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Zhang Zhiwei Z Division of Biostatistics, Office of Surveillance and Biometrics, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MA, - - 2014
We consider the problem of estimating the prevalence of a disease under a group testing framework. Because assays are usually imperfect, misclassification of disease status is a major challenge in prevalence estimation. To account for possible misclassification, it is usually assumed that the sensitivity and specificity of the assay are ...
Saraph V V Computer Science and Engineering, University of Notre Dame, IN 46556, USAComputer Science, Brown University, RI 02912, - - 2014
Biological network alignment aims to identify similar regions between networks of different species. Existing methods compute node similarities to rapidly identify from possible alignments the high-scoring alignments with respect to the overall node similarity. But, the accuracy of the alignments is then evaluated with some other measure that is different ...
Wan Jun - - 2014
In this paper, we propose a novel approach called class-specific maximization of mutual information (CSMMI) using a submodular method, which aims at learning a compact and discriminative dictionary for each class. Unlike traditional dictionary-based algorithms, which typically learn a shared dictionary for all of the classes, we unify the intraclass ...
Park Byung-Jung BJ Department of Transportation Engineering, Myongji University, South Korea. Electronic address: - - 2014
The application of finite mixture regression models has recently gained an interest from highway safety researchers because of its considerable potential for addressing unobserved heterogeneity. Finite mixture models assume that the observations of a sample arise from two or more unobserved components with unknown proportions. Both fixed and varying weight ...
Bamdadian Atieh A Institute for Infocomm Research (I(2)R), Agency for Science, Technology and Research (A*STAR), 1 Fusionopolis Way, #21-01 Connexis, Singapore 138632, Singapore; Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore. Electronic address: - - 2014
One of the main issues in motor imagery-based (MI-based) brain-computer interface (BCI) systems is a large variation in the classification performance of BCI users. However, the exact reason of low performance of some users is still under investigation. Having some prior knowledge about the performance of users may be helpful ...
Reyes Alberto V AV 1] Department of Geoscience, University of Wisconsin-Madison, 1215 West Dayton Street, Madison, Wisconsin 53706, USA [2] School of Geography, Archaeology and Palaeoecology, Queen's University Belfast, Elmwood Avenue, Belfast BT7 1NN, UK [3] Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada (A.V.R); Department of Geosciences, University of Arizona, 1040 East 4th Street, Tucson, Arizona 85721, USA - - 2014
Varying levels of boreal summer insolation and associated Earth system feedbacks led to differing climate and ice-sheet states during late-Quaternary interglaciations. In particular, Marine Isotope Stage (MIS) 11 was an exceptionally long interglaciation and potentially had a global mean sea level 6 to 13 metres above the present level around 410,000 to ...
Tay Darwin - - 2014
Myocardial infarction (MI) is one of the leading causes of death in many developed countries. Hence, early detection of MI events is critical for effective preventative therapies, potentially reducing avoidable mortality. One approach for early disease prediction is the use of risk prediction models developed using machine learning techniques. One ...
Donneau A F AF a Medical Informatics and Biostatistics, Department of Public Health , University of Liège , Liège , - - 2014
Abstract The application of multiple imputation (MI) techniques as a preliminary step to handle missing values in data analysis is well established. The MI method can be classified into two broad classes, the joint modeling and the fully conditional specification approaches. Their relative performance for the longitudinal ordinal data setting ...
Nassar Antonio Paulo AP - - 2014
Simplified Acute Physiology Score 3 (SAPS 3) was the first critical care prognostic model developed from worldwide data. We aimed to systematically review studies that assessed the prognostic performance of SAPS 3 general and customized models for predicting hospital mortality in adult patients admitted to the ICU. Medline, Lilacs, Scielo ...
Bartlett Jonathan W JW Centre for Statistical Methodology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK - - 2014
Missing values in covariates of regression models are a pervasive problem in empirical research. Popular approaches for analyzing partially observed datasets include complete case analysis (CCA), multiple imputation (MI), and inverse probability weighting (IPW). In the case of missing covariate values, these methods (as typically implemented) are valid under different ...
Morris Tim P - - 2014
Multiple imputation is a commonly used method for handling incomplete covariates as it can providevalid inference when data are missing at random. This depends on being able to correctly specify theparametric model used to impute missing values, which may be difficult in many realistic settings.Imputation by predictive mean matching (PMM) ...
Dreassi Emanuela E Dipartimento di Statistica, Informatica, Applicazioni, Università di Firenze, Firenze, Italy - - 2014
Lung cancer incidence over 2005-2010 for 326 Local Authority Districts in England is investigated by ecological regression. Motivated from mis-specification of a Negative Binomial additive model, a semiparametric Negative Binomial M-quantile regression model is introduced. The additive part relates to those univariate or bivariate smoothing components, which are included in ...
Lorenz Romy R Machine Learning Laboratory, Berlin Institute of Technology, Berlin, - - 2014
Objective. In recent years, brain-computer interfaces (BCIs) have become mature enough to immensely benefit from the expertise and tools established in the field of human-computer interaction (HCI). One of the core objectives in HCI research is the design of systems that provide a pleasurable user experience (UX). While the majority ...
Yang Huijuan H Institute for Infocomm Research, Agency for Science, Technology and Research (A*STAR), - - 2014
Objective. Detection of motor imagery of hand/arm has been extensively studied for stroke rehabilitation. This paper firstly investigates the detection of motor imagery of swallow (MI-SW) and motor imagery of tongue protrusion (MI-Ton) in an attempt to find a novel solution for post-stroke dysphagia rehabilitation. Detection of MI-SW from a ...
Magill Molly - - 2014
Objective: The technical hypothesis of motivational interviewing (MI) posits that therapist-implemented MI skills are related to client speech regarding behavior change and that client speech predicts client outcome. The current meta-analysis is the first aggregate test of this proposed causal model. Method: A systematic literature review, using stringent inclusion criteria, ...
Welch Catherine A CA Department of Primary Care and Population Health, University College London (UCL), London, - - 2014
Most implementations of multiple imputation (MI) of missing data are designed for simple rectangular data structures ignoring temporal ordering of data. Therefore, when applying MI to longitudinal data with intermittent patterns of missing data, some alternative strategies must be considered. One approach is to divide data into time blocks and ...
Brennan Victoria K VK RTI Health Solutions, Health Economics, 2nd Floor, The Pavilion, Towers Business Park, Wilmslow Road, Manchester, M20 2LS United - - 2014
Abstract Objective: To identify cost estimates related to myocardial infarction (MI) or stroke in patients with type 2 diabetes mellitus (T2DM) for use in economic models. Methods: A systematic literature review was conducted. Electronic databases and conference abstracts were screened against inclusion criteria, which included studies performed in patients who ...
Rodwell Laura - - 2014
Multiple imputation (MI) was developed as a method to enable valid inferences to be obtained in the presence of missing data rather than to re-create the missing values. Within the applied setting, it remains unclear how important it is that imputed values should be plausible for individual observations. One variable ...
Atkins David C - - 2014
Behavioral interventions such as psychotherapy are leading, evidence-based practices for a variety of problems (e.g., substance abuse), but the evaluation of provider fidelity to behavioral interventions is limited by the need for human judgment. The current study evaluated the accuracy of statistical text classification in replicating human-based judgments of provider ...
Perdikis S S Chair in Non-Invasive Brain-Machine Interface, Center for Neuroprosthetics, School of Engineering, École Polytechnique Fédérale de Lausanne, Station 11, 1015 Lausanne, - - 2014
Objective. While brain-computer interfaces (BCIs) for communication have reached considerable technical maturity, there is still a great need for state-of-the-art evaluation by the end-users outside laboratory environments. To achieve this primary objective, it is necessary to augment a BCI with a series of components that allow end-users to type text ...
Shin Hyeong-Moo - - 2014
Estimated historical exposures and serum concentrations of perfluorooctanoic acid (PFOA) have been extensively used in epidemiologic studies that examined associations between PFOA exposures and adverse health outcomes among residents in highly exposed areas in the Mid-Ohio Valley. Using measured serum PFOA levels in 2005-2006, we applied two calibration methods to ...
Zhan Yu Y Department of Land, Air, and Water Resources, University of California, Davis, CA, 95616, - - 2014
Published studies relating pyrethroid use and subsequent mite outbreaks were largely based on laboratory and field experiments, with some inferring a result of increased miticide use. This study derived a mathematical model proposed to quantify the effect of pyrethroid use intensity on mite population density. The model was validated against ...
Nieh Chiping C Division of Environmental and Occupational Health Sciences, School of Public Health, University of Illinois at Chicago, 2121 W. Taylor Street, Chicago, IL 60612-7260, USA. - - 2014
Longitudinal studies of microbial water quality are subject to missing observations. This study evaluates multiple imputation (MI) against data deletion, mean or median imputation for replacing missing microbial water quality data. The specific context is data collected in Chicago Area Waterway System (2007-2009), where 45% of Escherichia coli and 53% ...
Chou Chun-An - - 2014
Multi-voxel pattern analysis (MVPA) of functional magnetic resonance imaging (fMRI) data is an emerging approach for probing the neural correlates of cognition. MVPA allows cognitive states to be modeled as distributed patterns of neural activity and classified according to stimulus conditions. In practice, building a robust, generalizable classification model can ...
Su Li M LM Key Laboratory for Wetland Ecology and Vegetation Restoration of National Environmental Protection, School of Environment, Northeast Normal University, Changchun, Jilin 130117, PR - - 2014
Toxic ratio TR is a valuable tool in the discrimination of excess toxicity from baseline effect. Although some authors realized that internal effect concentration or critical body residual (CBR) calculated from bioconcentration factor (BCF) should be used in the TR, the effect of BCF on the discrimination of excess toxicity ...
Dayan Peter P Gatsby Computational Neuroscience Unit, University College - - 2014
Although seemingly irrational choice abounds, the rules governing these mis-steps that might provide hints about the factors limiting normative behavior are unclear. We consider three experimental tasks, which probe different aspects of non-normative choice under uncertainty. We argue for systematic statistical, algorithmic, and implementational sources of irrationality, including incomplete evaluation ...
Ledermann Thomas - - 2014
For the study of growth in dyads, methods have been developed to analyze growth at the level of the dyad members. In this article, we present a novel approach that we call the Common Fate Growth Model (CFGM). This model permits an analysis of growth at the level of the ...
Hsu Wei-Yen WY Department of Information Management, National Chung Cheng - - 2014
A novel method for motor imagery (MI) electroencephalogram (EEG) data classification is proposed in this study. Time-frequency representation is constructed by means of continuous wavelet transform from EEG signals and then weighted with 2-sample t-statistics, which are also used to automatically select the area of interest in advance. Finally, normalized ...
Hall Brittany C - - 2014
The purpose of this study was to determine how three different measures of motivation (cognitive motivation, taking steps, and self-efficacy for change and maintenance) predict substance use outcomes after engaging in a Motivational Interviewing intervention. Participants were 225 high school students enrolled in Project Reducing the Effects of Alcohol and ...
Martínez-López B B Center for Animal Disease Modeling and Surveillance, VM: Medicine and Epidemiology, UC Davis, CA, USA; VISAVET, Veterinary School, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040, Spain; IREC (CSIC-UCLM-JCCM), Ronda de Toledo s/n, 13005 Ciudad Real, Spain. Electronic address: - - 2014
This study presents a multi-disciplinary decision-support tool, which integrates geo-statistics, social network analysis (SNA), spatial-stochastic spread model, economic analysis and mapping/visualization capabilities for the evaluation of the sanitary and socio-economic impact of livestock diseases under diverse epidemiologic scenarios. We illustrate the applicability of this tool using foot-and-mouth disease (FMD) in ...
Rumsey Ian Cooper - - 2014
Hydrogen sulfide (H2S) emissions were determined from an anaerobic lagoon at a swine concentrated animal feeding operation (CAFO) in North Carolina. Measurements of H2S were made continuously from an anaerobic lagoon using a dynamic flow-through chamber for ≈1 week during each of the four seasonal periods from June 2007 through ...
Lau Max S Y MS Maxwell Institute for Mathematical Sciences, Heriot-Watt University, , Edinburgh EH14 4AS, - - 2014
A cardinal challenge in epidemiological and ecological modelling is to develop effective and easily deployed tools for model assessment. The availability of such methods would greatly improve understanding, prediction and management of disease and ecosystems. Conventional Bayesian model assessment tools such as Bayes factors and the deviance information criterion (DIC) ...
Guo Xiaobo X Department of Statistical Science, School of Mathematics & Computational Science, Sun Yat-Sen University, Guangzhou, China ; Southern China Research Center of Statistical Science, Sun Yat-Sen University, Guangzhou, China ; State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, - - 2014
Nonlinear dependence is general in regulation mechanism of gene regulatory networks (GRNs). It is vital to properly measure or test nonlinear dependence from real data for reconstructing GRNs and understanding the complex regulatory mechanisms within the cellular system. A recently developed measurement called the distance correlation (DC) has been shown ...
Ross Brian C BC Department of Physics, University of Washington, Seattle, Washington, United States of - - 2014
Mutual information (MI) is a powerful method for detecting relationships between data sets. There are accurate methods for estimating MI that avoid problems with "binning" when both data sets are discrete or when both data sets are continuous. We present an accurate, non-binning MI estimator for the case of one ...
Billinger Martin M Institute for Knowledge Discovery, Graz University of Technology Graz, - - 2014
Analysis of brain connectivity has become an important research tool in neuroscience. Connectivity can be estimated between cortical sources reconstructed from the electroencephalogram (EEG). Such analysis often relies on trial averaging to obtain reliable results. However, some applications such as brain-computer interfaces (BCIs) require single-trial estimation methods. In this paper, ...
McCormick Natalie N Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada; Arthritis Research Centre of Canada, Richmond, British Columbia, - - 2014
Though administrative databases are increasingly being used for research related to myocardial infarction (MI), the validity of MI diagnoses in these databases has never been synthesized on a large scale. To conduct the first systematic review of studies reporting on the validity of diagnostic codes for identifying MI in administrative ...
Ghasemi Omid - - 2014
Inflammation and extracellular matrix (ECM) remodeling are important components regulating the response of the left ventricle to myocardial infarction (MI). Significant cellular- and molecular-level contributors can be identified by analyzing data acquired through high-throughput genomic and proteomic technologies that provide expression levels for thousands of genes and proteins. Large-scale data ...
Fisher Charles K CK Department of Physics, Boston University, Boston, Massachusetts, United States of - - 2014
Human associated microbial communities exert tremendous influence over human health and disease. With modern metagenomic sequencing methods it is now possible to follow the relative abundance of microbes in a community over time. These microbial communities exhibit rich ecological dynamics and an important goal of microbial ecology is to infer ...
Drake Tom T London School of Hygiene and Tropical Medicine, Kepple Street, London, WC1E 7HT, UK, Nuffield Department of Clinical Medicine, University of Oxford, Old Road Campus, Oxford, OX3 7BN, UK, Mahidol University Rajvithi Road, Bangkok 10400, Thailand and National University of Singapore, Lower Kent Ridge Road, Singapore - - 2013
Investment in pandemic preparedness is a long-term gamble, with the return on investment coming at an unknown point in the future. Many countries have chosen to stockpile key resources, and the number of pandemic economic evaluations has risen sharply since 2009. We assess the importance of uncertainty in time-to-pandemic (and ...
Lee Katherine J KJ Clinical Epidemiology and Biostatistics Unit, Murdoch Childrens Research Institute, Melbourne, Victoria, Australia; Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, - - 2013
Missing data are common in both observational and experimental studies. Multiple imputation (MI) is a two-stage approach where missing values are imputed a number of times using a statistical model based on the available data and then inference is combined across the completed datasets. This approach is becoming increasingly popular ...
Yoon Myeongsun M Department of Educational Psychology, Texas A&M University, College Station, TX, 77843-4225, USA, - - 2013
The purpose of this study was to examine the performance of modification indices (MIs) in finding correct partial invariance models when testing factorial invariance across groups of interest. In the present study, we examined the two commonly used approaches in this area-namely, nonsequential search and sequential search. Using the nonsequential ...
Douka Katerina K Research Laboratory for Archaeology and the History of Art, University of Oxford, Dyson Perrins Building, South Parks Road, Oxford OX1 3QY, UK. Electronic address: - - 2013
The 1950s excavations by Charles McBurney in the Haua Fteah, a large karstic cave on the coast of northeast Libya, revealed a deep sequence of human occupation. Most subsequent research on North African prehistory refers to his discoveries and interpretations, but the chronology of its archaeological and geological sequences has ...
Clavel Julien J Laboratoire de Géologie de Lyon, UMR 5276, CNRS, UCB Lyon 1, ENS Lyon, Campus de la Doua, 2 rue Raphaël Dubois, 69622 Villeurbanne Cedex, France. julien.clavel@univ-lyon1.fr, - - 2013
Fossil-based estimates of diversity and evolutionary dynamics mainly rely on the study of morphological variation. Unfortunately, organism remains are often altered by post-mortem taphonomic processes such as weathering or distortion. Such a loss of information often prevents quantitative multivariate description and statistically controlled comparisons of extinct species based on morphometric ...
Isma'eel Hussain A - - 2013
The unpredictability of acenocoumarol dose needed to achieve target blood thinning level remains a challenge. We aimed to apply and compare a pharmacogenetic least-squares model (LSM) and artificial neural network (ANN) models for predictions of acenocoumarol dosing. LSM and ANN models were used to analyze previously collected data on 174 ...
Harris Alex H S - - 2013
This commentary discusses the paper by Hallgren and Witkiewitz (2013) which evaluated 5 methods for addressing missing data in clinical trials of interventions for alcohol use disorders. The authors conclude that commonly used methods (e.g., complete case analysis, single imputation methods) can produce misleading results and that better alternatives exist ...
Eekhout Iris - - 2013
Regardless of the proportion of missing values, complete-case analysis is most frequently applied, although advanced techniques such as multiple imputation (MI) are available. The objective of this study was to explore the performance of simple and more advanced methods for handling missing data in cases when some, many, or all ...
Imel Zac E - - 2013
Empathy is a critical ingredient in motivational interviewing (MI) and in psychotherapy generally. It is typically defined as the ability to experience and understand the feelings of another. Basic science indicates that empathy is related to the development of synchrony in dyads. However, in clinical research, empathy has proved difficult ...
Sun Wanjie - - 2013
In longitudinal studies, a quantitative outcome (such as blood pressure) may be altered during follow-up by the administration of a non-randomized, non-trial intervention (such as anti-hypertensive medication) that may seriously bias the study results. Current methods mainly address this issue for cross-sectional studies. For longitudinal data, the current methods are ...
Rendall Michael S - - 2013
Within-survey multiple imputation (MI) methods are adapted to pooled-survey regression estimation where one survey has more regressors, but typically fewer observations, than the other. This adaptation is achieved through: (1) larger numbers of imputations to compensate for the higher fraction of missing values; (2) model-fit statistics to check the assumption ...
Li Qizhai - - 2013
A classical approach to combine independent test statistics is Fisher's combination of $p$-values, which follows the $\chi ^2$ distribution. When the test statistics are dependent, the gamma distribution (GD) is commonly used for the Fisher's combination test (FCT). We propose to use two generalizations of the GD: the generalized and ...
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