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Full-Text Articles in Physical Sciences and Mathematics

Nbr2 Errata And Comments, Joseph Hilbe Dec 2012

Nbr2 Errata And Comments, Joseph Hilbe

Joseph M Hilbe

Errata and Comments for Negative Binomial Regression, 2nd edition


Piscine Myocarditis Virus (Pmcv) In Wild Atlantic Salmon Salmo Salar, Torstein Tengs Dr. Dec 2012

Piscine Myocarditis Virus (Pmcv) In Wild Atlantic Salmon Salmo Salar, Torstein Tengs Dr.

Dr. Torstein Tengs

Cardiomyopathy syndrome (CMS) is a severe cardiac disease of sea-farmed Atlantic salmon Salmo salar L., but CMS-like lesions have also been found in wild Atlantic salmon. In 2010 a double-stranded RNA virus of the Totiviridae family, provisionally named piscine myocarditis virus (PMCV), was described as the causative agent of CMS. In the present paper we report the first detection of PMCV in wild Atlantic salmon. The study is based on screening of 797 wild Atlantic salmon by real-time RT-PCR. The samples were collected from 35 different rivers along the coast of Norway, and all individuals included in the study were …


Generalized Estimating Equations, Second Edition.Pdf, James W. Hardin, Joseph M.. Hilbe Dec 2012

Generalized Estimating Equations, Second Edition.Pdf, James W. Hardin, Joseph M.. Hilbe

Joseph M Hilbe

Generalized Estimating Equations, Second edition, updates the best-selling previous edition, which has been the standard text on the subject since it was published a decade ago. Combining theory and application, the text provides readers with a comprehensive discussion of GEE and related models. Numerous examples are employed throughout the text, along with the software code used to create, run, and evaluate the models being examined. Stata is used as the primary software for running and displaying modeling output; associated R code is also given to allow R users to replicate Stata examples. Specific examples of SAS usage are provided in …


A Doubling Technique For The Power Method Transformations, Mohan D. Pant, Todd C. Headrick Oct 2012

A Doubling Technique For The Power Method Transformations, Mohan D. Pant, Todd C. Headrick

Mohan Dev Pant

Power method polynomials are used for simulating non-normal distributions with specified product moments or L-moments. The power method is capable of producing distributions with extreme values of skew (L-skew) and kurtosis (L-kurtosis). However, these distributions can be extremely peaked and thus not representative of real-world data. To obviate this problem, two families of distributions are introduced based on a doubling technique with symmetric standard normal and logistic power method distributions. The primary focus of the methodology is in the context of L-moment theory. As such, L-moment based systems of equations are derived for simulating univariate and multivariate non-normal distributions with …


A Pooled Analysis Of Smoking And Colorectal Cancer: Timing Of Exposure And Interactions With Environmental Factors Sep 2012

A Pooled Analysis Of Smoking And Colorectal Cancer: Timing Of Exposure And Interactions With Environmental Factors

Shuo Jiao

Background:Considerable evidence suggests that cigarette smoking is associated with a higher risk of colorectal cancer. What is unclear, however, is the impact of quitting smoking on risk attenuation and whether other risk factors for colorectal cancer modify this association. Methods:We performed a pooled analysis of 8 studies, including 6,796 colorectal cancer cases and 7,770 controls to evaluate the association between cigarette smoking history and colorectal cancer risk, and to investigate potential effect modification by other risk factors. Results:Current smokers (OR=1.26, 95% CI=1.11-1.43) and former smokers (OR=1.18, 95% CI=1.09-1.27), relative to never smokers, showed higher risks of colorectal cancer. Former smokers …


Statistical Methods For Social Network Analysis With Applications In Economics, Carlo Drago Sep 2012

Statistical Methods For Social Network Analysis With Applications In Economics, Carlo Drago

Carlo Drago

No abstract provided.


International Astrostatistics Association, Joseph Hilbe Sep 2012

International Astrostatistics Association, Joseph Hilbe

Joseph M Hilbe

Overview of the history, purpose, Council and officers of the International Astrostatistics Association (IAA)


Prevalence Of Tick Borne Encephalitis Virus In Tick Nymphs In Relation To Climatic Factors On The Southern Coast Of Norway, Torstein Tengs Dr. Aug 2012

Prevalence Of Tick Borne Encephalitis Virus In Tick Nymphs In Relation To Climatic Factors On The Southern Coast Of Norway, Torstein Tengs Dr.

Dr. Torstein Tengs

BACKGROUND

Tick-borne encephalitis (TBE) is among the most important vector borne diseases of humans in Europe and is currently identified as a major health problem in many countries. TBE endemic zones have expanded over the past two decades, as well as the number of reported cases within endemic areas. Multiple factors are ascribed for the increased incidence of TBE, including climatic change. The number of TBE cases has also increased in Norway over the past decade, and the human cases cluster along the southern coast of Norway. In Norway the distribution and prevalence of TBE virus (TBEV) in tick populations …


Global Optimization Of Some Difficult Benchmark Functions By Cuckoo-Host Co-Evolution Meta-Heuristics, Sudhanshu K. Mishra Aug 2012

Global Optimization Of Some Difficult Benchmark Functions By Cuckoo-Host Co-Evolution Meta-Heuristics, Sudhanshu K. Mishra

Sudhanshu K Mishra

This paper proposes a novel method of global optimization based on cuckoo-host co-evaluation. It also develops a Fortran-77 code for the algorithm. The algorithm has been tested on 96 benchmark functions (of which the results of 32 relatively harder problems have been reported). The proposed method is comparable to the Differential Evolution method of global optimization.


An L-Moment-Based Analog For The Schmeiser-Deutsch Class Of Distributions, Todd C. Headrick, Mohan D. Pant Aug 2012

An L-Moment-Based Analog For The Schmeiser-Deutsch Class Of Distributions, Todd C. Headrick, Mohan D. Pant

Mohan Dev Pant

This paper characterizes the conventional moment-based Schmeiser-Deutsch (S-D) class of distributions through the method of L-moments. The system can be used in a variety of settings such as simulation or modeling various processes. A procedure is also described for simulating S-D distributions with specified L-moments and L-correlations. The Monte Carlo results presented in this study indicate that the estimates of L-skew, L-kurtosis, and L-correlation associated with the S-D class of distributions are substantially superior to their corresponding conventional product-moment estimators in terms of relative bias—most notably when sample sizes are small.


諸外国のデータエディティング及び混淆正規分布モデルによる多変量外れ値検出法についての研究(高橋将宜、選択的エディティング、セレクティブエディティング), Masayoshi Takahashi Aug 2012

諸外国のデータエディティング及び混淆正規分布モデルによる多変量外れ値検出法についての研究(高橋将宜、選択的エディティング、セレクティブエディティング), Masayoshi Takahashi

Masayoshi Takahashi

No abstract provided.


Technical Factors Utilised By Elite Archers: Towards Setting An Agenda For Archery, Andrew J. Callaway, Shelley A. Broomfield Jul 2012

Technical Factors Utilised By Elite Archers: Towards Setting An Agenda For Archery, Andrew J. Callaway, Shelley A. Broomfield

Andrew J Callaway

Archery, in one form or another, has been around for thousands of years yet research into what makes an archer 'good' is still in its infancy. There are several variations over bow type and different competitions which can be competed, previous works have focused on Recurve (Olympic) bow types whilst Compound have generally been ignored. Research in the area has tended to focus on muscle activation patterns using Electromyography (EMG) and aiming based studies, where generally scores are used as a factor to correlate to.

AIM: The aim of this research is to offer a development from the use of …


Data Mining Of Portable Eeg Brain Wave Signals For Sports Performance Analysis: An Archery Case Study, Matthew Casey, Alan Yau, Andrew J. Callaway, Keith Barfoot Jul 2012

Data Mining Of Portable Eeg Brain Wave Signals For Sports Performance Analysis: An Archery Case Study, Matthew Casey, Alan Yau, Andrew J. Callaway, Keith Barfoot

Andrew J Callaway

No abstract provided.


A Strain Of Piscine Myocarditis Virus (Pmcv) Infecting Argentina Silus (Ascanius), Torstein Tengs Dr. Jul 2012

A Strain Of Piscine Myocarditis Virus (Pmcv) Infecting Argentina Silus (Ascanius), Torstein Tengs Dr.

Dr. Torstein Tengs

No abstract.


Towards Better Estimation Of Jump Diffusion Models, Richard H. Serlin Jul 2012

Towards Better Estimation Of Jump Diffusion Models, Richard H. Serlin

Richard H. Serlin

I discuss in-depth modern techniques for the estimation of Jump Diffusion models with suggestions for improvements. There is a heavy focus on intuition. I also point out examples of the use of improper techniques (biased and inconsistent) in the top tier finance literature.


Targeted Maximum Likelihood Estimation For Dynamic Treatment Regimes In Sequential Randomized Controlled Trials, Paul Chaffee, Mark J. Van Der Laan Jun 2012

Targeted Maximum Likelihood Estimation For Dynamic Treatment Regimes In Sequential Randomized Controlled Trials, Paul Chaffee, Mark J. Van Der Laan

Paul H. Chaffee

Sequential Randomized Controlled Trials (SRCTs) are rapidly becoming essential tools in the search for optimized treatment regimes in ongoing treatment settings. Analyzing data for multiple time-point treatments with a view toward optimal treatment regimes is of interest in many types of afflictions: HIV infection, Attention Deficit Hyperactivity Disorder in children, leukemia, prostate cancer, renal failure, and many others. Methods for analyzing data from SRCTs exist but they are either inefficient or suffer from the drawbacks of estimating equation methodology. We describe an estimation procedure, targeted maximum likelihood estimation (TMLE), which has been fully developed and implemented in point treatment settings, …


Comparing Years Of Healthy Life, Measured In 16 Ways, For Normal Weight And Overweight Older Adults, Paula Diehr Jun 2012

Comparing Years Of Healthy Life, Measured In 16 Ways, For Normal Weight And Overweight Older Adults, Paula Diehr

Paula Diehr

Introduction. The traditional definitions of overweight and obesity are not age specific, even though the relationship of weight to mortality is different for older adults. Effects of adiposity on aspects of health beside mortality have not been well investigated. Methods. We calculated the number of years of healthy life (YHL) in the 10 years after baseline, for 5,747 older adults. YHL was defined in 16 different ways. We compared Normal and Overweight persons, classified either by bodymass index (BMI) or by waist circumference (WC). Findings. YHL for Normal and Overweight persons differed significantly in 25% of the comparisons, of which …


On The Existence Of Constant Accrual Rates In Clinical Trials And Direction For Future Research, Byron J. Gajewski, Stephen D. Simon, Susan E. Carslon Jun 2012

On The Existence Of Constant Accrual Rates In Clinical Trials And Direction For Future Research, Byron J. Gajewski, Stephen D. Simon, Susan E. Carslon

Byron J Gajewski

Many clinical trials fall short of their accrual goals. This can be avoided with accurate accrual prediction tools. Past researchers provide important methodological alternative models for predicting accrual in clinical trials. One model allows for slow accrual at the start of the study, which eventually reaches a threshold. A simpler model assumes a constant rate of accrual. A comparison has been attempted but we wish to point out some important considerations when comparing these two models. In fact, we can examine the reasonableness of a constant accrual assumption (simpler model) which had data 239 days into a three- year study. …


Glme3_Ado_Do_Files, Joseph Hilbe May 2012

Glme3_Ado_Do_Files, Joseph Hilbe

Joseph M Hilbe

GLME3 ado and do files (116 in total)


Glme3 Data And Adodo Files, Joseph Hilbe May 2012

Glme3 Data And Adodo Files, Joseph Hilbe

Joseph M Hilbe

A listing of Data Sets and Stata software commands and do files in GLME3 book


Quantification Of Piscine Reovirus (Prv) At Different Stages Of Atlantic Salmon Salmo Salar Production, Torstein Tengs Dr. May 2012

Quantification Of Piscine Reovirus (Prv) At Different Stages Of Atlantic Salmon Salmo Salar Production, Torstein Tengs Dr.

Dr. Torstein Tengs

The newly described piscine reovirus (PRV) appears to be associated with the development of heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon Salmo salar L. PRV seems to be ubiquitous among fish in Norwegian salmon farms, but high viral loads and tissue distribution support a causal relationship between virus and disease. In order to improve understanding of the distribution of PRV in the salmon production line, we quantified PRV by using real-time PCR on heart samples collected at different points in the life cycle from pre-smolts to fish ready for slaughter. PRV positive pre-smolts were found in about …


A Method For Simulating Nonnormal Distributions With Specified L-Skew, L-Kurtosis, And L-Correlation, Todd C. Headrick, Mohan D. Pant May 2012

A Method For Simulating Nonnormal Distributions With Specified L-Skew, L-Kurtosis, And L-Correlation, Todd C. Headrick, Mohan D. Pant

Mohan Dev Pant

This paper introduces two families of distributions referred to as the symmetric κ and asymmetric κL-κR distributions. The families are based on transformations of standard logistic pseudo-random deviates. The primary focus of the theoretical development is in the contexts of L-moments and the L-correlation. Also included is the development of a method for specifying distributions with controlled degrees of L-skew, L-kurtosis, and L-correlation. The method can be applied in a variety of settings such as Monte Carlo studies, simulation, or modeling events. It is also demonstrated that estimates of L-skew, L-kurtosis, and L-correlation are superior to conventional product-moment estimates of …


Simulating Non-Normal Distributions With Specified L-Moments And L-Correlations, Todd C. Headrick, Mohan D. Pant May 2012

Simulating Non-Normal Distributions With Specified L-Moments And L-Correlations, Todd C. Headrick, Mohan D. Pant

Mohan Dev Pant

This paper derives a procedure for simulating continuous non-normal distributions with specified L-moments and L-correlations in the context of power method polynomials of order three. It is demonstrated that the proposed procedure has computational advantages over the traditional product-moment procedure in terms of solving for intermediate correlations. Simulation results also demonstrate that the proposed L-moment-based procedure is an attractive alternative to the traditional procedure when distributions with more severe departures from normality are considered. Specifically, estimates of L-skew and L-kurtosis are superior to the conventional estimates of skew and kurtosis in terms of both relative bias and relative standard error. …


Decomposition Of High Frequency Data In Components: Visualization And Interpretative Models, Carlo Drago May 2012

Decomposition Of High Frequency Data In Components: Visualization And Interpretative Models, Carlo Drago

Carlo Drago

No abstract provided.


A Comparative Study Of Trends In Globalization Using Different Synthetic Indicators, Sudhanshu K. Mishra Apr 2012

A Comparative Study Of Trends In Globalization Using Different Synthetic Indicators, Sudhanshu K. Mishra

Sudhanshu K Mishra

Using the KOF data at the annual level, we construct ten different composite indices for comparing the extent of globalization of 131 countries for eleven years, 1999-2009. We compare the different indices of globalization among themselves and also with the Dreher-KOF index of globalization and find that among the different indices the Dreher-Chebyshev index is the most representative one. Among the countries, we concentrate on the trends in globalization of India and her neighboring countries, Bangladesh, China, and Pakistan.


A Maximum Entropy Perspective Of Pena’S Synthetic Indicators, Sudhanshu K. Mishra Apr 2012

A Maximum Entropy Perspective Of Pena’S Synthetic Indicators, Sudhanshu K. Mishra

Sudhanshu K Mishra

This paper uses mixed combinatorial-cum-real particle swarm method to obtain a heuristically optimal order in which the constituent variables can be arranged so as to yield some generalized maximum entropy synthetic indicators that represent the constituent variables in the best information-theoretic sense. It may help resolve the arbitrariness and indeterminacy of Pena’s method of construction of a synthetic indicator which at present is very sensitive to the order in which the constituent variables (whose linear aggregation yields the synthetic indicator) are arranged.


Joint Generalized Models For Multi-Dimensional Outcomes: A Case Study Of Neuroscience Data From Multi-Modalities, Xiao-Feng Wang Apr 2012

Joint Generalized Models For Multi-Dimensional Outcomes: A Case Study Of Neuroscience Data From Multi-Modalities, Xiao-Feng Wang

Xiaofeng Wang

This paper is motivated from the analysis of neuroscience data in a study of neural and muscular mechanisms of muscle fatigue. Multidimensional outcomes of different natures were obtained simultaneously from multiple modalities, including handgrip force, electromyography (EMG), and functional magnetic resonance imaging (fMRI). We first study individual modeling of the univariate response depending on its nature. A mixed-effects beta model and a mixed-effects simplex model are compared for modeling the force/EMG percentages. A mixed-effects negative-binomial model is proposed for modeling the fMRI counts. Then, I present a joint modeling approach to model the multidimensional outcomes together, which allows us to …


Characterization Of Gene–Environment Interactions For Colorectal Cancer Susceptibility Loci Apr 2012

Characterization Of Gene–Environment Interactions For Colorectal Cancer Susceptibility Loci

Shuo Jiao

Genome-wide association studies (GWAS) have identified more than a dozen loci associated with colorectal cancer (CRC) risk. Here, we examined potential effect-modification between single-nucleotide polymorphisms (SNP) at 10 of these loci and probable or established environmental risk factors for CRC in 7,016 CRC cases and 9,723 controls from nine cohort and case–control studies. We used meta-analysis of an efficient empirical-Bayes estimator to detect potential multiplicative interactions between each of the SNPs [rs16892766 at 8q23.3 (EIF3H/UTP23), rs6983267 at 8q24 (MYC), rs10795668 at 10p14 (FLJ3802842), rs3802842 at 11q23 (LOC120376), rs4444235 at 14q22.2 (BMP4), rs4779584 at 15q13 (GREM1), rs9929218 at 16q22.1 (CDH1), rs4939827 …


Powerful Cocktail Methods For Detecting Genome-Wide Gene-Environment Interaction, Li Hsu, Shuo Jiao, James Y. Dai, Carolyn M. Hutter, Ulrike Peters, Charles Kooperberg Apr 2012

Powerful Cocktail Methods For Detecting Genome-Wide Gene-Environment Interaction, Li Hsu, Shuo Jiao, James Y. Dai, Carolyn M. Hutter, Ulrike Peters, Charles Kooperberg

Shuo Jiao

Identifying gene and environment interaction (G × E) can provide insights into biological networks of complex diseases, identify novel genes that act synergistically with environmental factors, and inform risk prediction. However, despite the fact that hundreds of novel disease-associated loci have been identified from genome-wide association studies (GWAS), few G×Es have been discovered. One reason is thatmost studies are underpowered for detecting these interactions. Several new methods have been proposed to improve power for G × E analysis, but performance varies with scenario. In this article, we present a module-based approach to integrating various methods that exploits each method’s most …


A Note On Construction Of Heuristically Optimal Pena’S Synthetic Indicators By The Particle Swarm Method Of Global Optimization, Sudhanshu K. Mishra Mar 2012

A Note On Construction Of Heuristically Optimal Pena’S Synthetic Indicators By The Particle Swarm Method Of Global Optimization, Sudhanshu K. Mishra

Sudhanshu K Mishra

Pena’s method of construction of a synthetic indicator is very sensitive to the order in which the constituent variables (whose linear aggregation yields the synthetic indicator) are arranged. Due to this, Pena’s method can at present give only an arbitrary synthetic indicator whose representativeness is indeterminate and uncertain, especially when the number of constituent variables is not very small. This paper uses discrete global optimization method based on the Particle Swarms to obtain a heuristically optimal order in which the constituent variables can be arranged so as to yield Pena’s synthetic indicator that maximizes the minimal absolute (or squared) correlation …