Blog Archives

Conferenza a Padova

June 16, 2010
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Conferenza a Padova

Today and tomorrow, I am attending the annual Italian statistical society meeting. While I appreciate very much the invitation, as well as the opportunity to walk through  Padova and Venezia for a short (and alas rainy!) hour on the way there (leaving home at 8am, walking in Venezia at noon!), I am rather skeptical of

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plagiarism exposed!

June 14, 2010
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plagiarism exposed!

Last morn, I had the surprise of receiving the following email: This is to inform you that the following abstract has been submitted to the 3rd International Conference of the ERCIM WG on COMPUTING & STATISTICS (ERCIM’10) Ab#: 114 Title: Goodness of Fit Via Mixtures of Beta distributions Keywords: nonparametric estimation, posterior conditional predictive p-value.

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bug in schoolmath

June 13, 2010
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bug in schoolmath

Neil Gunther has pointed out on his blog that the prime number decomposition R package schoolmath contains mistakes in the function primes, listing 1 as a prime number but also including decomposable numbers like 133 in its list of prime numbers: > primes(100,140) 101 107 111 113 123 129 131 137 > primes(50,140)  

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Stratified sampling

June 9, 2010
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Stratified sampling

The recently arXived paper of Goldstein, Rinott and Scarsini studies the impact of refining a partition on the precision of a stratified maximising/integration Monte Carlo approach. Quite naturally, if the partition gets improved, simulating points in each set of the partition can only improve the quality of the approximation, whether the problem is in maximising

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On particle learning

June 4, 2010
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On particle learning

In connection with the Valencia 9 meeting that started yesterday, and with Hedie‘s talk there, we have posted on arXiv a set of comments on particle learning. The arXiv paper contains several discussions but they mostly focus on the inevitable degeneracy that accompanies particle systems. When Lopes et al. state that is not of interest

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Vanilla Rao-Blackwellisation [re]revised

May 31, 2010
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Vanilla Rao-Blackwellisation [re]revised

Although the revision is quite minor, it took us two months to complete from the time I received the news in the Atlanta airport lounge… The vanilla Rao-Blackwellisation paper with Randal Douc has thus been resubmitted to the Annals of Statistics. And rearXived. The only significant change is the inclusion of two tables detailing computing

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Talk at CRiSM

May 30, 2010
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Talk at CRiSM

This is the talk I am giving at the workshop on model uncertainty organised by the Centre for Research in Statistical Methodology (CRiSM) at the University of Warwick, on May 30-June 1. Careful readers will notice there is not much difference with my previous talk on the topic, as I only included the Savage-Dickey slides

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A repulsive random walk

May 28, 2010
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A repulsive random walk

Matt Asher posted an R experiment on R-bloggers yesterday simulating the random walk which has the property of avoiding zero by quickly switching to a large value as soon as is small. He was then wondering about the “convergence” of the random walk given that it moves very little once is large enough. The values

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Random sudokus [p-values]

May 21, 2010
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Random sudokus [p-values]

I reran the program checking the distribution of the digits over 9 “diagonals” (obtained by acceptable permutations of rows and column) and this test again results in mostly small p-values. Over a million iterations, and the nine (dependent) diagonals, four p-values were below 0.01, three were below 0.1, and two were above (0.21 and 0.42).

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ACM Transactions on Modeling and Computer Simulation

May 20, 2010
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ACM Transactions on Modeling and Computer Simulation

Pierre Lecuyer is the new editor of the ACM Transactions on Modeling and Computer Simulation (TOMACS) and he has asked me to become an Area Editor for the new area of simulation in Statistics. I am quite excited by this new Æditor’s hat, since this is a cross-disciplinary journal: The ACM Transactions on Modeling and

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