Digital Commons Network^™

Mvn: An R Package For Assessing Multivariate Normality, Selcuk Korkmaz, Dincer Goksuluk, Gokmen Zararsiz

The R Journal

Assessing the assumption of multivariate normality is required by many parametric multivariate statistical methods, such as MANOVA, linear discriminant analysis, principal component analysis, canonical correlation, etc. It is important to assess multivariate normality in order to proceed with such statistical methods. There are many analytical methods proposed for checking multivariate normality. However, deciding which method to use is a challenging process, since each method may give different results under certain conditions. Hence, we may say that there is no best method, which is valid under any condition, for normality checking. In addition to numerical results, it is very useful to …

Ngspatial: A Package For Fitting The Centered Autologistic And Sparse Spatial Generalized Linear Mixed Models For Areal Data, John Hughes

The R Journal

Two important recent advances in areal modeling are the centered autologistic model and the sparse spatial generalized linear mixed model (SGLMM), both of which are reparameterizations of traditional models. The reparameterizations improve regression inference by alleviating spatial confounding, and the sparse SGLMM also greatly speeds computing by reducing the dimension of the spatial random effects. Package ngspatial (’ng’ = non-Gaussian) provides routines for fitting these new models. The package supports composite likelihood and Bayesian inference for the centered autologistic model, and Bayesian inference for the sparse SGLMM.

Coordinate-Based Meta-Analysis Of Fmri Studies With R, Andrea Stocco

The R Journal

This paper outlines how to conduct a simple meta-analysis of neuroimaging foci of activation in R. In particular, the first part of this paper reviews the nature of fMRI data, and presents a brief overview of the existing packages that can be used to analyze fMRI data in R. The second part illustrates how to handle fMRI data by showing how to visualize the results of different neuroimaging studies in a so-called orthographic view, where the spatial distribution of the foci of activation from different fMRI studies can be inspected visually.

Functional MRI (fMRI) is one of the most important …

Bshazard: A Flexible Tool For Nonparametric Smoothing Of The Hazard Function, Paola Rebora, Agus Salim, Marie Reilly

The R Journal

The hazard function is a key component in the inferential process in survival analysis and relevant for describing the pattern of failures. However, it is rarely shown in research papers due to the difficulties in nonparametric estimation. We developed the bshazard package to facilitate the computation of a nonparametric estimate of the hazard function, with data-driven smoothing. The method accounts for left truncation, right censoring and possible covariates. B-splines are used to estimate the shape of the hazard within the generalized linear mixed models frame work. Smoothness is controlled by imposing an autoregressive structure on the baseline hazard coefficients. This …

Prinsimp, Jonathan Zhang, Nancy Heckman, Davor Cubranic, Joel G. Kingsolver, Travis Gaydos, J.S. Marron

The R Journal

Principal Components Analysis (PCA) is a common way to study the sources of variation in a high-dimensional data set. Typically, the leading principal components are used to understand the variation in the data or to reduce the dimension of the data for subsequent analysis. The remaining principal components are ignored since they explain little of the variation in the data. However, the space spanned by the low variation principal components may contain interesting structure, structure that PCA cannot find. Prinsimp is an R package that looks for interesting structure of low variability. “Interesting” is defined in terms of a simplicity …

Phaser: An R Package For Phase Plane Analysis Of Autonomous Ode Systems, Michael J. Grayling

The R Journal

When modelling physical systems, analysts will frequently be confronted by differential equations which cannot be solved analytically. In this instance, numerical integration will usually be the only way forward. However, for autonomous systems of ordinary differential equations (ODEs) in one or two dimensions, it is possible to employ an instructive qualitative analysis foregoing this requirement, using so-called phase plane methods. Moreover, this qualitative analysis can even prove to be highly useful for systems that can be solved analytically, or will be solved numerically anyway. The package phaseR allows the user to perform such phase plane analyses: determining the stability of …

Taming Pitchf/X Data With Xml2r And Pitchrx, Carson Sievert

The R Journal

XML2R is a framework that reduces the effort required to transform XML content into tables in a way that preserves parent to child relationships. pitchRx applies XML2R’s grammar for XML manipulation to Major League Baseball Advanced Media (MLBAM)’s Gameday data. With pitchRx, one can easily obtain and store Gameday data in a remote database. The Gameday website hosts a wealth of XML data, but perhaps most interesting is PITCHf/x. Among other things, PITCHf/x data can be used to recreate a baseball’s flight path from a pitcher’s hand to home plate. With pitchRx, one can easily create animations …

Applying Spartan To Understand Parameter Uncertainty In Simulations, Kieran Alden, Mark Read, Paul S. Andrews, Jon Timmis, Mark Coles

The R Journal

In attempts to further understand the dynamics of complex systems, the application of computer simulation is becoming increasingly prevalent. Whereas a great deal of focus has been placed in the development of software tools that aid researchers develop simulations, similar focus has not been applied in the creation of tools that perform a rigorous statistical analysis of results generated through simulation: vital in understanding how these results offer an insight into the captured system. This encouraged us to develop spartan, a package of statistical techniques designed to assist researchers in understanding the relationship between their simulation and the real system. …

In Memory Of Margaret Triplett

Nebraska Bird Review

The NOU lost a longtime member in Kearney on August 7, 2014, when Margaret Sealing Triplett died.

Summary Of Raptor Banding Efforts At Hitchcock Nature Center, Fall 2014, Jerry Toll

Nebraska Bird Review

The 2014 season was by far the most unusual and frustrating season since the inception of raptor banding and hawk watch at the Hitchcock Nature Center in Pottawatomie County, Iowa, just north of Crescent. Banding diurnal raptors commenced on September 7th on schedule. The month of September was typical as far as capture rates and weather systems, although we were stymied somewhat by the lack of availability of European Starlings for lure birds. House Sparrows proved a nearly adequate substitute.

During the peak period of October, weather systems that drive diurnal raptor migration worked against monitoring efforts by forcing migration …

First Documented Nest Of Northern Saw-Whet Owl In Nebraska, Wayne J. Mollhoff

Nebraska Bird Review

Northern Saw-whet Owl was added to our avifauna with a list prepared by Taylor and Van Vleet (1889). The first suggestion of breeding was a second-hand report included in a paper presented at the first meeting of the Nebraska Ornithologists' Union in 1899 by M. A. Carriker, Jr., who "was told of a set of five eggs collected near Nebraska City about seven years ago" (1900), but which included no other details. At the next meeting, Bruner (1901) cited that report to include the species on a list of birds that breed in the state. Bruner, Swenk, and Walcott later …

Nebraska Bird Review (December 2014) 82(4), Whole Issue

Nebraska Bird Review

Fall Field Report, August–November 2014 ... 150

Holdrege Fall Field Days … 181

Summary of Raptor Banding Efforts at Hitchcock Nature Center, Fall 2014 ... 186

First Documented Nest of Northern Saw-whet Owl in Nebraska ... 189

In Memory of Margaret Triplett … 194

Index to Volume 82 … 195

Subscription and Organization Information ... 207

The Role Of Ceramides In Mediating Endotoxin-Induced Mitochondrial Disruption, Melissa Ellen Hansen

Theses and Dissertations

Ceramides are sphingolipids that serve as important second messengers in an increasing number of stress-induced pathways. Ceramide has long been known to affect the mitochondria, altering both morphology and physiology. Lipopolysaccharide (LPS) is a prevalent circulating inflammatory agent in obesity, potentially mediating some of the pathologies associated with weight gain. Given previous findings of TLR4-mediated ceramide accrual and ceramide-mediated mitochondrial disruption, we questioned whether ceramide is necessary for LPS-induced mitochondrial disruption. We found that LPS treatment increased gene transcript levels of ceramide synthesis enzymes and mitochondrial fission proteins and increased ceramide content in cultured myotubes and in mouse tissue. Mitochondrial …

Teachers' Curricular Reasoning And Mkt In The Context Of Algebra And Statistics, Kolby J. Gadd

Theses and Dissertations

This study investigates 7th grade teachers' curricular reasoning and MKT in algebra and statistics. Although the use of curriculum materials and MKT both influence the quality of mathematics instruction, no relationship between teachers' curricular reasoning and MKT was found. Further, teachers' curricular reasoning across algebra and statistics was very similar despite differences in these fields and differences in MKT. A model for thinking about the knowledge needed to provide high quality instruction is proposed by considering the role of curricular reasoning and MKT in instruction.

Pedagogical And Ekphrastic Elements In The Story Of The Predestined Pilgrim And His Brother Reprobate By Father Alexandre De Gusm, M Cecilia Fischer

Theses and Dissertations

The object of this thesis is to analyze the presence of the pedagogical ekphrastic elements in the novel The Story of The Predestined Pilgrim and his Brother Reprobate by Father Alexandre de Gusmmão. In the past this novel has been an obscure masterpiece outside the circle of those who study early Portuguese language works. In the last half century there has been a crescendo of the study of this novel as more scholars have taken an interest in the pilgrimage motif and in particular using this novel in comparative literature. A monumental contribution to bring this novel out of obscurity …

Compact Antennas And Arrays For Unmanned Air Systems, James Arthur Eck

Theses and Dissertations

A simple and novel dual-CP printed antenna is modelled and measured. The patch antennais small and achieves a low axial ratio without quadrature feeding. The measured pattern showsaxial ratio pattern squinting over frequency. Possible methods of improving the individual element are discussed, as well as an array technique for improving the axial ratio bandwidth. Three endfire printed antenna structures are designed, analyzed, and compared. The comparison includes an analysis of costs of production for the antenna structures in addition to their performance parameters. This analysis concludes that cost of materials primarily reduces the size of antennas for a given gain …

Replication And Knowledge Production In Empirical Software Engineering Research, Jonathan L. Krein

Theses and Dissertations

Although replication is considered an indispensable part of the scientific method in software engineering, few replication studies are published each year. The rate of replication, however, is not surprising given that replication theory in software engineering is immature. Not only are replication taxonomies varied and difficult to reconcile, but opinions on the role of replication contradict. In general, we have no clear sense of how to build knowledge via replication, particularly given the practical realities of our research field. Consequently, most replications in software engineering yield little useful information. In particular, the vast majority of external replications (i.e., replications performed …

Is A Viable Theistic Program Of Psychological Research Possible?, Michael Zhang

Theses and Dissertations

This thesis explores whether a viable theistic program of psychological research is possible. The importance of this exploration has to do with naturalism's monopoly on psychological science, inasmuch as naturalism prevents other worldviews from competing fairly in psychology's scientific marketplace by controlling the criteria of psychological science. Because theism is naturalism's most complete rival, considering theism's scientific potential in psychology is crucial to dismantling naturalism's monopoly. Contrary to conventional wisdom, theism encompasses a unique set of understandings about the natural events that constitute the discipline of psychology. Therefore, a robust scientific conception of theism would change how psychological researchers understand …

The Existence Of A Discontinuous Homomorphism Requires A Strong Axiom Of Choice, Michael Steven Andersen

Theses and Dissertations

Conner and Spencer used ultrafilters to construct homomorphisms between fundamental groups that could not be induced by continuous functions between the underlying spaces. We use methods from Shelah and Pawlikowski to prove that Conner and Spencer could not have constructed these homomorphisms with a weak version of the Axiom of Choice. This led us to define and examine a class of pathological objects that cannot be constructed without a strong version of the Axiom of Choice, which we call the class of inscrutable objects. Objects that do not need a strong version of the Axiom of Choice are scrutable. We …

Microchip Thermal Gradient Gas Chromatography, Anzi Wang

Theses and Dissertations

Although the airbath oven is a reliable heating method for gas chromatography (GC), resistive heating is needed for higher analytical throughput and on-site chemical analysis because of size, heating rate and power requirements. In the last thirty years, a variety of resistive heating methods were developed and implemented for both benchtop and portable GC systems. Although fast heating rates and low power consumption have been achieved, losses in column efficiency and resolution, complex construction processes and difficulties experienced in recovering damaged columns have also become problematic for routine use of resistively heated columns. To solve these problems, a new resistively …

Cheatgrass Die-Off Phenomena: What Are The Short And Long Term Recovery Factors Of Bromus Tectorum Stand Failure?, Joshua Alan Nicholson

Theses and Dissertations

Observations of Bromus tectorum L. (cheatgrass or downy brome) monocultures have shown that populations are susceptible to stand die-off or replacement failures. Die-offs, where the seed bank from the previous year fails to emerge, occurs in cheatgrass stands and it is unclear the trigger or cause. The fungus Fusarium has been identified in plant and seed samples from die-offs and may drive die-off activity through pathogenicity. Die-off recovery may take several years but cheatgrass populations eventually reestablish. The purpose of our study was to determine whether Fusarium is a potential player in a die-off, and understand how die-offs recover after …

The Multidimensional Quality Metric (Mqm) Framework: A New Framework For Translation Quality Assessment, Valerie Ruth Mariana

Theses and Dissertations

This document is a supplement to the article entitled “The Multidimensional Quality Metric (MQM) Framework: A New Framework for Translation Quality Assessment”, which has been acepted for publication in the upcoming January volume of JoSTrans, the Journal of Specialized Translation. The article is a coauthored project between Dr. Alan K. Melby, Dr. Troy Cox and myself. In this document you will find a preface describing the process of writing the article, an annotated bibliography of sources consulted in my research, a summary of what I learned, and a conclusion that considers the future avenues opened up by this research. Our …

Conscience And Context In Eastman Johnson's The Lord Is My Shepherd, Amanda Melanie Slater

Theses and Dissertations

This thesis considers the experiences that motivated the creation of an 1863 painting by American artist Eastman Johnson entitled The Lord is My Shepherd. An examination of the painting—which depicts a black man reading a Bible—reveals multiple artistic, social, political, and spiritual influences. Created in the midst of the American Civil War, the painting's inspiration derived from Johnson's New England childhood, training in Europe, encounters with the Transcendentalist movement, and his abolitionist views. As a result, The Lord is My Shepherd is a culminating work in Johnson's oeuvre that was prompted by years of experience and observations in an age …

Framework To Implement Authentication, Authorization And Secure Communications In A Multiuser Collaborative Cax Environment, Francis Mensah

Theses and Dissertations

Computer Aided Design (CAD) applications have historically been based on a single user per application architecture. Although this architecture is still popular to date, it does have several drawbacks. First of all the single user CAD architecture inhibits a concurrent engineering design process where several designers can work on the same model simultaneously. This limitation introduces time inefficiency especially when a project involves geographically dispersed designers. A solution to these drawbacks could be a transition from the traditional single user CAD architecture to a multiuser collaborative architecture. Advances in computer networking technologies, especially relating to the Internet, have provided the …

Determining The Reliability Of An Early Expository Comprehension Assessment, Tammie Harding

Theses and Dissertations

This study investigated the reliability of the revised Early Expository Comprehension Assessment (EECA), a measure that looked at preschoolers' comprehension of expository text. Thirty-seven preschool children between the ages of four and five were administered two comparable versions of the measure by two examiners. Scoring procedures were created and the protocols were scored and compared for reliability. The data was analyzed using a mixed models Analysis of Variance for repeated measures and a maximum likelihood estimate of variance components. Results from the analysis showed that version and order had no significant effect on three of the response task scores (Purpose …

Fuel Response To Mechanical Mastication Of Pinyon-Juniper Woodlands In Utah, Alan Wyatt Shakespear

Theses and Dissertations

Pinyon-juniper woodland encroachment threatens ecosystem function and diversity on sagebrush steppe. Decreased fire frequency likely favors proliferation of pinyon-juniper woodlands and subsequent decline in desirable understory species. Increased tree cover produces hazardous canopy fuel loads that contribute to severe crown fires and threaten life and property at the wildland-urban-interface. Mechanical mastication converts large canopy fuels into small woody debris, altering wildfire dynamics from a potential crown fire to a more controllable surface fire. We measured fuel loading and cover on untreated, masticated, and masticated + burned treatments on 30-m transects within 30 X 33-m subplots, representing 45 different sites throughout …

Characterization Of Smoothness In Wrist Rotations, Layne Hancock Salmond

Theses and Dissertations

Smoothness is a hallmark of healthy movement and has the potential to be used as a marker of recovery in rehabilitation settings. While much past research has focused on shoulder and elbow movements (reaching), little is known about movements of the wrist despite its importance in everyday life and its impairment in many neurological and biomechanical disorders. Our current lack of knowledge regarding wrist movement prevents us from improving current models, diagnosis, and treatment of wrist disorders. In particular, while movement smoothness is a well-known characteristic of reaching movements and may potentially be used to diagnose and monitor recovery from …

Fire And Ungulate Herbivory Differentially Affect The Sexual Reproduction Of Generalist And Specialist Pollinated Plants, Andrew Hollis Lybbert

Theses and Dissertations

Currently the size and frequency of wildfires are increasing at a global scale, including arid ecosystems that exhibit great sensitivity to disturbance. Fire effects on plant pollination and reproductive success in deserts are largely unknown. Plant dependence on animal pollinators for reproduction can increase the risk of reproductive failure if pollination services are hindered or lost. Species that depend on few taxonomically related pollinator species are expected to be most negatively affected by disturbances that disrupt pollination interactions. To assess fire and isolation effects on reproductive success in desert plant communities, and how wildfire influences the pollination success of generalist …

Investigaciónn De Actitudes Sociolingüísticas Hacia El Valenciano Y El Castellanoen Agost, José Manuel Hernández Gonzalez

Theses and Dissertations

This thesis investigates the attitudes of the inhabitants of Agost towards Castilian and Valencian Catalan. Data were collected by means of a questionnaire distributed among a representative sample of Agostenses between April and June 2013 and analyzed according to three independent variables: sex, age and education. It was hypothesized that attitudes would covary with these variables and, in general, this proved to be the case.

A Covering System With Minimum Modulus 42, Tyler Owens

Theses and Dissertations

We construct a covering system whose minimum modulus is 42. This improves the previous record of 40 by P. Nielsen.