In our data-science class, after discussing limitations of the logistic regression, e.g. the fact that the decision boundary line was a straight line, we’ve mentioned possible natural extensions. Let us consider our (now) standard dataset clr1 [Read more...]

Nathan Uyttendaele has written a great beginner’s guide to speeding up your R code. Abstract: Most calculations performed by the average R user are unremarkable in the sense that nowadays, any computer can crush the related code in a matter … Continue reading → [Read more...]

A kind reader directed me in a comment on Experiments in Time Series Clustering to this paper. Clustering of Time Series Subsequences is Meaningless: Implications for Previous and Future Research Eamonn Keogh  and Jessica Lin Computer Science & Engineering Department University of California – Riverside http://www.cs.ucr.edu/~eamonn/meaningless.... [Read more...]

by Joseph Rickert R user group activity is still on the rise. The following plot of the number of R user group meetings listed on Revolution Analytics' Community Calendar over the most recent 114 weeks shows a slight to upward trend along with a couple of annual cycles. Predictably, meetings trail ... [Read more...]

Mango Solutions releases version 1.0 of RapidNCA Chippenham, Wiltshire, UK – 5th March 2015 – Mango Solutions are pleased to announce the release of version 1.0 of RapidNCA, an application for the quick performance of non-compartmental analysis via a streamlined … Continue reading → [Read more...]

We will start off this first section of Part 3 with a brief introduction of the plotting system ggplot2. Then, with the attention focused mainly on the syntax, we will create a few graphs, based on the weather data we have prepared previously. Next, in Part 3b, where we will be ... [Read more...]

Workflow This post is really about workflow. Specifically a data-science workflow, although it should be relevant for others. It will probably resonate most (if at all) with those who have some experience (mostly positive) generating reports from Rmarkdown files with knitr, but might have some gripes. Maybe not gripes, maybe ... [Read more...]

Given all the attention the internet has given to the colors of this dress, I thought it would be interesting to look at the capabilities for extracting colors in R. R has a number of packages for importing images in various file formats, including PNG, JPG, TIFF, and BMP. (The ... [Read more...]

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What is DataFest? DataFest is a team competition, where a team of up to 5... [Read more...]

Data Science has its own language. So, if you want to have at least a slight chance of surviving in the enterprise world of tomorrow -with its obsessive focus on collecting and analyzing data- you better have started yesterday with learning this terminology. Luckily, and inspired by the “How To ... [Read more...]

A modular Rmarkdown workbook in action I’m now using a properly modular Rmarkdown workbook, and really quite chuffed with it! I’ve seen discussion of electronic lab notebooks for bioinformatics with only mention of org-mode for emacs users, IPython (now the Jupyter project) and the likes of Evernote/Word ... [Read more...]

By Richard Pugh – Commercial Director, (UK). As the importance of using analytics to drive decision making continues to grow at pace, so too does the need to make data science more efficient and “deployable”.  This drives many changes to … Continue reading → [Read more...]

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The paper Analysis of the Linux Kernel Evolution Using Code Clone Coverage analysed 136 versions of Linux (from 1.0 to 2.6.18.3) and calculated the amount of source code that was shared, going forward, between each pair of these versions. When I saw the heatmap at the end of the paper (see below) I ... [Read more...]

Another popular technique for classification (or at least, which used to be popular) is the (linear) discriminant analysis, introduced by Ronald Fisher in 1936. Consider the same dataset as in our previous post __ clr1 x y z df plot(x,y,pch=19,cex=2,col=clr1[z+1]) The main interest of that ... [Read more...]

JASP is an interesting project. It is based on R with additional facilities and functions such as automatic table generation. There appears to be an R package that provide that functions directly to R users. Very worth checking out. [Read more...]

In the February 2015 edition of The Journal of Finance, a well known academic paper, “The Pre-FOMC Announcement Drift”, was finally published, almost 4 years after the working paper was released in the public domain in 2011.Authored by researchers, Lucca and Moench, at the US Federal Reserve, it documents the tendency for ... [Read more...]

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