November 2019

Does using dtplyr make sense for all datasets?

November 27, 2019 | Sebastian Wolf

When Hadley Wickham published dtplyr 1.0.0 last week, I was super excited. Moreover, I wanted to know, if it really is a useful package. Therefore I performed some tiny research being presented in this blog entry. Ok. So dtplyr gives you the speed of data.table with the nice API of ...

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Non-negative least squares

November 27, 2019 | kjytay

Imagine that one has a data matrix consisting of observations, each with features, as well as a response vector . We want to build a model for using the feature columns in . In ordinary least squares (OLS), one seeks … Continue reading →

$\hat{\beta} \in \mathbb{R}^p$

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An example of base::split() for looping through groups

November 26, 2019 | Very statisticious on Very statisticious

I recently had a question from a client about the simplest way to subset a data.frame and apply a function to each subset. “Simplest” could mean many things, of course, since what is simple for one person could appear very difficult to another. In this specific case I suggested ... [Read more...]

lmds: Landmark Multi-Dimensional Scaling

November 26, 2019 | R | Robrecht Cannoodt

Multi-dimensional scaling (MDS) (Kruskal 1964) is a dimensionality reduction method used for visualising and denoising high-dimensional data. However, since MDS requires calculating the distances between all pairs of data points, it does not scale ...

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lmds: Landmark Multi-Dimensional Scaling

November 26, 2019 | R | Robrecht Cannoodt

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How to easily make a ROC curve in R

November 26, 2019 | chris2016

A typical task in evaluating the results of machine learning models is making a ROC curve, this plot can inform the analyst how well a model can discriminate one class from a second. We developed MLeval (https://cran.r-project.org/web/packages/MLeval/index.html), a evaluation package for R, ...

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Learning Data Science: Sentiment Analysis with Naive Bayes

November 26, 2019 | Learning Machines

As we have already seen in former posts simple methods can be surprisingly successful in yielding good results (see e.g Learning Data Science: Predicting Income Brackets or Teach R to read handwritten Digits with just 4 Lines of Code). If you want to learn how some simple mathematics, known as ... [Read more...]

rnassqs: accessing USDA agricultural data via API

November 25, 2019 | rOpenSci - open tools for open science

The United States Deparment of Agriculture National Agricultural Statistics Service (USDA-NASS) provides a wide range of agricultural data that includes animal, crop, demographic, economic, and environmental measures across a number of geographies and time periods. This data is available by direct download or queriable via the Quick Stats interface. While ... [Read more...]

Introducing sortable to add drag-and-drop to your shiny apps

November 25, 2019 | R Views

Andrie de Vries is the author of “R for Dummies” and a Solutions Engineer at RStudio Earlier this year I was a student on the RStudio Instructor Training, taught by the inspiratational Greg Wilson. I remember several tips from this course, for example that you should always try to draw ...

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Search and discover CRAN packages with pkgsearch!

November 25, 2019 | Posts on R-hub blog

We have just released version 3.0.1 of the pkgsearch package on CRAN! ???? pkgsearch munges CRAN metadata and lets you access it through several lenses: search packages by keyword, popularity, recent activity, package name and more. Get pkgsearch’s latest version from a safe CRAN mirror near you: install.packages("pkgsearch") This ...

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Automated testing with ‘testthat’ in practice

November 25, 2019 | R on Coding Club UC3M

by Virginia Peón García You test your code. We know you do. How else are you sure that your changes don’t break the program? But after you commit, you discard those pesky scripts and throw away code. Don’t you think it’s a bit of a ...

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Adding a “mixture” distribution to the simstudy package

November 25, 2019 | Keith Goldfeld

I am contemplating adding a new distribution option to the package simstudy that would allow users to define a new variable as a mixture of previously defined (or already generated) variables. I think the easiest way to explain how to apply the new mixture option is to step through a ...

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Accupedo vs. Fitbit Part 2: Convergent Validity of Cumulative Step Counts with R

November 25, 2019 | Method Matters

This post is a continuation of the previous post on this blog. Last time, we analyzed hourly step count data from the Accupedo app on my phone, and from the Fitbit I wear on my wrist. This time, we will analyze the cumulative step count measurements taken from Accupedo and ...

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ModSpace Collaboration Software for Data Science Teams

November 25, 2019 | Mango Solutions

The ability to collaborate and share resources and information across distributed, and often siloed, data science teams is a common... The post ModSpace Collaboration Software for Data Science Teams appeared first on Mango Solutions. [Read more...]

Health Economics in R Hackathon

November 25, 2019 | Nathan Green

Imperial College 2019 On November 6th – 7th 2019 at Imperial College London, we hosted the first health economics in R hackathon. The event was aimed at health economists, statistcians and R users who are interested in creating new R tools to tackle problems in health economics large or small. There was a ...

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Creating WordPress blog posts with RMarkdown

November 25, 2019 | Nathan Green

R Markdown This blog post is written as an R Markdown document. Markdown is a simple formatting syntax for authoring HTML, PDF, and MS Word documents. For more details on using R Markdown see http://rmarkdown.rstudio.com. When you click the Knit button a document will be generated that ... [Read more...]

De-duplicating clinic visits

November 25, 2019 | Nathan Green

Problem We want to only keep an individual’s clinic visits which are for new infections.Therefore, want to remove repeat visit to the clinicwhere a repeat is defined as within 6 weeks of the previous visit. Solutions There are a number of way to tackle this problem which vary in ... [Read more...]

R Programming for Public Policy Analysis

November 25, 2019 | Giles

Early in 2019 I posted a short ‘listicle’ with some of the key reasons I think Python and/or R should become essential tools in a modern policy analyst’s toolkit. The full article is here, but the headline points I in the article were; R programming’s use across disciplines ... [Read more...]

Another mixed effects model visualization

November 25, 2019 | Higher Order Functions

Last week, I presented an analysis on the longitudinal development of intelligibility in children with cerebral palsy—that is, how well do strangers understand these children’s speech from 2 to 8 years old. My analysis used a Bayesian nonlinear mixed effects Beta regression model. If some models are livestock and some ...