Apples, oranges, pears or bananas? Bus, train, car, or walk? Many choices are made between more than two options, a situation that can be represented by multinomial choice modelling. Here's a quick tutorial on how to do it in R. [Read more...]

Imagine you have to analyze text comprising 18,000 words. You have to identify the most commonly cited ideas or words in the text and then present the analysis in a graphic format. There are sophisticated tools out there to help you with this task, but then again there is a tight ... [Read more...]

Vectors are a basic data structure in R and are created using the c() function. Unlike data frames and lists, the elements of a vector must be of the same mode. Functions can be used on a vector. For example, length(x) can be used to find the number of ... [Read more...]

All my recent plots are built using ggplot2 package. I don’t know if my dear readers have noticed the difference, but from my point of view, ggplot2 allows to create nice looking and aesthetics plots. I was using this package before, but the real boost came after reading this ... [Read more...]

I recently wrote an email with an attached LZMA archive. It was immediately answered with something like: "What are you doing? I had to boot linux to open the file!" First of all I don't care whether user of proprietary systems are able to read open formats, but this answer ... [Read more...]

Dirk Eddelbuettel has recently released RQuantLib-0.3.7, which contains the necessary QuantLib builds to allow the CRAN servers to build the Windows binary.This (thankfully) makes my post on how to build RQuantLib on 32-bit Windows unnecessary for casu... [Read more...]

I am a recent comer to twitter, and it took me a few weeks to figure out what this was all about. Who are all these people tweeting each other and what do all these trending hashtags mean? Do these … Continue reading → [Read more...]

To install the community nodes in knime: help __ install new software __ http://tech.knime.org/update/community-contributions/release you’ll only need the “R and Groovy scripting extensions for KNIME” What is it and what does it... [Read more...]

First, go take a look at this website: http://rgg.r-forge.r-project.org/docs.html At “6. RGG Elements” you can see which GUI elements you can give to the user and which functions they have. Then, open a textfile and call it however you want... [Read more...]

A build-fix release RQuantLib 0.3.7 is now on CRAN and in Debian. RQuantLib combines (some of) the quantitative analytics of QuantLib with the R statistical computing environment and language. Thanks to the help by Brian Ripley (who compiled Quan... [Read more...]

Conrad Sanderson made a bug-fix release (1.1.92) by for his wonderful Armadillo templated C++ library for linear algebra appeared yesterday and as usual a new release 0.2.18 of RcppArmadillo, our Rcpp-based integration into R is now on CRAN mirrors. ... [Read more...]

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The Atmospheric Science Data Center (ASDC) at NASA Langley Research Center offers several data sources. For example, it is possible to download a text file with the 22-year (July 1983 – June 2005) monthly and annual average of global horizontal irradiation. nasafile [Read more...]

A violin plot is a combination of a boxplot and a kernel density plot. Lattice includes the panel.violin function for this graphical tool. This example draws a violin and a boxplot together. First, let’s download some solar radiation data from the NASA webpage: nasafile [Read more...]

As Jian-Feng rightly pointed out in a comment on my guide to setting up snow on the OSC cluster, it was probably somewhat cavalier of me to say: Getting snow to run properly on single machines, or ever with a cluster of … Continue reading → [Read more...]

Last week Jack Edwards raised the fact that Milan Lucic was the first Bruin player to join the 30 Goal / 100 Penalty Minute club in a few years.  It got me thinking about the other players who have accomplished … Continue reading → [Read more...]

I am a big Boston Bruins fan and have enjoyed the ups and downs over the last few years, regardless of the catastrophes that have occurred during the playoffs.  The team struggled a few weeks ago, but have recently seemed … Continue reading → [Read more...]

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