[Read more...]

I've been playing with images recently, probably inspired from my trip in San Francisco. There was an exhibit at the De Young museum of fine arts with pieces borrowed from the Musée d'Orsay. I did not go to the exhibit because it is easy enough fo... [Read more...]

An exciting conference in Zurich next February, 02-05. (I think I will attend! And not for skiing reasons!) Latent Gaussian models have numerous applications, for example in spatial and spatio-temporal epidemiology and climate modelling. This workshop brings together researchers who develop and apply Bayesian inference in this broad model class. ... [Read more...]

“Fast, cheap, correct: Pick two.” Does this phrase apply to statistical matching algorithms? In the case of Optmatch, you can have all three. “Cheap” is easy: it is open source. You can download it for free. Today I’m going to explain how to make the matching process both faster ... [Read more...]

This post sets out how to calculate confidence intervals for correlations using R. Because I often get this question from people unfamiliar with R, it assumes no prior knowledge of R. Formulas Online Statsbookhas formulas for calculating the confiden... [Read more...]

The new version 0.2.9 of RcppArmadillo has been uploaded to CRAN. The only change is an update of the included Armadillo template library to version 0.9.92 which Conrad released this week. RcppArmadillo makes it easy to write highly efficient and hi... [Read more...]

Today is Veterans Day in the US, and Remembrance Day or Armistice Day elsewhere in the world. Whatever you know this day as, it's a day for remembering the sacrifices of those who served. Drew Conway has commemorated the day in a touching yet saddening way, by visualizing with R ... [Read more...]

You might recall we posted a couple of weeks ago this chart summarizing the times of the day Firefox users switch on Private Browsing mode: The chart, based on data from the Mozilla Test Pilot program tells an interesting story about the habits of Web users. But what other interesting ... [Read more...]

In the mixed effects regression for all 10 countries in the research I mentioned previously on this blog http://stevepowell99.posterous.com/which-parents-are-satisfied-with-their-childs, while school mean of "parents believing their represen... [Read more...]

[Read more...]

Mortgage rates have been at historic lows recently.  The rates are posted various places online along with simple mortgage calculators.  Such calculators illustrate the payment schedule for a mortgage based upon selected terms. But with less ... [Read more...]

[This article was first published on Rmetrics blogs, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share your [Read more...]

Steve McNally of the Forbes Mean Business blog says R is a name you need to know for 2011. He cites some great examples of R in action: Facebook has used R to figure out that “just two data points are significantly predictive of whether a user remains on Facebook: (i) ... [Read more...]

Prof. Chris Fonnesbeck briefly introduces Bayesian inference, then discusses how to estimate Bayesian models with Markov Chain Monte Carlo using PyMC. PyMC is the premier Python package for doing MCMC estimation, and Prof. Fonnesbeck is one of the pac... [Read more...]

At last... I have been suffering with XEmacs displaying odd characters instead of the quotation marks that are used in R help files. This was driving me up the wall because it makes the files (and R output in general) very hard to read; however, I fina... [Read more...]

As part of my on-going research simulating network structure using graph motifs I have been collecting novel data sets to test and benchmark the method. Since I am a political scientist studying conflict, it was suggested to me to collect a co-authorship network within this sub-discipline. Such a network is ... [Read more...]

Here and there, I mentioned two codes to generated quasiPoisson random variables. And in both of them, the negative binomial approximation seems to be wrong. Recall that the negative binomial distribution is where and in R, a negative binomial di... [Read more...]

'Indeed, I am moving on: my new project is about methods on how to domesticate the unknown, exploit randomness, figure out how to live in a world we don't understand very well. While most human thought (particularly since the enlightenment) has focused us on how to turn knowledge into decisions, ... [Read more...]

I’ve had a few emails lately about forecast evaluation and estimation criteria. Here is one I received today, along with some comments. I have a rather simple question regarding the use of MSE as opposed to MAD and MAPE. If the parameters of a time series model are estimated ... [Read more...]

Following the posting on arXiv of the Statistical Science paper of Carvalho et al., and the publication by the same authors in Bayesian Analysis of Particle Learning for general mixtures I noticed on Hedibert Lopes’ website his rejoinder to the discussion of his Valencia 9 paper has been posted. Since the ... [Read more...]