various indicators for Iowans, but those looking for national statistics or data from other states may want to check out the Health Indicators Warehouse (healthindicators.gov). Run and maintained by the CDC’s National Center for Health Statistics, this site is a centralized source for national, state, and county data for a wide variety of indicators. The data is available to the public, and can be accessed either through the tables and charts directly on the website, or indicators can be downloaded to use in a spreadsheet. Once on the site, users are able to search for their desired data either by topic or geographic region. Filters can then be applied to the chosen field to narrow down the user’s search and obtain the preferred statistics. In addition, users are also able to search for indicators derived from state and federal health indicator initiatives: County Health Rankings, Community Health Status Indicators, Healthy People 2020, and CMS Community Indicators. The warehouse provides an overview of each indicator after the user has made their selection. This overview includes information on how the data was calculated and what characteristics are being represented. For example, percent of binge drinking adults is prefaced in the overview that data was based on the question: “Considering all types of alcoholic beverages, how many times during the past 30 days did you have [5 for men, 4 for women] or more drinks on an occasion?" Data is viewable either in the basic table format, chart format, or for some indicators it is possible to view it in terms of a national map. The Health Indicators Warehouse updates indicators as data becomes available, but the collection of years varies amongst the indicators. Nonetheless, this site is a useful resource to anyone looking for comparative indicators throughout the nation or is interested in one of the hundreds of indicators housed by the site. For more information or to check out what the warehouse has to offer visit: http://healthindicators.gov/
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Background Obesity may have an impact on key aspects of health-related quality of life (HRQOL). In this context, the Impact of Weight Quality of Life (IWQOL) questionnaire was the first scale designed to assess HRQOL. The aim of the present study was twofold: to assess HRQOL in a sample of Spanish patients awaiting bariatric surgery and to determine the psychometric properties of the IWQOL-Lite and its sensitivity to detect differences in HRQOL across groups. Methods Participants were 109 obese adult patients (BMI¿ 35 kg/m2) from Barcelona, to whom the following measurement instruments were applied: IWQOL-Lite, Depression Anxiety Stress Scales, Brief Symptom Inventory, and self-perception items. Results Descriptive data regarding the IWQOL-Lite scores obtained by these patients are reported. Principal components analysis revealed a five-factor model accounting for 72.05% of the total variance, with factor loadings being adequate for all items. Corrected itemtotal correlations were acceptable for all items. Cronbach"s alpha coefficients were excellent both for the subscales (0.880.93) and the total scale (0.95). The relationship between the IWQOLLite and other variables supports the construct validity of the scale. Finally, sensitivity analysis revealed large effect sizes when comparing scores obtained by extreme BMI groups. Conclusions This is the first study to report the application of the IWQOL-Lite to a sample of Spanish patients awaiting bariatric surgery and to confirm that the Spanish version of the instrument has adequate psychometric properties.
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The present study discusses retention criteria for principal components analysis (PCA) applied to Likert scale items typical in psychological questionnaires. The main aim is to recommend applied researchers to restrain from relying only on the eigenvalue-than-one criterion; alternative procedures are suggested for adjusting for sampling error. An additional objective is to add evidence on the consequences of applying this rule when PCA is used with discrete variables. The experimental conditions were studied by means of Monte Carlo sampling including several sample sizes, different number of variables and answer alternatives, and four non-normal distributions. The results suggest that even when all the items and thus the underlying dimensions are independent, eigenvalues greater than one are frequent and they can explain up to 80% of the variance in data, meeting the empirical criterion. The consequences of using Kaiser"s rule are illustrated with a clinical psychology example. The size of the eigenvalues resulted to be a function of the sample size and the number of variables, which is also the case for parallel analysis as previous research shows. To enhance the application of alternative criteria, an R package was developed for deciding the number of principal components to retain by means of confidence intervals constructed about the eigenvalues corresponding to lack of relationship between discrete variables.
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Depth-averaged velocities and unit discharges within a 30 km reach of one of the world's largest rivers, the Rio Parana, Argentina, were simulated using three hydrodynamic models with different process representations: a reduced complexity (RC) model that neglects most of the physics governing fluid flow, a two-dimensional model based on the shallow water equations, and a three-dimensional model based on the Reynolds-averaged Navier-Stokes equations. Row characteristics simulated using all three models were compared with data obtained by acoustic Doppler current profiler surveys at four cross sections within the study reach. This analysis demonstrates that, surprisingly, the performance of the RC model is generally equal to, and in some instances better than, that of the physics based models in terms of the statistical agreement between simulated and measured flow properties. In addition, in contrast to previous applications of RC models, the present study demonstrates that the RC model can successfully predict measured flow velocities. The strong performance of the RC model reflects, in part, the simplicity of the depth-averaged mean flow patterns within the study reach and the dominant role of channel-scale topographic features in controlling the flow dynamics. Moreover, the very low water surface slopes that typify large sand-bed rivers enable flow depths to be estimated reliably in the RC model using a simple fixed-lid planar water surface approximation. This approach overcomes a major problem encountered in the application of RC models in environments characterised by shallow flows and steep bed gradients. The RC model is four orders of magnitude faster than the physics based models when performing steady-state hydrodynamic calculations. However, the iterative nature of the RC model calculations implies a reduction in computational efficiency relative to some other RC models. A further implication of this is that, if used to simulate channel morphodynamics, the present RC model may offer only a marginal advantage in terms of computational efficiency over approaches based on the shallow water equations. These observations illustrate the trade off between model realism and efficiency that is a key consideration in RC modelling. Moreover, this outcome highlights a need to rethink the use of RC morphodynamic models in fluvial geomorphology and to move away from existing grid-based approaches, such as the popular cellular automata (CA) models, that remain essentially reductionist in nature. In the case of the world's largest sand-bed rivers, this might be achieved by implementing the RC model outlined here as one element within a hierarchical modelling framework that would enable computationally efficient simulation of the morphodynamics of large rivers over millennial time scales. (C) 2012 Elsevier B.V. All rights reserved.
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Selostus: Yrttien ja vihannesten infrapunakuivaus rumpukuivurissa
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Bone metastases are the result of a primary cancer invasion which spreads into the bone marrow through the lymphogenous or hematogenous pathways. Bone metastases are a common complication of cancer.The primary cancers that most frequently metastasize to bone are breast and prostate cancer (65 - 75 %) amongst many others (thyroid 42 %, lung 36 % or kidney 35 %) (Suva et al., 2011). Although the exact incidence of bone metastases is unknown given its dependence on the type of primary cancer, it is estimated that 350,000 people die of bone metastases annually in the United States.
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The IDPH Public Health Tracking Program is an excellent way to collect data related to various indicators for Iowans, but those looking for national statistics or data from other states may want to check out the Health Indicators Warehouse (healthindicators.gov). Run and maintained by the CDC’s National Center for Health Statistics, this site is a centralized source for national, state, and county data for a wide variety of indicators. The data is available to the public, and can be accessed either through the tables and charts directly on the website, or indicators can be downloaded to use in a spreadsheet. Once on the site, users are able to search for their desired data either by topic or geographic region. Filters can then be applied to the chosen field to narrow down the user’s search and obtain the preferred statistics. In addition, users are also able to search for indicators derived from state and federal health indicator initiatives: County Health Rankings, Community Health Status Indicators, Healthy People 2020, and CMS Community Indicators. The warehouse provides an overview of each indicator after the user has made their selection. This overview includes information on how the data was calculated and what characteristics are being represented. For example, percent of binge drinking adults is prefaced in the overview that data was based on the question: “Considering all types of alcoholic beverages, how many times during the past 30 days did you have [5 for men, 4 for women] or more drinks on an occasion?" Data is viewable either in the basic table format, chart format, or for some indicators it is possible to view it in terms of a national map. The Health Indicators Warehouse updates indicators as data becomes available, but the collection of years varies amongst the indicators. Nonetheless, this site is a useful resource to anyone looking for comparative indicators throughout the nation or is interested in one of the hundreds of indicators housed by the site. For more information or to check out what the warehouse has to offer visit: http://healthindicators.gov/
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Rhythmic activity plays a central role in neural computations and brain functions ranging from homeostasis to attention, as well as in neurological and neuropsychiatric disorders. Despite this pervasiveness, little is known about the mechanisms whereby the frequency and power of oscillatory activity are modulated, and how they reflect the inputs received by neurons. Numerous studies have reported input-dependent fluctuations in peak frequency and power (as well as couplings across these features). However, it remains unresolved what mediates these spectral shifts among neural populations. Extending previous findings regarding stochastic nonlinear systems and experimental observations, we provide analytical insights regarding oscillatory responses of neural populations to stimulation from either endogenous or exogenous origins. Using a deceptively simple yet sparse and randomly connected network of neurons, we show how spiking inputs can reliably modulate the peak frequency and power expressed by synchronous neural populations without any changes in circuitry. Our results reveal that a generic, non-nonlinear and input-induced mechanism can robustly mediate these spectral fluctuations, and thus provide a framework in which inputs to the neurons bidirectionally regulate both the frequency and power expressed by synchronous populations. Theoretical and computational analysis of the ensuing spectral fluctuations was found to reflect the underlying dynamics of the input stimuli driving the neurons. Our results provide insights regarding a generic mechanism supporting spectral transitions observed across cortical networks and spanning multiple frequency bands.
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Statistics occupies a prominent role in science and citizens' daily life. This article provides a state-of-the-art of the problems associated with statistics in science and in society, structured along the three paradigms defined by Bauer, Allum and Miller (2007). It explores in more detail medicine and public understanding of science on the one hand, and risks and surveys on the other. Statistics has received a good deal of attention; however, very often handled in terms of deficit - either of scientists or of citizens. Many tools have been proposed to improve statistical literacy, the image of and trust in statistics, but with little understanding of their roots, with little coordination among stakeholders and with few assessments of impacts. These deficiencies represent as many new and promising directions in which the PUS research agenda could be expanded.
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This publication is an historical recording of the most requested statistics on vital events and is a source of information that can be used in further analysis.
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This publication is an historical recording of the most requested statistics on vital events and is a source of information that can be used in further analysis.