This morning, I noticed that none of my R related posts had appeared on R-bloggers for the past fortnight… After investigating, this was caused by…cut-and-paste! Indeed, when advertising about the special issue of TOMACS Arnaud Doucet and I edit about Monte Carlo methods in Statistics, I copied the main ... [Read more...]

In recently years, high-throughput experimental techniques such as microarray and mass spectrometry can identify many lists of genes and gene products. The most widely used strategy for high-throughput data analysis is to identify different gene clusters based on their expression profiles. Another commonly used approach is to annotate these genes ... [Read more...]

I’m currently writing some lecture notes on R and I used the phrase “a R package” without thinking. Since the word following the article “a” was a consonant, I automatically went for “a” instead of “an”. The problem is that “R” sounds likes a vowel, so “a R package” ... [Read more...]

The version 0.22 of solaR is now available at CRAN. Besides, solaR is now registered at R-Forge. A new mergesolaR method has been defined for merging solaR objects. The calculation of the sunset time has been improved. The voltage dependency of the efficiency curve of the inverter is now included in ... [Read more...]

This is the third post in the Backtesting in Excel and R series and it will show how to backtest a simple strategy in R.  It will follow the 4 steps Damian outlined in his post on how to backtest a simple strategy in Excel.Step 1: Get the dataThe ... [Read more...]

The mathematical puzzle from the weekend edition of Le Monde from a few weeks ago was not too hard to solve by induction but my R code failed miserably! The puzzle was as follows: A calculator is broken in such a way that it starts by exhibiting 0, then pressing 4, 6 or 0 ... [Read more...]

[UPDATE 3/28/2011: Fixed an enormous bug in the R code.] I’m trying to collect data sets that showcase how the classical statistical distributions appear in modern contexts. I’ve already got some data that shows how the gamma distribution appears in video game scores, and now I’m hoping to ... [Read more...]

News of the latest release of Aquamacs, version 2.2, appeared this week in my echo area. Given the opportunity to procrastinate, I dropped everything and upgraded; returning to work, I noticed that the version of ESS shipped with Aquamacs 2.2 is ESS 5... [Read more...]

The RInside package makes it pretty simple and straightforward to embed R, the wonderful statistical programming environment and language, inside of a C++ application. This uses both the robust embedding API provided by R itself, and the higher-level... [Read more...]

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Sometimes you are facing time series which has both date and time property in one column in CSV file. In this case you need to pass additional parameter into read.zoo function:   View Code RSPLUS1 z [Read more...]

This all began with an introductory presentation about social network analysis to a group of medical students.  What better way to grab their attention than with attractive, fake doctors having sex on television?  Naturally this led to the dense network … Continue reading → [Read more...]

I received this email last week from Ian Langmore, a postdoc in Columbia: I’m looking for literature on a subject and can’t find it:  I have a Metropolis sampler where the acceptance probability is evaluated with some error.  This error is not simply error in evaluation of the ... [Read more...]

This is not my daily blogpost, but something I found while searching for different plots just copy this code and post it in your Rserve (or what you use to give in R commands) install.packages("onion") require(onion) data(bunny) p3d(bunny,theta=3,phi=1... [Read more...]

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I promise this is my last post on the now week and a half old π pay! Building on the last post, I figured I could show how convergence actually works in the estimation algorithm. If you’ll recall, we plotted … Continue reading → [Read more...]

The recently announced Revolution Analytics / Zementis partnership goes a long way towards demonstrating how R fits into big-league production environments. A frequent complaint against R is that although R is fine prototyping tool it is not able to handle production environments. Well, that’s just not true. In fact, it ... [Read more...]

According to the Google Ngram corpus, R is still the top rated statistical software package. Ok, I’m just kidding. That plot is worthless. All the data are from books published between the years 1890 and 2008, and none of those software packages wou... [Read more...]

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I blame Rully for this. If it wasn’t for him I wouldn’t have been obsessed with this and spent a good few hours at night figuring it out last week. It all started when Rully mentioned that he knew how many beeps there are in the Singapore MRT (... [Read more...]