1 Introduction Rarely have I seen a three dimension graph including time, value, and volatility. It is essenti

A few days ago I had blogged about getting NumPy data in R by using a simple converter script. That works fine, but it is a little annoying to have to write an entire file only to read from it again. So I kept looking around for a better solution---and soon found the cnpy library by Carl Rogers which provides simple C++...

The Actuary Puzzle 508 - Square numbers Author: Matt Malin From the puzzle pages of The Actuary June 2012, I attempt to solve the following, making use of R: This square contains exactly 21 smaller squares. Each of these smaller squares has sides of integer length, with no two smaller squares having sides of the same length. Can you find a solution for...

About this time last month, I attended the 2012 UseR! Meeting. Now an annual event, this series of conferences started in Europe in 2004 as an every-other-year gathering that now seems to alternate between the U.S. and Europe. This year’s meeting was held on the VanderbiltUniversity campus in Nashville, TN, and it was attended by about 500 R aficionados,...

Welcome to this demo of how R code and results can be combined into an HTML report. This entire blogpost was generated by using a combination of R, knitr and markdown. Beforehand, make sure you have the following libraries installed (latest version); knitr markdown ggplot2 (to run the example script) Read more »

Going to supper in 20 minutes. I’d like to type down my solution to the 12th Euler problem, just make my time count. The sequence of triangle numbers is generated by adding the natural numbers. So the 7th triangle number … Continue reading →

As first reported by Paolo, the new R journal is out! You can Download the complete issue from here. Refereed articles may be downloaded individually using the links below. Table of Contents Editorial 3 Contributed Research Articles Analysing Seasonal Data Adrian G Barnett, Peter Baker and Annette J Dobson 5 MARSS: Multivariate Autoregressive State-space...

The biggest prize in UK soccer, the Premier League Championship, is decided by a points system. Unlike most sports competitions, there's no final round or playoff series: once the regular round of games is complete, the team that has accumulated the most points (three for a win, and one for a draw) is the champion of English football. In...

One of the great things about Twitter is that it’s a global conversation anyone can join anytime. Eavesdropping on the world, what what! Of course, it gets even better when you can mine all this chatter to study the way humans live and interact. For example, how do people in New York City differ from those in Silicon Valley? We...

Earlier this year I doodled a recipe for comparing the folk commonly followed by users of a couple of BBC programme hashtags (Social Media Interest Maps of Newsnight and BBCQT Twitterers). Prompted in part by a tweet from Michael Smethurst/@fantasticlife about generating an ESP map for UK politicians (something I’ve also doodled before – Sketching

We look at volatility clustering, and some aspects of modeling it with a univariate GARCH(1,1) model. Volatility clustering Volatility clustering — the phenomenon of there being periods of relative calm and periods of high volatility — is a seemingly universal attribute of market data. There is no universally accepted explanation of it. GARCH (Generalized AutoRegressive … Continue reading...

Counting cells under microscope is always laborious and null. Those in the art would be relieved with assistance of a powerful image processing package, EBImage. Images are treated as “Image” objects, essentially multi-dimensional arrays. The class “Image” contains spatial information, pixel … Continue reading →

Those that do a lot of nonlinear regression will love the nls function of R. In most of the cases it works really well, but there are some mishaps that can occur when using bad starting values for the parameters. One of the most dreaded is the “singular gradient matrix at initial parameter estimates” which

Leipzig R Statistical Computing is the sixth local R user group in Germany, and has been holding meetings since February. In the next meeting on July 12, member Claudia Beleites will talk about her pacakges softclassval (for classifier performance measures) and hyperspec (for hyperspectral data). meetup.com: Leipzig R Statistical Computing

I currently program an automated report generation in R – participants fill out a questionnaire, and they receive a nicely formatted pdf with their personality profile. I use knitr, LaTex, and the sendmailR package. Some participants did not provide valid email addresses, which caused the sendmail function to crash. Therefore I wanted some validation of

As more and more data go online (plus we love Google Drive) we are forced to connect to our data over the net. We mostly do this via RCurl (but we could do this using RGoogleDocs as well).In that case all that is required to get the data into R is the two lines of

As more and more data go online (plus we love Google Drive) we are forced to connect to our data over the net. We mostly do this via RCurl (but we could do this using RGoogleDocs as well).In that case all that is required to get the data into R is the two lines of ...read more