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) having more than one session as a new...
Monthly Archives: November 2010
Bayesian estimation with Markov Chain Monte Carlo using PyMC
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...
Quantitative Ecology 2010-11-10 14:56:00
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...
Quantitative Ecology 2010-11-10 14:56:00
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...
Co-authorship Network of SSRN Conflict Studies eJournal
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 useful for several reasons;
Generating a quasi Poisson distribution, version 2
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...
Don’t be a Turkey
'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, my new mission is to...
Don’t be a Turkey
'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, my new mission is to...
Forecast estimation, evaluation and transformation
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 by minimizing MSE, why do we
Particle learning [rejoinder]
![Particle learning [rejoinder]](http://www.r-bloggers.com/wp-content/uploads/2010/11/bpl1c5no-n10000.jpg?w=360&h=360)
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 discussion involved several points 
Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).
