Publications by xi'an
Le Monde puzzle #13
This week, Le Monde offers not one but three related puzzles: Is it possible to label the twelve edges of a cube by consecutive numbers such that the sum of the edge numbers at any of the eight nodes is constant? Is it possible to label the eight nodes of a cube by consecutive numbers such that the sums of the node numbers over the edges are all...
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Mixtures in Madrid (3)
For my second lecture today, I need to plot a likelihood surface for a basic two-component mixture with only the means unknown: here is the R code to speed up things llsurf=function(trumyn=2.,wayt=.3,var2=1.,ssiz=500){ # draws the log-likelihood surface and a random sample sd2=sqrt(var2) parti=(runif(ssiz)>wayt) sampl=(1-parti)*rnorm(ssiz)+parti*...
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Thomas Bayes, 250 years later
A link on R-bloggers signaled a series of blogs and videos by IBM Netezza about Thomas Bayes and the consequences of his theorem. Which made me realise this was indeed the 250th anniversary of his death, and that maybe we (as a collective, incl. ISBA) should have done something on April 17th… Before the Revolution Analytics announcement, only t...
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Lack of confidence [revised]
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
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
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
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
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!
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
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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