Publications by xi'an

Lack of confidence [revised]

21.04.2011

Following the comments on our earlier submission to PNAS, we have written (and re-arXived) a revised version where we try to spell out (better) the distinction between ABC point (and confidence) estimation and ABC model choice, namely that the problem was at another level for Bayesian model choice (using posterior probabilities). When doing point...

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Statistical analyses using R

22.04.2011

Another book I received from the Short Book Reviews section of the International Statistical Review is Everitt’s and Hothorn’s Handbook of statistical analyses using R. Here is a [blog-ified] version of my book review. This book is the second (blue) edition of a successful (violet) handbook that can benefit a wide audience interested in using...

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Bayesian job in Cambridge

26.04.2011

Here is an email that could appeal to some readers: Job in Cambridge MRC-BSU – Bayesian statistician Career development fellow MRC Biostatistics Unit, Cambridge We are offering an exciting opportunity to work on Bayesian models for infectious disease dynamics. A statistician is required to contribute to a programme of research to develop infer...

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Postdoc on adaptive MCMC in Paris

02.05.2011

Although the official deadline is long past, I just became aware of this call for a postdoctoral position in Paris starting next Fall. Please feel free to apply: Summary Adaptive Markov Chain Monte Carlo (MCMC) methods are currently a very active field of research. MCMC methods are sampling methods, based on Markov Chains which are ergodic with ...

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Another review of Introducing … R

02.05.2011

The March 2011 issue of JASA contains a review of Introducing Monte Carlo Methods with R by Hedibert Lopes. As in the previous review, the poor quality of the figures is (rightly) pointed out by Hedie. However, the main message of the review remains very positive and, furthermore, Hedie advertises the ‘Og itself in the review! E.g., Another dy...

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Invisible blogs!

04.05.2011

Julien just signaled an intermitent disappearance of the posts on the ‘Og, depending on the operating system: Ubuntu 10.10 seems to be working (most of the time!) while Mac and Windows are having problems… This is beyond my abilities, I have contacted WordPress support, maybe they are working on some new feature, maybe I once again incorporat...

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Cuckoo eggs

06.05.2011

In Tangente n⁰42, there was a [Latter, 1902] dataset about the size of cuckoo eggs against the species (goldcrest and warbler) which built the nest. (The whole dataset from Latter is analysed in Maindonald and Braun’s Data Analysis and Graphics Using R, with a degree of caution about how trustworthy this data is…) This is an old reference, ...

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Problems with plyr — the memory/complexity trade-off

10.05.2011

Two types of R users My overwhelming impression from UseR 2010 is that, generally speaking, there are 2 types of regular R users — those who have heard and are made uncomfortable by the idea of the *apply() functions, and those who really get it. In UNM R programming group that I’ve been leading for about a year now, I’ve really tried to g...

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ABC model choice by DIC

10.05.2011

Yet another paper on ABC model choice was posted on arXiv a few days ago, just prior to the ABC in London meeting that ended in the pub above (most conveniently located next to my B&B!). It is written by Olivier Francois and Guillaume Laval and the approach relies on DIC for running model selection. Although I disagree with the reasons given for ...

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The confusing gamma parameter

13.05.2011

Boris from Ottawa sent me this email about Introducing Monte Carlo Methods with R: As I went through the exercises and examples, I believe I found a typo in exercise 6.4 on page 176 that is not in the list of typos posted on  your website.  For simulation of Gamma(a,1) random variables with  candidate distribution Gamma([a],b), the optimal ch...

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