(Almost) every introductory course in probability introduces conditional probability using the famous Monte Hall problem. In a nutshell, the problem is one of deciding on a best strategy in a simple game. In the game, the contestant is asked to select one of three doors. Behind one of the doors is a great prize...
The above map (and this one) was produced using R and ggplot2 and serve to demonstrate just how sophisticated R visualisations can be. We are used to seeing similar maps produced with conventional GIS platforms or software such as Processing but I hadn’t yet seen one from the R community (feel free to suggest...
Speaking of R… On the 16th, TIOBE Software released the Tiobe Index of the most popular programming languages. For the first time ever, R is in the Top 20. The top spots are, no surprise, occupied by Java and C respectively. More after the jump. The way this index is assembled is…interesting. The full...
By following twitter’s #rstats hashtag (rss feed), I recently came across a very interesting R-related blog: datanalytics.com. The first post I read from it was about setting up an on-line reading group to go through the excellent “The Elements of … Continue reading →
For a much better looking version of this post (where code is actually readable!), see this Github repository, which also contains some of the example datasets I use and a literate programming version of this tutorial. Introduction This is a bare-bones introduction to ggplot2, a visualization package in R. It assumes no knowledge of...
This article linked below and the subsequent comments (some apparently from an Elsevier rep.) are interesting. It's not directly related to R, but is related to open source/science philosophy. Elsevier-funded NY Congresswoman Carolyn Maloney Wants to D...
RTextTools v1.3.5 addresses some key concerns that have been raised in recent months. Many of the algorithms used in RTextTools require that any new data presented to a trained classifier contain the same features as the original document-term matrix. Since this rarely (if ever) happens in the real world, I have added an originalMatrix...
I was rummaging around in the source of R looking for trouble, as one does, when I came across what I believed to be a less than optimally accurate floating-point algorithm (function R_pos_di in src/main/arithemtic.c). Analyzing the accuracy of floating-point code is notoriously difficult and those having the required skills tend to concentrate their...
This is just a quick note to wish you and your family a very healthy and happy holidays and wonderful New Year! I hope you enjoyed reading my blog and thank you for your comments and emails. Here is a short R code that implements an interesting idea from the Charting the Santa Claus...
RTextTools was updated to version 1.3.2 today, adding support for n-gram token analysis, a faster maximum entropy algorithm, and numerous bug fixes. The source code has been synced with the Google Code repository, so please feel free to check out a copy and add your own features!With the core feature set of RTextTools finalized,...
Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).