# Monthly Archives: August 2011

## le logiciel R

August 24, 2011
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For once, here is a book review I wrote in French about the book Le logiciel R, written by Pierre Lafaye de Micheaux (Université de Montréal), Rémy Drouilhet (Université de Grenoble 2) and Benoît Liquet (Université de Bordeaux 2): Ce livre édité par Springer (dans la même collection que Le Choix Bayesien) propose une couverture

## The Open Governance Index: Results for The R Project

August 24, 2011
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Just over two weeks ago, I invited readers to complete the Open Governance Index (OGI) Questionnaire regarding The R Project. The OGI evaluates several facets of governance in open source projects (OGI publication). The OGI questionnaire is reproduced below, and each question is linked from the table of useR responses. The table below presents the

## Estimating a normal mean with a cauchy prior

August 24, 2011
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The setup When doing statistics the Bayesian way, we are sometimes bombarded with complicated integrals that do not lend themselves to closed-form solutions. This used to be a problem. Nowadays, not so much. This post illustrates how a person can...

## Another Rchievement of the day

August 24, 2011
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Time for another Rchievement of the day. This is a neat little example demonstrating the power of control flow (type ?Control in R to find out more). But perhaps a not-so obvious way of using it. So what does this … Continue reading →

## The problem with R? Too much new stuff!

August 23, 2011
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In a tongue-in-cheek post at the Information Management blog, Steve Miller shares his "frustration" with R: package developers keep on releasing new functionality for R that makes his own work obsolete. For example, there's now pre-packaged functionality in R for enhanced dotplots, Economist-style graphics, additive regression models and more, which all obviate the need for Steve to implement such...

## expectation-propagation and ABC

August 23, 2011
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$expectation-propagation and ABC$

“It seems quite absurd to reject an EP-based approach, if the only alternative is an ABC approach based on summary statistics, which introduces a bias which seems both larger (according to our numerical examples) and more arbitrary, in the sense that in real-world applications one has little intuition and even less mathematical guidance on to

## Data manipulations

August 23, 2011
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In the last Utah R Users group meeting I gave a presentation on data manipulations on R, and today I found through the plyr mailing list two commands that I was previously unaware of that should definitely be made mention of, arrage and mutate.

## Z-Tests: Should we even bother?

August 23, 2011
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Should statistical teachers continue to teach z-tests?vote:  save z-test, or stop z-testLooking at textbooks, articles and general research I cannot remember the last time I saw someone use a z-test in a study. I have seen many a t-test, ANOVA, ch...

## Graphically analyzing variable interactions in R

August 23, 2011
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I studied Ecology as an undergraduate, which meant I spent a lot of time gathering and analyzing field data. One of the basic tools we used to look for relationships in a large set of variables was correlation and scatterplot matrices. Each of these ...

## Accelerating path-dependent loops: A quick Rcpp case study

August 23, 2011
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User BobH asked on StackOverflow about accelerating path-dependent loops. He provided a simple example in which a vector gets filled conditional on the value of the preceding element. Simple to code, but hard to vectorise. By the time I saw that q...