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Full-Text Articles in Computer Sciences

Changes On Cran, Kurt Hornik, Uwe Ligges, Achim Zeileis Dec 2020

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 Dec 2020

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 Dec 2020

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 Dec 2020

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 …


Tulip: A Toolbox For Linear Discriminant Analysis With Penalties, Yuqing Pan, Qing Mai, Xin Zhang Dec 2020

Tulip: A Toolbox For Linear Discriminant Analysis With Penalties, Yuqing Pan, Qing Mai, Xin Zhang

The R Journal

Linear discriminant analysis (LDA) is a powerful tool in building classifiers with easy computation and interpretation. Recent advancements in science technology have led to the popularity of datasets with high dimensions, high orders and complicated structure. Such datasetes motivate the generalization of LDA in various research directions. The R package TULIP integrates several popular high-dimensional LDA-based methods and provides a comprehensive and user-friendly toolbox for linear, semi-parametric and tensor-variate classification. Functions are included for model fitting, cross validation and prediction. In addition, motivated by datasets with diverse sources of predictors, we further include functions for covariate adjustment. Our package is …


Testing The Equality Of Normal Distributed And Independent Groups’ Means Under Unequal Variances By Doex Package, Mustafa Cavus, Berna Yazıcı Dec 2020

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 Dec 2020

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.


Kuhn-Tucker And Multiple Discrete-Continuous Extreme Value Model Estimation And Simulation In R: The Rmdcev Package, Patrick Lloyd-Smith Dec 2020

Kuhn-Tucker And Multiple Discrete-Continuous Extreme Value Model Estimation And Simulation In R: The Rmdcev Package, Patrick Lloyd-Smith

The R Journal

This paper introduces the package rmdcev in R for estimation and simulation of KuhnTucker demand models with individual heterogeneity. The models supported by rmdcev are the multiple-discrete continuous extreme value (MDCEV) model and Kuhn-Tucker specification common in the environmental economics literature on recreation demand. Latent class and random parameters specifications can be implemented and the models are fit using maximum likelihood estimation or Bayesian estimation. The rmdcev package also implements demand forecasting and welfare calculation for policy simulation. The purpose of this paper is to describe the model estimation and simulation framework and to demonstrate the functionalities of rmdcev using …


A Unified Algorithm For The Non-Convex Penalized Estimation: The Ncpen Package, Dongshin Kim, Sangin Lee, Sunghoon Kwon Dec 2020

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 Dec 2020

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 Dec 2020

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 …


Openland: Software For Quantitative Analysis And Visualization Of Land Use And Cover Change, Reginal Exavier, Peter Zeilhofer Dec 2020

Openland: Software For Quantitative Analysis And Visualization Of Land Use And Cover Change, Reginal Exavier, Peter Zeilhofer

The R Journal

There is an increasing availability of spatially explicit, freely available land use and cover (LUC) time series worldwide. Because of the enormous amount of data this represents, the continuous updates and improvements in spatial and temporal resolution and category differentiation, as well as increasingly dynamic and complex changes made, manual data extraction and analysis is highly time consuming, and making software tools available to automatize LUC data assessment is becoming imperative. This paper presents a software developed in R, which combines LUC raster time series data and their transitions, calculates state-of-the-art LUC change indicators, and creates spatio-temporal visualizations, all in …


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 Dec 2020

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 Dec 2020

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 Dec 2020

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 Dec 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 …


Packet Delivery: An Investigation Of Educational Video Games For Computer Science Education, Robert Lafferty Dec 2020

Packet Delivery: An Investigation Of Educational Video Games For Computer Science Education, Robert Lafferty

School of Computing: Dissertations, Theses, and Student Research

The field of educational video games has rapidly grown since the 1970s, mostly producing video games to teach core education concepts such as mathematics, natural science, and English. Recently, various research groups have developed educational games to address elective topics such as finance and health. Educational video games often target grade school audiences and rarely target high school students, college students, or adults. Computer science topics are not a common theme among educational video games; the games that address Computer Science topics teach computer fundamentals, such as typing or basic programming, to young audiences.

Packet Delivery, an educational video …


Machine Learning Augmentation Micro-Sensors For Smart Device Applications, Mohammad H. Hasan Nov 2020

Machine Learning Augmentation Micro-Sensors For Smart Device Applications, Mohammad H. Hasan

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Novel smart technologies such as wearable devices and unconventional robotics have been enabled by advancements in semiconductor technologies, which have miniaturized the sizes of transistors and sensors. These technologies promise great improvements to public health. However, current computational paradigms are ill-suited for use in novel smart technologies as they fail to meet their strict power and size requirements. In this dissertation, we present two bio-inspired colocalized sensing-and-computing schemes performed at the sensor level: continuous-time recurrent neural networks (CTRNNs) and reservoir computers (RCs). These schemes arise from the nonlinear dynamics of micro-electro-mechanical systems (MEMS), which facilitates computing, and the inherent ability …


Formal Concept Analysis Applications In Bioinformatics, Sarah Roscoe Nov 2020

Formal Concept Analysis Applications In Bioinformatics, Sarah Roscoe

School of Computing: Dissertations, Theses, and Student Research

Bioinformatics is an important field that seeks to solve biological problems with the help of computation. One specific field in bioinformatics is that of genomics, the study of genes and their functions. Genomics can provide valuable analysis as to the interaction between how genes interact with their environment. One such way to measure the interaction is through gene expression data, which determines whether (and how much) a certain gene activates in a situation. Analyzing this data can be critical for predicting diseases or other biological reactions. One method used for analysis is Formal Concept Analysis (FCA), a computing technique based …


Investigating Factors Predicting Effective Learning In A Cs Professional Development Program For K–12 Teachers, Patrick Morrow Oct 2020

Investigating Factors Predicting Effective Learning In A Cs Professional Development Program For K–12 Teachers, Patrick Morrow

School of Computing: Dissertations, Theses, and Student Research

The demand for K-12 Computer Science (CS) education is growing and there is not an adequate number of educators to match the demand. Comprehensive research was carried out to investigate and understand the influence of a summer two-week professional development (PD) program on teachers’ CS content and pedagogical knowledge, their confidence in such knowledge, their interest in and perceived value of CS, and the factors influencing such impacts. Two courses designed to train K-12 teachers to teach CS, focusing on both concepts and pedagogy skills were taught over two separate summers to two separate cohorts of teachers. Statistical and SWOT …


Research 4.0: Research In The Age Of Automation, Rob Procter, Ben Glover, Elliot Jones Sep 2020

Research 4.0: Research In The Age Of Automation, Rob Procter, Ben Glover, Elliot Jones

Copyright, Fair Use, Scholarly Communication, etc.

Executive Summary

There is a growing consensus that we are at the start of a fourth industrial revolution, driven by developments in Artificial Intelligence, machine learning, robotics, the Internet of Things, 3-D printing, nanotechnology, biotechnology, 5G, new forms of energy storage and quantum computing. This wave of technical innovations is already having a significant impact on how research is conducted, with dramatic change across research methods in recent years within some disciplines, as this project’s interim report set out.

Whilst there are a wide range of technologies associated with the fourth industrial revolution, this report primarily seeks to understand what …


Routing Optimization In Heterogeneous Wireless Networks For Space And Mission-Driven Internet Of Things (Iot) Environments, Sara El Alaoui Aug 2020

Routing Optimization In Heterogeneous Wireless Networks For Space And Mission-Driven Internet Of Things (Iot) Environments, Sara El Alaoui

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

As technological advances have made it possible to build cheap devices with more processing power and storage, and that are capable of continuously generating large amounts of data, the network has to undergo significant changes as well. The rising number of vendors and variety in platforms and wireless communication technologies have introduced heterogeneity to networks compromising the efficiency of existing routing algorithms. Furthermore, most of the existing solutions assume and require connection to the backbone network and involve changes to the infrastructures, which are not always possible -- a 2018 report by the Federal Communications Commission shows that over 31% …


Application Of Software Engineering Principles To Synthetic Biology And Emerging Regulatory Concerns, Justin Firestone Aug 2020

Application Of Software Engineering Principles To Synthetic Biology And Emerging Regulatory Concerns, Justin Firestone

School of Computing: Dissertations, Theses, and Student Research

As the science of synthetic biology matures, engineers have begun to deliver real-world applications which are the beginning of what could radically transform our lives. Recent progress indicates synthetic biology will produce transformative breakthroughs. Examples include: 1) synthesizing chemicals for medicines which are expensive and difficult to produce; 2) producing protein alternatives; 3) altering genomes to combat deadly diseases; 4) killing antibiotic-resistant pathogens; and 5) speeding up vaccine production.

Although synthetic biology promises great benefits, many stakeholders have expressed concerns over safety and security risks from creating biological behavior never seen before in nature. As with any emerging technology, there …


Formal Language Constraints In Deep Reinforcement Learning For Self-Driving Vehicles, Tyler Bienhoff Jul 2020

Formal Language Constraints In Deep Reinforcement Learning For Self-Driving Vehicles, Tyler Bienhoff

School of Computing: Dissertations, Theses, and Student Research

In recent years, self-driving vehicles have become a holy grail technology that, once fully developed, could radically change the daily behaviors of people and enhance safety. The complexities of controlling a car in a constantly changing environment are too immense to directly program how the vehicle should behave in each specific scenario. Thus, a common technique when developing autonomous vehicles is to use reinforcement learning, where vehicles can be trained in simulated and real-world environments to make proper decisions in a wide variety of scenarios. Reinforcement learning models, however, have uncertainties in how the vehicle acts, especially in a previously …


Power-Over-Tether Uas Leveraged For Nearly-Indefinite Meteorological Data Acquisition, Daniel Rico, Carrick Detweiler, Francisco Muñoz-Arriola Jul 2020

Power-Over-Tether Uas Leveraged For Nearly-Indefinite Meteorological Data Acquisition, Daniel Rico, Carrick Detweiler, Francisco Muñoz-Arriola

School of Computing: Dissertations, Theses, and Student Research

Use of unmanned aerial systems (UASs) in agriculture has risen in the past decade. These systems are key to modernizing agriculture. UASs collect and elucidate data previously difficult to obtain and used to help increase agricultural efficiency and production. Typical commercial off-the-shelf (COTS) UASs are limited by small payloads and short flight times. Such limits inhibit their ability to provide abundant data at multiple spatiotemporal scales. In this paper, we describe the design and construction of the tethered aircraft unmanned system (TAUS), which is a novel power-over-tether UAS leveraging the physical presence of the tether to launch multiple sensors along …


Introduction To The R-Package: Usdampr, Elliott James Dennis, Bowen Chen Jun 2020

Introduction To The R-Package: Usdampr, Elliott James Dennis, Bowen Chen

Extension Farm and Ranch Management News

Why the Need for the Package? In the 1990’s, concern over growing packer concentration and a hog industry market shock resulted in discontent among producers and packers. As a result, the United States Congress passed the Livestock Mandatory Reporting Act of 1999 (1999 Act) [Pub. L. 106-78, Title IX] which is required to be reauthorized every five years. See here for a full history of the Livestock Mandatory Reporting Background.

Market reports were publicly issued in the form of .txt files with varying frequency from April 2000 to April 2020. Current and historical data were also housed in a USDA-AMS …


Ari: The Automated R Instructor, Sean Kross, Jeffrey T. Leek, John Muschelli Jun 2020

Ari: The Automated R Instructor, Sean Kross, Jeffrey T. Leek, John Muschelli

The R Journal

We present the ari package for automatically generating technology-focused educational videos. The goal of the package is to create reproducible videos, with the ability to change and update video content seamlessly. We present several examples of generating videos including using R Markdown slide decks, PowerPoint slides, or simple images as source material. We also discuss how ari can help instructors reach new audiences through programmatically translating materials into other languages.


The R Journal (June 2020) 12(1): Complete Issue, The R Foundation Jun 2020

The R Journal (June 2020) 12(1): Complete Issue, The R Foundation

The R Journal

Editorial, Michael J. Kane

Contributed Research Articles

gk: An R Package for the g-and-k and Generalised g-and-h Distributions, Dennis Prangle

NlinTS: An R Package for Causality Detection in Time Series, Youssef Hmamouche

Mapping Smoothed Spatial Effect Estimates from Individual-Level Data: MapGAM, Lu Bai, Daniel L. Gillen, Scott M. Bartell, and Verónica M. Vieira

mudfold: An R Package for Nonparametric IRT Modelling of Unfolding Processes, Spyros E. Balafas, Wim P. Krijnen, Wendy J. Post, and Ernst C. Wit

tsmp: An R Package for Time Series with Matrix Profile, Francisco Bischoff and Pedro Pereira Rodrigues

Individual-Level Modelling of Infectious Disease Data: EpiILM, …


Provenance Of R’S Gradient Optimizers, John C. Nash Jun 2020

Provenance Of R’S Gradient Optimizers, John C. Nash

The R Journal

Gradient optimization methods (function minimizers) are well-represented in both the base and package universe of R (R Core Team, 2019). However, some of the methods and the codes developed from them were published before standards for hardware and software were established, in particular the IEEE arithmetic (IEEE, 1985). There have been cases of unexpected behaviour or outright errors, and these are the focus of the histoRicalg project. A summary history of some of the tools in R for gradient optimization methods is presented to give perspective on such methods and the occasions where they could be used effectively.


S, R, And Data Science, John M. Chambers Jun 2020

S, R, And Data Science, John M. Chambers

The R Journal

Data science is increasingly important and challenging. It requires computational tools and programming environments that handle big data and difficult computations, while supporting creative, high-quality analysis. The R language and related software play a major role in computing for data science. R is featured in most programs for training in the field. R packages provide tools for a wide range of purposes and users. The description of a new technique, particularly from research in statistics, is frequently accompanied by an R package, greatly increasing the usefulness of the description.

The history of R makes clear its connection to data science. …