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Gianola Daniel   2010
A twostep procedure is presented for analysis of theta (FST) statistics obtained for a battery of loci, which eventually leads to a clustered structure of values. The first step uses a simple Bayesian model for drawing samples from posterior distributions of thetaparameters, but without constructing Markov chains. This step assigns ...


Tiwari Hemant K   2010
Hoffman et al. [1] proposed an elegant resampling method for analyzing clustered binary data. The focus of their paper was to perform association tests on clustered binary data using withinclusterresampling (WCR) method. Follmann et al. [2] extended Hoffman et al.'s procedure more generally with applicability to angular data, combining of ...


Realistic spatial and temporal earthquake distributions in a modified OlamiFederChristensen model.
Jagla E A   2010
The OlamiFederChristensen model describes a limiting case of an elastic surface that slides on top of a substrate and is one of the simplest models that display some features observed in actual seismicity patterns. However, temporal and spatial correlations of real earthquakes are not correctly described by this model in ...


Resendes Ana Paula da Costa   2010
To identify areas at risk of dengue transmission by means of cluster analysis. A cluster analysis in which the primary analysis units were the 48 districts of the municipality of Niterói, Southeastern Brazil, was conducted. The districts were grouped into six strata according to sociodemographic conditions, using the kmeans cluster ...


Franz Thomas   2010
This study was concerned with the cluster analysis of saphenous vein graft data to determine a minimum number of diameters, and their values, for the constrictive smoothing of diameter irregularities of a cohort of veins. Mathematical algorithms were developed for data selection, transformation and clustering. Constrictive diameter values were identified ...


Iwasa Masatomo   2010
Swarm oscillator model derived by one of the authors (Tanaka), where interacting motile elements form various kinds of patterns, is investigated. We particularly focus on the cluster patterns in onedimensional space. We mathematically derive all static and stable configurations in final states for a particular but a large set of ...


Rein Robert   2010
The present paper proposes a technical analysis method for extracting information about movement patterning in studies of motor control, based on a cluster analysis of movement kinematics. In a tutorial fashion, data from three different experiments are presented to exemplify and validate the technical method. When applied to three different ...


Foster David   2010
Ensembles of networks are used as null models in many applications. However, simple null models often show much less clustering than their realworld counterparts. In this paper, we study a "biased rewiring model" where clustering is enhanced by means of a fugacity as in the Strauss (or "triangle") model, but ...


Gupta Gunjan   2010
A key application of clustering data obtained from sources such as microarrays, protein mass spectroscopy, and phylogenetic profiles is the detection of functionally related genes. Typically, only a small number of functionally related genes cluster into one or more groups, and the rest need to be ignored. For such situations, ...


Wisener L V   2010
Using the spatial scan statistic with a Bernoulli model, in a comparison of the two most common canine uroliths, calcium oxalate (CaOx) and magnesium ammonium phosphate (struvite) we determined whether there was evidence of spatial and/or temporal clustering of each urolith type based on canine submissions from Ontario to the ...


Bootstrapbased methods for estimating standard errors in Cox's regression analyses of clustered ...
Xiao Yongling   2010
We propose two bootstrapbased methods to correct the standard errors (SEs) from Cox's model for withincluster correlation of rightcensored event times. The clusterbootstrap method resamples, with replacement, only the clusters, whereas the twostep bootstrap method resamples (i) the clusters, and (ii) individuals within each selected cluster, with replacement. In simulations, ...


Molitor John J Department of Epidemiology and Biostatistics, School of Public Health, Imperial College, St Mary's Campus, Norfolk Place, London, UK.   2010
Standard regression analyses are often plagued with problems encountered when one tries to make inference going beyond main effects using data sets that contain dozens of variables that are potentially correlated. This situation arises, for example, in epidemiology where surveys or study questionnaires consisting of a large number of questions ...


Okazaki Naoaki   2010
The ultimate goal of abbreviation management is to disambiguate every occurrence of an abbreviation into its expanded form (concept or sense). To collect expanded forms for abbreviations, previous studies have recognized abbreviations and their expanded forms in parenthetical expressions of biomedical texts. However, expanded forms extracted by abbreviation recognition are ...


Bulatov Aleksandr   2010
In the present communication, we have developed a computational model related to the conception of positional coding via centersofmasses (centroids) of the objects' luminance distributions. The model predictions have been tested by the results of our psychophysical study of geometrical illusion of extent evoked by a modified Brentano figure consisting ...


Knox Craig K   2010
Atomistic molecular dynamics simulations were performed to study hydrated Nafion systems large enough (approximately 2 million atoms, approximately 30 nm box length) to directly observe several hydrophilic domains at the molecular level. These systems consisted of six of the most significant and relevant morphological models of Nafion todate: (1) the ...


Ming Wang   2011
Clustered longitudinal data are often collected as repeated measures on subjects arising in clusters. Examples include periodontal disease study, where the measurements related to the disease status of each tooth are collected over time for each patient, which can be considered as a cluster. For such applications, the number of ...


Bellec Pierre   2010
A variety of methods have been developed to identify brain networks with spontaneous, coherent activity in restingstate functional magnetic resonance imaging (fMRI). We propose here a generic statistical framework to quantify the stability of such restingstate networks (RSNs), which was implemented with kmeans clustering. The core of the method consists ...


Pezzoli Lorenzo   2010
OBJECTIVE: Vaccination programmes targeting disease elimination aim to achieve very high coverage levels (e.g. 95%). We calculated the precision of different clustered lot quality assurance sampling (LQAS) designs in computersimulated surveys to provide local health officers in the field with preset LQAS plans to simply and rapidly assess programmes with ...


Spatiotemporal epidemiology of Campylobacter jejuni enteritis, in an area of Northwest England, ...
Gabriel E   2010
A total of 969 isolates of Campylobacter jejuni originating in the Preston, Lancashire postcode district over a 3year period were characterized using multilocus sequence typing. Recently developed statistical methods and a genetic model were used to investigate temporal, spatial, spatiotemporal and genetic variation in human C. jejuni infections. The analysis ...


Fuchs Susanne   2010
Most theories of prosodic structure postulate at least two phrasal categories above the word level, a minor and a major one. One correlate of phrasal boundary marking is lengthening on the right edge of a phrase. To gain a theory neutral understanding of the nature of prosodic boundaries, a Gaussian ...


Abraham Douglas A   2010
False alarms in active sonar systems are often represented statistically as having a probability density function (PDF) with tails heavier than the traditionally assumed Rayleigh PDF. Distributions such as the Weibull, K, and PoissonRayleigh have been used to represent such nonRayleigh clutter and to derive the associated probabilities of false ...


Kim TaeJoon   2010
We present a novel compressed bounding volume hierarchy (BVH) representation, randomaccessible compressed bounding volume hierarchies (RACBVHs), for various applications requiring random access on BVHs of massive models. Our RACBVH representation is compact and transparently supports random access on the compressed BVHs without decompressing the whole BVH. To support random access ...


Hossain Md Monir   2010
This paper extends the spatial locallikelihood model and the spatial mixture model to the spacetime (ST) domain. For comparison, a standard random effect spacetime (SREST) model is examined to allow evaluation of each model's ability in relation to cluster detection. To pursue this evaluation, we use the ST counterparts of ...


Navlakha Saket   2010
Hierarchical clustering is a popular method for grouping together similar elements based on a distance measure between them. In many cases, annotations for some elements are known beforehand, which can aid the clustering process. We present a novel approach for decomposing a hierarchical clustering into the clusters that optimally match ...


Ioup Juliette W   2010
Several clustering methods are available to group like objects into classes. The K means approach is well established. Both standard and homegrown algorithms have been tested in the following applications. One neural network technique is selforganizing map clustering [T. Kohonen, SelfOrganizing Maps, 2nd ed. Springer, New York (1997)]. Although it ...


Köhn HansFriedrich HF Department of Psychological Sciences, University of Missouri, Columbia, MO 652112500, USA.   2010
The pmedian clustering model represents a combinatorial approach to partition data sets into disjoint, nonhierarchical groups. Object classes are constructed around exemplars, that is, manifest objects in the data set, with the remaining instances assigned to their closest cluster centers. Effective, stateoftheart implementations of pmedian clustering are virtually unavailable in ...


Bruzual A Gustavo   2010
In this paper, I review to what extent we can understand the photometric properties of star clusters, and of lowmass, unresolved galaxies, in terms of populationsynthesis models designed to describe 'simple stellar populations' (SSPs), i.e. groups of stars born at the same time, in the same volume of space and ...


Keller Bettina   2010
The identification of metastable states of a molecule plays an important role in the interpretation of molecular simulation data because the freeenergy surface, the relative populations in this landscape, and ultimately also the dynamics of the molecule under study can be described in terms of these states. We compare the ...


Stoner J A JA Department of Biostatistics and Epidemiology, College of Public Health, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.   2010
Multilevel nested, correlated data often arise in biomedical research. Examples include teeth nested within quadrants in a mouth or students nested within classrooms in schools. In some settings, cluster sizes may be large relative to the number of independent clusters and the degree of correlation may vary across clusters. When ...


Jonsson Malin K B   2010
To improve proarrhythmic predictability of preclinical models, we assessed whether human ventricularlike embryonic stem cellderived cardiomyocytes (hESCCMs) can be selected following a standardized protocol. Also, we quantified their arrhythmogenic response and compared this to a contemporary used rabbit Purkinje fiber (PF) model. Multiple transmembrane action potentials (AP) were recorded from ...


Han XiaoJing   2010
Based on the fact that the kinetic energy of one atom in small cluster still obeys the Boltzmann distribution, a statistical model is developed to predict the time consumed by a small cluster transforming from one isomer to another and is tested by vast molecular dynamics simulations of C(12) isomers ...


Dean Nema   2010
We propose a method for selecting variables in latent class analysis, which is the most common modelbased clustering method for discrete data. The method assesses a variable's usefulness for clustering by comparing two models, given the clustering variables already selected. In one model the variable contributes information about cluster allocation ...


Seiler Michael   2010
We have created a standalone software tool, ConsensusCluster, for the analysis of highdimensional single nucleotide polymorphism (SNP) and gene expression microarray data. Our software implements the consensus clustering algorithm and principal component analysis to stratify the data into a given number of robust clusters. The robustness is achieved by combining ...


Alzate Carlos   2010
A new formulation for multiway spectral clustering is proposed. This method corresponds to a weighted kernel principal component analysis (PCA) approach based on primaldual leastsquares support vector machine (LSSVM) formulations. The formulation allows the extension to outofsample points. In this way, the proposed clustering model can be trained, validated, and ...


Kaupuzs J   2010
A parallel [open multiprocessing (OpenMP)] implementation of the Wolff singlecluster algorithm has been developed and tested for the threedimensional (3D) Ising model. The developed procedure is generalizable to other lattice spin models and its effectiveness depends on the specific application at hand. The applicability of the developed methodology is discussed ...


Ross Michelle E ME Department of Biostatistics, University of Washington, Seattle, WA,   2010
Incidence of myelodysplastic syndromes (MDS) has been described in the United States since its inclusion in the Surveillance, Epidemiology, and End Results program in 2001, and the SeattlePuget Sound region of Washington State has among the highest rates of the registries. In this investigation, we described smallscale incidence patterns of ...


Chen DuanRung   2010
Obesity, one of the most significant health problems now facing developed countries, has been increasing steadily in Taiwan. This study addresses how neighborhood factors affect individual obesity by simultaneously examining individuallevel socioeconomic status and neighborhoodlevel characteristics using a multilevel approach combined with a spatial analysis. The data are from Taiwan's ...


Holliday T W   2010
The proximal femur has long been used to distinguish fossil hominin taxa. Specifically, the genus Homo is said to be characterized by larger femoral heads, shorter femoral necks, and more lateral flare of the greater trochanter than are members of the genera Australopithecus or Paranthropus. Here, a digitizing arm was ...


Shatsky Maxim M Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA.   2010
Biological macromolecules can adopt multiple conformational and compositional states due to structural flexibility and alternative subunit assemblies. This structural heterogeneity poses a major challenge in the study of macromolecular structure using singleparticle electron microscopy. We propose a fully automated, unsupervised method for the threedimensional reconstruction of multiple structural models from ...


The relationship between leadership, teamworking, structure, burnout and attitude to patients on ...
Bowers Len   2011
Conflict (aggression, substance use, absconding, etc.) and containment (coerced medication, manual restraint, etc.) threaten the safety of patients and staff on psychiatric wards. Previous work has suggested that staff variables may be significant in explaining differences between wards in their rates of these behaviours, and that structure (ward organisation, rules ...


Chen ShyiMing   2010
In this paper, we present a new method to predict the Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX) based on fuzzytrend logical relationship groups (FTLRGs). The proposed method divides fuzzy logical relationships into FTLRGs based on the trend of adjacent fuzzy sets appearing in the antecedents of fuzzy logical ...


Wang Fei   2010
Maximum margin clustering (MMC) is a newly proposed clustering method which has shown promising performance in recent studies. It extends the computational techniques of support vector machine (SVM) to the unsupervised scenario. Traditionally, MMC is formulated as a nonconvex integer programming problem which makes it difficult to solve. Several methods ...


Unsupervised white matter fiber clustering and tract probability map generation: applications of ...
Wassermann D D INRIA Sophia AntipolisMediterranée, Odyssée Project Team, 2004 Route des Lucioles, Sophia Antipolis, 06902, France.   2010
With the increasing importance of fiber tracking in diffusion tensor images for clinical needs, there has been a growing demand for an objective mathematical framework to perform quantitative analysis of white matter fiber bundles incorporating their underlying physical significance. This article presents such a novel mathematical framework that facilitates mathematical ...


K?hn Andreas   2010
In explicitly correlated coupledcluster singles and doubles [CCSD(F12)] calculations, the basis set incompleteness error in the double excitations is reduced to such an extent that the error in the HartreeFock energy and the error in the single excitations become important. Using arguments from perturbation theory to systematically truncate the coupledcluster ...


Layton Anita T   2010
A new, regionbased mathematical model of the urine concentrating mechanism of the rat renal inner medulla (IM) was used to investigate the significance of transport and structural properties revealed in recent studies that employed immunohistochemical methods combined with threedimensional computerized reconstruction. The model simulates preferential interactions among tubules and vessels ...


Frades Itziar   2010
Clustering is the unsupervised, semisupervised, and supervised classification of patterns into groups. The clustering problem has been addressed in many contexts and disciplines. Cluster analysis encompasses different methods and algorithms for grouping objects of similar kinds into respective categories. In this chapter, we describe a number of methods and algorithms ...


Jonsson Malin E   2010
Campylobacteriosis is the most frequently reported zoonosis in the EU and the epidemiology of sporadic campylobacteriosis, especially the routes of transmission, is to a great extent unclear. Poultry easily become colonised with Campylobacter spp., being symptomless intestinal carriers. Earlier it was estimated that internationally between 50% and 80% of the ...


Austin Peter C   2010
Multilevel logistic regression models are increasingly being used to analyze clustered data in medical, public health, epidemiological, and educational research. Procedures for estimating the parameters of such models are available in many statistical software packages. There is currently little evidence on the minimum number of clusters necessary to reliably fit ...


Li Ning N Department of Epidemiology and Biostatistics, University of Florida, Gainesville, Florida, United States of   2010
Gene clustering of periodic transcriptional profiles provides an opportunity to shed light on a variety of biological processes, but this technique relies critically upon the robust modeling of longitudinal covariance structure over time. We propose a statistical method for functional clustering of periodic gene expression by modeling the covariance matrix ...


Cooper C Garret   2010
Similarly responsive neurons organize into submillimetersized clusters (domains) across many neocortical areas, notably in Areas V1 and V2 of primate visual cortex. While this clustered organization may arise from wiring minimization or from selforganizing development, it could potentially support important neural computation benefits. Here, we suggest that domain organization offers ...


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