## AISTATS 2016 [post-decisions]

Posted in Books, pictures, Statistics, Travel, University life with tags , , , , , , , , , , , on December 27, 2015 by xi'an

Now that the (extended) deadline for AISTATS 2016 decisions is gone, I can gladly report that out of 594 submissions, we accepted 165 papers, including 35 oral presentations. As reported in the previous blog post, I remain amazed at the gruesome efficiency of the processing machinery and at the overwhelmingly intense involvement of the various actors who handled those submissions. And at the help brought by the Toronto Paper Matching System, developed by Laurent Charlin and Richard Zemel. I clearly was not as active and responsive as many of those actors and definitely not [and by far] as my co-program-chair, Arthur Gretton, who deserves all the praise for achieving a final decision by the end of the year. We have already received a few complaints from rejected authors, but this is to be expected with a rejection rate of 73%. (More annoying were the emails asking for our decisions in the very final days…) An amazing and humbling experience for me, truly! See you in Cadiz, hopefully.

## Do we need…yes we do (with some delay)!

Posted in Books, Statistics, University life with tags , , , , , , on April 4, 2013 by xi'an

## In praise of the referee (2)

Posted in Statistics, University life with tags , , , , , , on May 24, 2012 by xi'an

Following Nicolas’ guest-post on this ‘Og, plus Andrew’s and mine’s, we took advantage of Kerrie Mengersen visiting Paris to write a common piece on the future of the refereeing system and on our proposals to improve it from within. Rather than tearing the whole thing down. In particular, one idea is to make writing referees’ reports part of the academic vitas, by turning them into discussions of published papers. Another one is to achieve some training of referees, by setting refereeing codes and more formalised steps. Yet another one is to federate reports rather than repeating the process one journal at a time for the unlucky ones… The resulting paper has now appeared on arXiv and has just been submitted (I am rather uncertain about the publication chances of this paper, given it is an opinion column, rather than a research paper…! It has already been rejected once, twice, three five times!)

## Do we need…not yet!

Posted in Books, Statistics, University life with tags , , , , , on June 10, 2011 by xi'an

Following rejections of our discussion paper of Murray Aitkin’s book, Statistical Inference, written with Andrew Gelman and Judith Rousseau, by the journals Bayesian Analysis [where I think it truly belonged, being more than a book review, an assessment of the relevance of the approach from a Bayesian viewpoint!], JASA Book Reviews, and Electronic Journal of Statistics, we have decided to try yet another outlet for our discussion, Statistics and Decisions, to which I had not submitted a paper in about twenty years (since the loss of an accepted paper with George Casella by the S&D editor at the time!). More fundamentally, I completely understand and acknowledge the individual decision by each editorial board not to publish our piece in their respective journals, but I bemoan (once again) the lack of outlet for this type of opinion tribune that should appeal to the community as a whole (again, because this is a book that aims at a complete shift in or out of the  Bayesian theory!) and that should be possible given the current electronic communication tools. In other and more precise words, journals should start blogs or forums where readers could comment on published papers and, why not?!, rejected authors could respond to reviews… This is why I liked the format of the review process in the journal Hydrology and Earth System Sciences. that allows for a publication of referee’ reports and comments from the readership. In any case, I hope Statistics and Decisions will be interested in our piece as we are about to run out of options and stamina! (I usually give up much earlier than that!)

## Keynes’ review quickly rejected

Posted in Books, Statistics, University life with tags , , on April 8, 2010 by xi'an

Yesterday morning, I submitted my review of Keynes’ A Treatise On Probability to Statistica Sinica and I got a rejection reply with the reason

(X) narrowly focused and the readership is likely to be very limited.

this morning. Fine, I understand the point and appreciate the quick return (even though I now worry about the overall publishability of the review).

## Savage-Dickey rejected

Posted in Statistics, University life with tags , , , , on January 16, 2010 by xi'an

Our Savage-Dickey paper has been rejected by the Annals of Statistics, for being too obscure. I completely understand the Editor’s perspective that this resolution of ours has very little bearing on statistical practice and on the community as a whole (“the readership at large”, as I used to write for Series B). But I fear both screeners have missed the main point of our paper which is that papers and books using the Savage-Dickey ratio all start with an assumption that does not make sense from a measure-theoretic point of view… One screener argued that our point is moot, given that everyone agrees on the same version of the density, as otherwise “would even a likelihood function be properly defined?” But this is not true: a likelihood

$\ell(\theta|x)=f(x|\theta)$

is the value of the density at the observed value of the random variable. Since this observed value is by nature random, it is not possible to define a specific version of the density function at x… This may alas be related with the progressive disappearance of measure-theory from the Statistics programs: when my third year exchange students go abroad, it is rarer and rarer to find a place that offers Measure Theory at a level lower than a PhD course.

## Another slice

Posted in Statistics with tags , , , , on January 7, 2010 by xi'an

No this is not yet another post-Christmas/NY ‘Og entry about food! Ian Murray, Ryan Adams and David MacKay posted a small piece on arXiv on Tuesday where they advocate a new type of slice sampler in cases when the posterior distribution on the parameter $f$ is associated with a Gaussian prior,

$\pi(f|x) \propto \mathcal{N}(f|0,\Sigma) L(f|x)$

and where the update in the Markov chain is based on an elliptic update,

$f^\prime = f \cos \theta + \nu \sin\theta,\quad\nu\sim\mathcal{N}(0,\Sigma)$,

except that $\theta$ is also updated at each MCMC step by a slice sampler. The resulting algorithm is a slice sampler in that it does not reject new values of $f^\prime$.

I find the proposal interesting, especially because it incorporates a “cyber-parameter” like $\theta$ within the Markov chain, but I wonder how widely the efficiency of the algorithm persists. Indeed, simulating from the prior cannot be very efficient when the likelihood strongly differs from the Gaussian prior. A lack of rejection is not a positive property per se and Gibbs sampling (incl. slice sampling) is notoriously slow for this very lack…