An X’idated reader of Monte Carlo Statistical Methods had trouble with our Example 3.13, the very one our academic book reviewer disliked so much as to “diverse a 2 star”. The issue is with computing the integral when f is the Student’s t(5) distribution density. In our book, we compare a few importance sampling solutions, 
Visualization is a key to success in regression analysis. This is one of the (many) reasons I am also suspicious when I read an article with a quantitative (econometric) analysis without any graph. Consider for instance the following dataset, obtained from http://data.worldbank.org/, with, for each country, the GDP per capita (in some common currency) and the infant mortality rate...
FastRWeb is an infrastructure that allows any webserver to use R scripts for generating dynamic content, such as web pages and graphics. In this post, you’ll learn how to install and set up FastRWeb on a Mac. This tutorial is expendable to any Unix-like operating system. It is an adaptation from Jay Emerson’s post, Setting
There seems to be a scale that’s tipping at the moment: Data or code that should be published* is often not. This should seem like an odd statement for anyone in science, but it should be easy to show that most publications … Continue reading →
If you missed this morning's webinar, Revolution R Enterprise, 100% R and More, I've embedded the slides below. Interestingly, about half of today's participants were SAS users, and the remainder R users. The first section introduces open-source R, and the second describes the additional features of Revolution R Enterprise. View more presentations from Revolution Analytics Unfortunately we had a...
Apparent Reason, my new monthly podcast, is a boisterous and non-technical discussion of economics and statistics. In that format I don't have the luxury of showing charts and graphs to complement my discussion, so I use the playitbyr package to represent the data as sound. (Apparently February is a great month to start R-related podcasts!
I’ve just released my first R package! Over the past 1.5 years or so, I’ve been studying an obscure statistical model over ranking (full, or partial) data called Mallows’ model. It hypothesizes that a set of sequence data has a “modal” sequence about which the data cluster, and that the data fall away from that 
There are different algorithms to calculate the Principal Components (PCs). Kurt Varmuza & Peter Filzmozer explain them in their book: “Introduction to Multivariate Statistical Analysis in Chemometrics”.I´m going to apply one of them, to...
This is a very quick post just to share a quick tip on how to add non overlapping labels to a scatterplot in ggplot using a great package called directlabels. The trick is to make each point a single member group using an aesthetic like colour and then apply the direct.label function with the first.qp … Continue reading...
Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).
