I’m in the process of buying a used car. Since I enjoy making these decisions as complicated as possible, I’ve written some R code to scrape relevant websites for informative data. I’ve written this up as a blog entry because I think it’s a decent example of how one might use the XML...
This file illustrates the computer code to use spatial filtering in the context of Bayesian Model Averaging (BMA). For more details and in case you use the code please cite Crespo Cuaresma and Feldkircher (2010). In addition, this tutorial exists as ...
Handling large dataset in R, especially CSV data, was briefly discussed before at Excellent free CSV splitter and Handling Large CSV Files in R. My file at that time was around 2GB with 30 million number of rows and 8 columns. Recently I started to collect and analyze US corporate bonds tick data from year...
ables are pretty common in web pages as data sources, and the most direct way to get these data is probably to copy and paste. This is OK if there are only two or three tables, and when we need to grab 5000 tables in 1000 web pages, we may not really wish to fulfill
Thanks to its use of Apple's vecLib for BLAS, LAPACK and related functions, the open source distribution of R performs many matrix calculations 2-10X faster than Revolution Analytics Community edition on Mac OS X systems.
Recently I had the opportunity to do a job swap with one of the guys in the laboratory here at HSL. I helped out with the mass-spectrometry and James helped me with the data analysis. Two very useful things came out of this. Firstly, it’s been very informative to see how the data I get 
For over a year now, i've been collecting how much time i spend in computer and how much of it is actually used in creative/productive activities. By productive activity i mean that the time spent in text editor(emacs), terminal, excel or a datab...
The winners of this year's ggplot2 case study competition have been announced. I was honoured to be asked to be a judge of the competition this year, but it was a difficult job with so many excellent entries. In the end, the judging panel (which included Heike Hoffman and Hadley Wickham and me) selected three entries which each demonstrated...
Fringe provides an excellent example of cointegration. This is a television show in which there are two adjacent universes. The universes are almost alike but not exactly. Now, everyone knows that history is chaotic. If a butterfly does an extra flap of its wings, then that difference spreads out to change subsequent events everywhere. But … Continue reading...
After recently discovering the excellent methods section on mappingonlinepublics.net, I decided it was time to document my own approach to Twitter data. I’ve been messing around with R and igraph for a while, but it wasn’t until I discovered Gephi that things really moved forward. R/igraph are great for preprocessing the data (not sure how
Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).
