I ran a across a strange bug in R recently. Like all the best programming languages, R treats functions as first class objects. That is to say that functions can be passed as arguments and return values from functions, named as variables, and, while not part of the strict definition of first class...
I've shown several examples of how to use LSPM's probDrawdown function as a constraint when optimizing a leverage space portfolio. Those posts implicitly assume the probDrawdown function produces an accurate estimate of actual drawdo...
is maps and geographical data representation in R. In case you’re curious too this is a good study material from R-Bloggers : maps ; geographical ; spatial Ok. This could be a tweet rather than a post…
Jack Germain of LinuxInsider interviewed Revolution CEO Norman Nie for his "Startup to Watch" column. Amongst the topics covered: the R language (Norman: "There are no statistical expressions that can not be written in R"), Revolution's recent name-change and announcement of our development roadmap, and the challenges of competing with SAS and Norman's former company, SPSS. Read the full...
On December 11, 2006 Felipe Calderon, as the first significant act of his presidency, sent the army to his home state of Michoacan. He claimed that it was to regain control of territories lost to the drug cartels, and indeed, a new cartel had started operating in Michocan. But the fact that he won the election by the slim margin of...
On December 11, 2006 Felipe Calderon, as the first significant act of his presidency, sent the army to his home state of Michoacan. He claimed that it was to regain control of territories lost to the drug cartels, and indeed, a new cartel had started operating in Michocan. But the fact that he won the election by the slim margin of...
In case you missed them, here are some articles from last month of particular interest to R users. We linked to 13 videos for learning R, from the basics ("What is R?") to more advanced topics. We noted the release of R 2.11.1. We announced that Revolution Analytics makes its software available free of charge to the academic community....
As per request, here is the code that I wrote to draw bifurcation plots in R. Bifurcation diagrams for discrete maps can be done using this code by James Jones. It is a little easier since approximation is not needed. In the following code, I used the deSolve library to draw bifurcation diagrams for a 
The Deepwater Horizon Incident is in the U.S. headlines and on many peoples minds. The folks over at Revolution Analytics were even discussing this subject today. Several government sites including the NOAA have sections dedicated to the problem. In...
I really enjoyed all four talks at today's online conference, Making Data Work. (Disclosure: Revolution sponsored this conference.) I thought the four speakers together gave a great overview of issues related to the processing, analysis, and visualization of big data. Mike Driscoll started off with a useful categorization for data size. "Small Data" (<10Gb) fits in the memory of...
Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).
