Computer Sciences Commons^™

Dow Theory's Peak-And-Trough Analysis Justified, Chrysostomos Stylios, Vladik Kreinovich

Departmental Technical Reports (CS)

In the analysis of dynamic financial quantities such as stock prices, equity prices, etc., reasonable results are often obtained if we only consider local maxima ("peaks") and local minima ("troughs") and ignore all the other values. The empirical success of this strategy remains a mystery. In this paper, we provide a possible explanation for this success.

How To Gauge Disruptions Caused By Garbage Collection: Towards An Efficient Algorithm, Gabriel Arellano, Edward Hudgins, David Pruitt, Adrian Veliz, Eric Freudenthal, Vladik Kreinovich

Departmental Technical Reports (CS)

Comprehensive garbage collection is employed on a variety of computing devices, including intelligent cell phones. Garbage collection can cause prolonged user-interface pauses. In order to evaluate and compare the disruptiveness of various garbage collection strategies, it is necessary to gauge disruptions caused by garbage collection. In this paper, we describe efficient algorithms for computing metrics useful for this purpose.

Scope And Challenges In Light Fidelity(Lifi) Technology In Wireless Data Communication, Shubham Chatterjee, Shalabh Agarwal, Asoke Nath

Computer Science Faculty Research & Creative Works

Light Emitting Diodes (LED) are used in different areas of everyday life. The advantage of this device is that in addition to their lightening capabilities, it can be used for data transmissions as well. In the present study, the authors have made an exhaustive study on technology of Li-Fi and its applications in transferring data from one computer to another computer. The authors have also made study on advantages as well as disadvantages of using Li- Fi in transferring data from one computer to another computer. The massive use of Li-Fi may solve some bottleneck of data transmission in Wi-Fi …

Repcoin: A Market-Based Approach To Reputation, Stephen D. Malina

Dartmouth College Undergraduate Theses

Individuals use measures of reputation as heuristics for determining how much interest and trust they should place in other individuals. Clear measures of reputation save time and increase efficiency because they prevent individuals from having to go through the traditional process of determining reputation, especially in cases where these traditional measures no longer suffice. Repcoin aimed to give experts in different areas a platform for highlighting their expertise, provide an avenue for users to find credible experts in different areas, and a place for users to try and predict whose reputation will increase and thereby prove their ability to identify …

Wiprint: 3d Printing Your Wireless Coverage, Justin Chan

Dartmouth College Undergraduate Theses

Wireless signals are everywhere in residential, commercial and industrial environments. Directing wireless signals to conform to custom physical boundaries is of great importance in improving the performance, security and privacy of a wireless system. Unfortunately current solutions like directional antennas are bulky and expensive for ordinary users. We propose WiPrint, a novel approach to customizing wireless signal maps using 3D printed glossy reflectors. This solution is easily manufactured and adapts easily to different environments. The WiPrint system is highly flexible as it does not require adding additional APs or moving the AP to new locations. This is significant in the …

Repcoin: The Only Reputation Market, Matthew Ritter

Dartmouth College Undergraduate Theses

With the internet taking over as a one-stop shop for information, finding credible material is becoming difficult. People look increasingly to the web to satisfy their questions along with their professional and entertainment needs. For the content seeker, the right content can be hard to find. Forums are cluttered with unreliable answers, entertainment sites overflow with mediocre artists, and professional searches yield countless novices. For the content creator, building a credible online presence is also difficult. Bloggers and professionals can be drowned out by similar candidates. Repcoin attempts to alleviate problems for both the content creator and the content seeker …

Optimal Defensive Strategies In One-Dimensional Risk, Darren B. Glass, Todd W. Neller

Math Faculty Publications

We consider a one-dimensional version of the board game RISK and discuss the problem of how a defending player might choose to distribute his armies along a chain of territories in order to maximize the probability of survival. In particular, we analyze a Markov chain model of this situation and run computer simulations in order to make conjectures as to the optimal strategies. The latter sections of the paper analyze this strategy rigorously and use results on recurrence relations and probability theory in order to prove a related result.

How To Take Into Account A Student's Degree Of Certainty When Evaluating The Test Results, Joe Lorkowski, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

To more adequately gauge the student's knowledge, it is desirable to take into account not only whether the student's answers on the test are correct or nor, but also how confident the students are in their answers. For example, a situation when a student gives a wrong answer, but understands his/her lack of knowledge on this topic, is not as harmful as the situation when the student is absolutely confident in his/her wrong answer. In this paper, we use the general decision making theory to describe the best way to take into account the student's degree of certainty when evaluating …

In Engineering Classes, How To Assign Partial Credit: From Current Subjective Practice To Exact Formulas (Based On Computational Intelligence Ideas), Joe Lorkowski, Vladik Kreinovich, Olga Kosheleva

Departmental Technical Reports (CS)

When a student performed only some of the steps needed to solve a problem, this student gets partial credit. This partial credit is usually proportional to the number of stages that the student performed. This may sound reasonable, but in engineering education, this leads to undesired consequences: for example, a student who did not solve any of the 10 problems on the test, but who successfully performed 9 out of 10 stages needed to solve each problem will still get the grade of A ("excellent"). This may be a good evaluation of the student's intellectual ability, but for a engineering …

"Time For Dabs": Analyzing Twitter Data On Butane Hash Oil Use, Raminta Daniulaityte, Robert G. Carlson, Farahnaz Golroo, Sanjaya Wijeratne, Edward W. Boyer, Silvia S. Martins, Ramzi W. Nahhas, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

Why Fuzzy Cognitive Maps Are Efficient, Vladik Kreinovich, Chrysostomos Stylios

Departmental Technical Reports (CS)

In many practical situations, the relation between the experts' degrees of confidence in different related statements is well described by Fuzzy Cognitive Maps (FCM). This empirical success is somewhat puzzling, since from the mathematical viewpoint, each FCM relation corresponds to a simplified one-neuron neural network, and it is well known that to adequately describe relations, we need multiple neurons. In this paper, we show that the empirical success of FCM can be explained if we take into account that human's subjective opinions follow Miller's seven plus minus two law.

Dynamic Voxel Based Terrain Generation, Thomas Sanford

Computer Science and Software Engineering

This project is an implementation of an editable terrain system. By maintaining an octree of volumetric data and performing the mesh creation on the GPU, the program can allow for free editing of the surroundings which is then reflected in real time. This allows for real time applications to have terrain that can change depending on how the user interacts with it.

Multiplayer Browser-Based Game Utilizing Javascript And Webgl Frameworks, Cy Tan, Benjamin Naftali, Matthew Tong, Vincent Chan

Computer Science and Software Engineering

The goal of our project is to make an online large-scale multiplayer game with persistent user data. This will involve real-time player interaction and many customization options. This game will be a massively-multiplayer online tactics role-playing game (MMOTRPG), a genre that has been insufficiently explored. This area of browser-based massive multiplayer games is also a platform of gaming that has yet to realize the capabilities of modern browsers and the level of interaction and graphics they now support.

The scope of our project does not encompass the complete feature set we have intended for the game, but rather a technical …

Resound.Fm, Matthew Bleifer

Computer Science and Software Engineering

The goal of this senior project was to create a social platform for people to share and discover the music they love. Current music streaming technologies lack an effective tool for helping users find new music. The personal element of music that used to exist in the days that people gathered around record players or shared mixtapes has been lost online and Resound.fm seeks to bring it back. Resound.fm is a Ruby on Rails web application, which uses some of the latest web technologies and design patterns to create a powerful new music discovery experience online. The project was completed …

Changes In R, R Core Team

The R Journal

CHANGES IN R 3.2.1

CHANGES IN R 3.2.0

CHANGES IN R 3.1.3

Changes On Cran, Kurt Hornik, Achim Zeileis

The R Journal

New packages in CRAN task views

New contributed packages

Other changes

R Foundation News, Kurt Hornik

The R Journal

Donations

New Supporting Institutions

New Supporting Members

Identifying Complex Causal Dependencies In Configurational Data With Coincidence Analysis, Michael Baumgartner, Alrik Thiem

The R Journal

We present cna, a package for performing Coincidence Analysis (CNA). CNA is a configurational comparative method for the identification of complex causal dependencies—in particular, causal chains and common cause structures—in configurational data. After a brief introduction to the method’s theoretical background and main algorithmic ideas, we demonstrate the use of the package by means of an artificial and a real-life data set. Moreover, we outline planned enhancements of the package that will further increase its applicability.

Fslr: Connecting The Fsl Software With R, John Muschelli, Elizabeth Sweeney, Martin Lindquist, Ciprian Crainiceanu

The R Journal

We present the package fslr, a set of R functions that interface with FSL (FMRIB Software Library), a commonly-used open-source software package for processing and analyzing neuroimaging data. The fslr package performs operations on ‘nifti’ image objects in R using command-line functions from FSL, and returns R objects back to the user. fslr allows users to develop image processing and analysis pipelines based on FSL functionality while interfacing with the functionality provided by R. We present an example of the analysis of structural magnetic resonance images, which demonstrates how R users can leverage the functionality of FSL without switching …

The R Journal (June 2015) 7(1): Complete Issue, The R Foundation

The R Journal

Editorial, Bettina Grün

Contributed Research Articles

Peptides: A Package for Data Mining of Antimicrobial Peptides, Daniel Osorio, Paola Rondón-Villarreal, and Rodrigo Torres

fanplot: An R Package for Visualising Sequential Distributions, Guy J. Abel

sparkTable: Generating Graphical Tables for Websites and Documents with R, Alexander Kowarik, Bernhard Meindl, and Matthias Templ

rdrobust: An R Package for Robust Nonparametric Inference in Regression-Discontinuity Designs, Sebastian Calonico, Matias D. Cattaneo, and Rocío Titiunik

Frames2: A Package for Estimation in Dual Frame Surveys, Antonio Arcos, David Molina, Maria Giovanna Ranalli, and María del Mar Rueda

The Complex Multivariate Gaussian Distribution, Robin K. S. Hankin

sae: …

R As An Environment For Reproducible Analysis Of Dna Amplification Experiments, Stefan Rödiger, Michał Burdukiewicz, Konstantin Blagodatskikh, Michael Jahn, Peter Schierack

The R Journal

There is an ever-increasing number of applications, which use quantitative PCR (qPCR) or digital PCR (dPCR) to elicit fundamentals of biological processes. Moreover, quantitative isothermal amplification (qIA) methods have become more prominent in life sciences and point-of-care diagnostics. Additionally, the analysis of melting data is essential during many experiments. Several software packages have been developed for the analysis of such datasets. In most cases, the software is either distributed as closed source software or as monolithic block with little freedom to perform highly customized analysis procedures. We argue, among others, that R is an excellent foundation for reproducible and transparent …

Sae: An R Package For Small Area Estimation, Isabel Molina, Yolanda Marhuenda

The R Journal

We describe the R package sae for small area estimation. This package can be used to obtain model-based estimates for small areas based on a variety of models at the area and unit levels, along with basic direct and indirect estimates. Mean squared errors are estimated by analytical approximations in simple models and applying bootstrap procedures in more complex models. We describe the package functions and show how to use them through examples.

Frames2: A Package For Estimation In Dual Frame Surveys, Antonio Arcos, David Molina, Maria Giovanna Ranalli, Maria Del Mar Rueda

The R Journal

Data from complex survey designs require special consideration with regard to estimation of finite population parameters and corresponding variance estimation procedures, as a consequence of significant departures from the simple random sampling assumption. In the past decade a number of statistical software packages have been developed to facilitate the analysis of complex survey data. All these statistical software packages are able to treat samples selected from one sampling frame containing all population units. Dual frame surveys are very useful when it is not possible to guarantee a complete coverage of the target population and may result in considerable cost savings …

Sparktable: Generating Graphical Tables For Websites And Documents With R, Alexander Kowarik, Bernhard Meindl, Matthias Templ

The R Journal

Visual analysis of data is important to understand the main characteristics, main trends and relationships in data sets and it can be used to assess the data quality. Using the R package sparkTable, statistical tables holding quantitative information can be enhanced by including spark-type graphs such as sparklines [] and sparkbars [].

These kind of graphics are well-known in literature and are considered as simple, intense and illustrative graphs that are small enough to fit in a single line. Thus, they can easily enrich tables and texts with additional information in a comprehensive visual way.

The R package sparkTable …

Fanplot: An R Package For Visualising Sequential Distributions, Guy J. Abel

The R Journal

Fan charts, first developed by the Bank of England in 1996, have become a standard method for visualising forecasts with uncertainty. Using shading fan charts focus the attention towards the whole distribution away from a single central measure. This article describes the basics of plotting fan charts using an R add-on package alongside some additional methods for displaying sequential distributions. Examples are based on distributions of both estimated parameters from a time series model and future values with uncertainty.

The Gridgraphics Package, Paul Murrell

The R Journal

The gridGraphics package provides a function, grid.echo(), that can be used to convert a plot drawn with the graphics package to a visually identical plot drawn using grid. This conversion provides access to a variety of grid tools for making customisations and additions to the plot that are not possible with the graphics package/

Peptides: A Package For Data Mining Of Antimicrobial Peptides, Daniel Osorio, Paola Rondón-Villarreal, Rodrigo Torres

The R Journal

Antimicrobial peptides (AMP) are a promising source of antibiotics with a broad spectrum activity against bacteria and low incidence of developing resistance. The mechanism by which an AMPexecutes its function depends on a set of computable physicochemical properties from the amino acid sequence. The Peptides package was designed to allow the quick and easy computation of ten structural characteristics own of the antimicrobial peptides, with the aim of generating data to increase the accuracy in classification and design of new amino acid sequences. Moreover, the options to read and plot XVG output files from GROMACS molecular dynamics package are included.

Correspondence Analysis On Generalised Aggregated Lexical Tables (Ca-Galt) In The Factominer Package, Belchin Kostov, Mónica Bécue-Bertaut, François Husson

The R Journal

Correspondence analysis on generalised aggregated lexical tables (CA-GALT) is a method that generalizes classical CA-ALT to the case of several quantitative, categorical and mixed variables. It aims to establish a typology of the external variables and a typology of the events from their mutual relationships. In order to do so, the influence of external variables on the lexical choices is untangled cancelling the associations among them, and to avoid the instability issued from multicollinearity, they are substituted by their principal components. The CaGalt function, implemented in the FactoMineR package, provides numerous numerical and graphical outputs. Confidence ellipses are also provided …

Rdrobust: An R Package For Robust Nonparametric Inference In Regression-Discontinuity Designs, Sebastian Calonico, Matias D. Cattaneo, Rocío Titiunik

The R Journal

This article describes the R package rdrobust, which provides data-driven graphical and in ference procedures for RD designs. The package includes three main functions: rdrobust, rdbwselect and rdplot. The first function (rdrobust) implements conventional local-polynomial RD treatment effect point estimators and confidence intervals, as well as robust bias-corrected confidence intervals, for average treatment effects at the cutoff. This function covers sharp RD, sharp kink RD, fuzzy RD and fuzzy kink RD designs, among other possibilities. The second function (rdbwselect) implements several bandwidth selectors proposed in the RD literature. The third function (rdplot) provides data-driven optimal choices of evenly-spaced and …

News From The Bioconductor Project, Bioconductor Team

The R Journal

The Bioconductor project provides tools for the analysis and comprehension of high throughput genomic data. The 1024 software packages available in Bioconductor can be viewed at http://bioconductor.org/packages/. Navigate packages using ‘biocViews’ terms and title search. Each package has an html page with a description, links to vignettes, reference manuals, and usage statistics. Start using Bioconductor version 3.1 by installing R 3.2.1 and evaluating the commandS