Physical Sciences and Mathematics Commons^™

Scholarships, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.

A Graphical Eda Tool With Ggplot2: Brinton, Pere Millán-Martínez, Ramon Oller

The R Journal

We present brinton package, which we developed for graphical exploratory data analysis in R. Based on ggplot2, gridExtra and rmarkdown, brinton package introduces wideplot() graphics for exploring the structure of a dataset through a grid of variables and graphic types. It also introduces longplot() graphics, which present the entire catalog of available graphics for representing a particular variable using a grid of graphic types and variations on these types. Finally, it introduces the plotup() function, which complements the previous two functions in that it presents a particular graphic for a specific variable of a dataset. This set of functions is …

Nts: An R Package For Nonlinear Time Series Analysis, Xialu Liu, Rong Chen, Ruey Tsay

The R Journal

Linear time series models are commonly used in analyzing dependent data and in forecasting. On the other hand, real phenomena often exhibit nonlinear behavior and the observed data show nonlinear dynamics. This paper introduces the R package NTS that offers various computational tools and nonlinear models for analyzing nonlinear dependent data. The package fills the gaps of several outstanding R packages for nonlinear time series analysis. Specifically, the NTS package covers the implementation of threshold autoregressive (TAR) models, autoregressive conditional mean models with exogenous variables (ACMx), functional autoregressive models, and state-space models. Users can also evaluate and compare the performance …

Aquadtree: An R Package For Quadtree Anonymization Of Point Data, Raymond Lagonigro, Ramon Oller, Joan Carles Martori

The R Journal

The demand for precise data for analytical purposes grows rapidly among the research community and decision makers as more geographic information is being collected. Laws protecting data privacy are being enforced to prevent data disclosure. Statistical institutes and agencies need methods to preserve confidentiality while maintaining accuracy when disclosing geographic data. In this paper we present the AQuadtree package, a software intended to produce and deal with official spatial data making data privacy and accuracy compatible. The lack of specific methods in R to anonymize spatial data motivated the development of this package, providing an automatic aggregation tool to anonymize …

Six Years Of Shiny In Research: Collaborative Development Of Web Tools In R, Peter Kasprzak, Lachlan Mitchell, Olena Kravchuk, Andy Timmins

The R Journal

The use of Shiny in research publications is investigated over the six and a half years since the appearance of this popular web application framework for R, which has been utilised in many varied research areas. While it is demonstrated that the complexity of Shiny applications is limited by the background architecture, and real security concerns exist for novice app developers, the collaborative benefits are worth attention from the wider research community. Shiny simplifies the use of complex methodologies for people of different specialities, at the level of proficiency appropriate for the end user. This enables a diverse community of …

Assembling Pharmacometric Datasets In R: The Puzzle Package, Mario González-Sales, Olivier Barrière, Pierre Olivier Tremblay, Guillaume Bonnefois, Julie Desrochers, Fahima Nekka

The R Journal

Pharmacometric analyses are integral components of the drug development process. The core of each pharmacometric analysis is a dataset. The time required to construct a pharmacometrics dataset can sometimes be higher than the effort required for the modeling per se. To simplify the process, the puzzle R package has been developed aimed at simplifying and facilitating the time consuming and error prone task of assembling pharmacometrics datasets.

Puzzle consist of a series of functions written in R. These functions create, from tabulated files, datasets that are compatible with the formatting requirements of the gold standard non-linear mixed effects modeling …

The Prairie Naturalist, Vol. 52, Issue 2, December 2020

The Prairie Naturalist

Comparing Native Bee Communities on Reconstructed and Remnant Prairie in Missouri • Joseph LaRose, Elisabeth B. Webb, and Deborah Finke

Patterns and Potential Causes of Changing Winter Bird Distributions in South Dakota • David L. Swanson, Reza Goljani Amipkhiz, and Mark D. Dixon

Greater prairie-chickens and sharp-tailed grouse have similarly high nest survival in the Nebraska Sandhills • Larkin A. Powell, Walter H. Schacht, Julia P. Ewalt, and Katie R. McCollum

Captive Ring-necked Pheasant Response to Very High Experimental Doses of Lead • Travis J. Runia and Alex J. Solem

Trends in a Greater Prairie Chicken Population Established by Translocation …

Changes On Cran, Kurt Hornik, Uwe Ligges, Achim Zeileis

The R Journal

In the past 4 months, 818 new packages were added to the CRAN package repository. 100 packages were archived and 248 were archived. The following shows the growth of the number of active packages in the CRAN package repository

R Foundation News, Torsten Hothorn

The R Journal

Membership fees and donations received between 2020-09-09 and 2021-01-28.

Rngforgpd: An R Package For Generation Of Univariate And Multivariate Generalized Poisson Data, Hesen Li, Hakan Demirtas, Ruizhe Chen

The R Journal

This article describes the R package RNGforGPD, which is designed for the generation of univariate and multivariate generalized Poisson data. Some illustrative examples are given, the utility and functionality of the package are demonstrated; and its performance is assessed via simulations that are devised around both artificial and real data.

Species Distribution Modeling Using Spatial Point Processes: A Case Study Of Sloth Occurrence In Costa Rica, Paula Moraga

The R Journal

Species distribution models are widely used in ecology for conservation management of species and their environments. This paper demonstrates how to fit a log-Gaussian Cox process model to predict the intensity of sloth occurrence in Costa Rica, and assess the effect of climatic factors on spatial patterns using the R-INLA package. Species occurrence data are retrieved using spocc, and spatial climatic variables are obtained with raster. Spatial data and results are manipulated and visualized by means of several packages such as raster and tmap. This paper provides an accessible illustration of spatial point process modeling that can …

Testing The Equality Of Normal Distributed And Independent Groups’ Means Under Unequal Variances By Doex Package, Mustafa Cavus, Berna Yazıcı

The R Journal

In this paper, we present the doex package contains the tests for equality of normal distributed and independent group means under unequal variances such as Cochran F, Welch-Aspin, Welch, Box, Scott-Smith, Brown-Forsythe, Johansen F, Approximate F, Alexander-Govern, Generalized F, Modified Brown-Forsythe, Permutation F, Adjusted Welch, B2, Parametric Bootstrap, Fiducial Approach, and Alvandi Generalized F-test. Most of these tests are not available in any package. Thus, doex is easy to use for researchers in multidisciplinary studies. In this study, an extensive Monte-Carlo simulation study is conducted to investigate the performance of the the tests for equality of normal distributed group means …

News From The Bioconductor Project, Bioconductor Core Team

The R Journal

Bioconductor provides tools for the analysis and comprehension of high-throughput genomic data. Bioconductor 3.12 was released on 28 October, 2020. It is compatible with R 4.0.3 and consists of 1974 software packages, 398 experiment data packages, 968 up-to-date annotation packages, and 28 workflows. Books are a new addition, built regularly from source and therefore fully reproducible; an example is the community-developed Orchestrating Single-Cell Analysis with Bioconductor.

A Unified Algorithm For The Non-Convex Penalized Estimation: The Ncpen Package, Dongshin Kim, Sangin Lee, Sunghoon Kwon

The R Journal

Various R packages have been developed for the non-convex penalized estimation but they can only be applied to the smoothly clipped absolute deviation (SCAD) or minimax concave penalty (MCP). We develop an R package, entitled ncpen, for the non-convex penalized estimation in order to make data analysts to experience other non-convex penalties. The package ncpen implements a unified algorithm based on the convex concave procedure and modified local quadratic approximation algorithm, which can be applied to a broader range of non-convex penalties, including the SCAD and MCP as special examples. Many user-friendly functionalities such as generalized information criteria, cross-validation …

User-Specified General-To-Specific And Indicator Saturation Methods, Genaro Sucarrat

The R Journal

General-to-Specific (GETS) modelling provides a comprehensive, systematic and cumulative approach to modelling that is ideally suited for conditional forecasting and counterfactual analysis, whereas Indicator Saturation (ISAT) is a powerful and flexible approach to the detection and estimation of structural breaks (e.g. changes in parameters), and to the detection of outliers. To these ends, multi path backwards elimination, single and multiple hypothesis tests on the coefficients, diagnostics tests andgoodness-of-fit measures are combined to produce a parsimonious final model. In many situations a specific model or estimator is needed, a specific set of diagnostics tests may be required, or a specific f …

Editorial, Michael J. Kane

The R Journal

On behalf of the editorial board, I am pleased to present Volume 12 Issue 2 of the R Journal. This is my third and final issue as the Editor-in-Chief. In the last year, we have made some substantial changes to the journal that I believe will continue to increase our capacity to support the growing data science and computational statistics communities, and continue to raise the visibility of the journal. In the last few months we recruited 10 Associate Editors and we are continuing the recruitment process. I’d like to publicly welcome our new Associate Editors, and thank each of …

E-Rum2020: How We Turned A Physical Conference Into A Successful Virtual Event, Mariachiara Fortuna, Francesca Vitalini, Mirko Signorelli, Emanuela Furfaro, Federico Marini, Gert Janssenswillen, Riccardo Porreca, Riccardo L. Rossi, Andrea Guzzo, Roberta Sirovich, Andrea Melloncelli, Lorenzo Salvi, Serena Signorelli, Filippo Chiarello

The R Journal

The European R Users Meeting 2020 (e-Rum2020) was a conference that was held virtually in June 2020. Originally, e-Rum2020 had been planned as a physical event to be held in Milano. However, the spread of the COVID-19 pandemic and the declaration of a nationwide lockdown induced the Organizing Committee to fully rethink the event, and to turn it into a live virtual conference. In this article, we describe the challenges that we encountered during the organization of e-Rum2020, and how wereacted to them. In doing so, we aim to provide future conference organizers with useful information on how to organize …

Miwqs: Multiple Imputation Using Weighted Quantile Sum Regression, Paul M. Hargarten, David C. Wheeler

The R Journal

The miWQS package in the Comprehensive R Archive Network (CRAN) utilizes weighted quantile sum regression (WQS) in the multiple imputation (MI) framework. The data analyzed is a set/mixture of continuous and correlated components/chemicals that are reasonable to combine in an index and share a common outcome. These components are also interval-censored between zero and upper thresholds, or detection limits, which may differ among the components. This type of data is found in areas such as chemical epidemiological studies, sociology, and genomics. The miWQS package can be run using complete or incomplete data, which may be placed in the first quantile, …

News From The Forwards Taskforce, Heather Turner

The R Journal

Forwards is an R Foundation taskforce working to widen the participation of under represented groups in the R project and in related activities, such as the useR! conference. This report rounds up activities of the taskforce during the second half of 2020.

Farmtest: An R Package For Factor-Adjusted Robust Multiple Testing, Koushiki Bose, Jianqing Fan, Yuan Ke, Xiaoou Pan, Wen-Xin Zhou

The R Journal

We provide a publicly available library FarmTest in the R programming system. This library implements a factor-adjusted robust multiple testing principle proposed by Fan et al. (2019) for large-scale simultaneous inference on mean effects. We use a multi-factor model to explicitly capture the dependence among a large pool of variables. Three types of factors are considered: observable, latent, and a mixture of observable and latent factors. The non-factor case, which corresponds to standard multiple mean testing under weak dependence, is also included. The library implements a series of adaptive Huber methods integrated with fast data-driven tuning schemes to estimate model …

Trace: A Differentiable Approach To Line-Level Stroke Recovery For Offline Handwritten Text, Taylor Neil Archibald

Theses and Dissertations

Stroke order and velocity are helpful features in the fields of signature verification, handwriting recognition, and handwriting synthesis. Recovering these features from offline handwritten text is a challenging and well-studied problem. We propose a new model called TRACE (Trajectory Recovery by an Adaptively-trained Convolutional Encoder). TRACE is a differentiable approach using a convolutional recurrent neural network (CRNN) to infer temporal stroke information from long lines of offline handwritten text with many characters. TRACE is perhaps the first system to be trained end-to-end on entire lines of text of arbitrary width and does not require the use of dynamic exemplars. Moreover, …

Projected Impact Of Mid-21st Century Climate Change On Wildfire Hazard In A Major Urban Watershed Outside Portland, Oregon Usa, Andy Mcevoy, Max Nielsen-Pincus, Andres Holz, Arielle J. Catalano, Kelly E. Gleason

Environmental Science and Management Faculty Publications and Presentations

Characterizing wildfire regimes where wildfires are uncommon is challenged by a lack of empirical information. Moreover, climate change is projected to lead to increasingly frequent wildfires and additional annual area burned in forests historically characterized by long fire return intervals. Western Oregon and Washington, USA (westside) have experienced few large wildfires (fires greater than 100 hectares) the past century and are characterized to infrequent large fires with return intervals greater than 500 years. We evaluated impacts of climate change on wildfire hazard in a major urban watershed outside Portland, OR, USA. We simulated wildfire occurrence and fire regime characteristics under …

Stable Isotope Composition Of Surface Water Across Central Mexico, Jordan Foote

Earth & Environmental Sciences Theses - Archive

Understanding the controlling factors of modern surface water stable isotope compositions is important for reconstructions of paleoclimate and paleoelevation. Few studies have attempted to understand patterns of surface water isotope compositions and their controlling factors in Mexico. Here I study the δ18O, δD and d-excess values of 124 modern river, lake and spring water samples across the Sierra Madre Occidental, Central Mexican Plateau and Sierra Madre Oriental to constrain the spatial pattern and lapse rate. These samples were collected at various elevations after the wet season in 2019. The isotope data were integrated with moisture back trajectory analysis and climatic …

Investigation Of Clinoptilolite Zeolite As A Candidate System For Study By Positron Annihilation, Edward Perez

Physics Theses - Archive

This thesis reports on the characterization of a clinoptilolite zeolite (〖Na〗_3 [〖Al〗_3 〖Si〗_15 O_36 ]12H_2 O) using Energy-dispersive X-ray spectroscopy (EDX/EDS) for chemical analysis, low energy Secondary Electron (SE) analysis for three-dimensional imaging and topography, and Transmission Electron Microscopy (TEM) for two-dimensional imaging at the nanometer level. The goal of this work was to provide additional information that can aid in the interpretation of the data obtained using positron beam based spectroscopies. The measurements were performed using the Hitachi S-3000N Variable Pressure Scanning Electron Microscope (SEM) integrated with a NORAN 7 EDS/EBSD system, the Hitachi S-4800 II Field Emission Scanning …

Generalized Algorithmic Frameworks For Optimizing Distance Calls In Generalized Metric Space Proximity Problems And Methods For Realizing Efficient Signal Reconstruction, Jees Augustine

Computer Science and Engineering Dissertations - Archive

The exponential rise in data, along with its heterogeneity and complexity, helped individuals, businesses, hospitals, enterprises and even governments to thrive on data-driven decision making. However, as the size and complexity of the data surged, challenges in searching for similar objects within databases (proximity search) compounded. As is well known, proximity search is the key and successful method used in Information Retrieval (IR) in vast databases including, Genomics Databases, Image Databases, Video Databases, Text databases, etc. The objective is to retrieve contents from the database, similar to a given object in the database. This dissertation revisits a suite of popular …

Analiza E Efekteve Shëndetsore Gjatë Përdorimit Të Rrjetave Pa Tela Në Kushtet E Jetës Reale, Hashim Sahiti

Theses and Dissertations

Teknologjia Wireless u ideua në 1880 nga Alexander Graham Bell dhe Sumner Tainted kur u zbulua telefoni fotografik. Në ditët e sotme, ka shumë lloje të pajisjeve pa tela që përdoren për të komunikuar. Telefoni celular dhe Rrjeti Wireless janë pjesa e jetës sonë të përditshme në të gjithë botën. Pajisja Wi-Fi lejon shkëmbimin (marrjen dhe dërgimin) e të dhënave përmes pajisjeve pa tela dhe Wi-Fi lëshojnë valë radio. Pajisjet që përdorin Wi-Fi janë kompjuterët, tabletat, celularët, audio player, aparatet fotografikë digjital si dhe pajisjet përcjellëse te kompjuterit si printerët, tastiera, miu e etj. Pajisjet pa tela janë të bazuara …

Vitrina Virtuale E Librit, Genti Sheholli

Theses and Dissertations

Zhvillimi i aplikacioneve moderne në ditët e sotme nuk është vetëm proces i ndërtimit të aplikacionit. Procesi përfshin zhvillimin e shërbimeve në anën e serverit dhe aplikacionit në anën e klientit. Teknologjitë dhe opsionet për të zhvilluar një web aplikacion janë të shumta dhe varësisht se cfarë web aplikacioni duhet të zhvillohet mund të vendosim edhe për teknologjitë në secilin aspekt.

Qëllimi i këtij web aplikacioni është hulmtimi në teknologjit të kohës që kanë marrë hov të zhvillimit në aplikacionet moderne dhe hulumtim në zhvillimin e aplikacionit me struktura moderne.

Ky web aplikacion është një sintezë e proceseve, procedurave dhe …

Analizimi Dhe Zhvillimi I Sistemit Për Komunikim Në Telemjekësi Duke Përdorur Teknologjinë Webrtc, Fitim Mehmeti

Theses and Dissertations

Sistemet softuerike për komunikim në përgjithësi e në veçanti telemedicina që për qëllim ka ofrimin e kujdesit shëndetsor në distancë janë duke u bërë aset i rëndësishëm në shtetet e zhvilluara. Kufizimet në kohë, vendndodhja, kushtet atmosferike, tash së fundmi edhe pandemia COVID-19 janë ndër arsyet kryesore për zhvillimin e sistemeve të tilla. Ky punim është përqëndruar në hulumtimin, analizimin dhe krahasimin e sistemeve për komunikim online, mënyra se si funksionojnë këto sisteme, gjithashtu është fokusuar në zhvillimin e një aplikacioni për komunikim me video për pacientët dhe mjekët duke përdorur teknologjinë webRTC, ky projekt do të zhvillohet në bazë …

Ndikimi I Ueb Aplikacionit Dhe Aplikacionit Për Telefonë Në Menaxhimin Dhe Shperndarjen E Informacionit Në Ditët E Sotme, Jetmir Feka

Theses and Dissertations

Në kohën tonë teknologjia po ecën me hapa shumë të shpejtë, sidomos në fushën e pajisjeve elektronike si: kompjuterët, tabletat, telefonat e mençur etj. Numri i përdoruesve të internetit dhe pajisjeve elektronike është shumë i madh dhe është në rritje të vazhdueshme. Qëllimi i këtij hulumtimi është identifikimi efektiv i strategjisë për zhvillimin e sistemit të menaxhimeve të portaleve online, si dhe efikasitetin në shpërndarjen e tyre. Një kompanie i nevojitet një sistem për menaxhim të lajmeve i cili është një element kryesor në zhvillimin e kompanisë. Shumica e kompanive mediatike sot kanë krijuar ueb-sajte online në mënyrë që punën …

Ndërtimi I Një "To-Do" Aplikacioni Me Teknologjinë Flutter, Emnolina Brahimi

Theses and Dissertations

Aplikacionet për telefon mobil viteve të fundit kanë filluar të zëvendësojnë shumë veprimtari që në të shkuarën i kemi bërë në mënyrë primitive te themi. Nevoja për të kursyer sa më shumë kohë, energji dhe para ka bërë që të krijohen aplikacione të ndryshme, inovative dhe mbi të gjitha aplikacione që ofrojnë zgjidhje të problemeve.

Smartphone-ët por edhe shumë pajisje të tjera elektronike si tabletet dhe smartwatch janë bërë aq të nevojshme sa që pothuajse secili person i rritur mund të posedoj një të tillë.

Duke parë kërkesën dhe nevojën në tregun tonë për zgjidhje të problemeve përmes aplikacioneve, si …