Archive for Ottawa

a journal of the plague year [post-december reviews]

Posted in Books, Kids, pictures, Travel with tags , , , , , , , , , , , , , , , , , , , , , , , , , , , , , on February 13, 2021 by xi'an

Read a (French) novel by Fred Vargas, Sous les Vents de Neptune, after finding it in the book depository near my office. And enjoyed it very much, partly because it was partly taking place near Ottawa [which I visited many times while my wife was completing her EE Master there] and partly because of the author’s ability to make us doubt the main character and to keep the suspense tight enough for most of the book. There are a trip to Montréal to attend a concert and a journey to Detroit and back to find a lost relation, both reminding me of drives on these roads more than 30 years ago. What annoyed me though was the caricaturesque depiction of the locals, with a Québecois French that sounded overdone. Checking for a local perspective on that aspect, I found a book review in Le Devoir of 2004 sharing the reservation on that aspect, if with humour.  (I would also have rather done without the super-hacker character à la Lisbeth Salander.)

Watched Still Life (三峡好人) a 2006 film by Jia Zhangke, as it was proposed in the list of my local cinema (which I support during the endless lockdown of cinemas and theatres in France). This is an amazing film, which at the same time feels incredibly remote or alien… It follows two characters arriving by boat on the at the Three Gorges Dam under construction in search of a runaway spouse. The search for their respective spouse takes place among the demolition of the old Fengjie, soon to be drowned under 150 meters of dam water. This demolition makes for a unique soundtrack, workers hammering in cadence as blurred black shades against the sky. The dialogues are full of long silences, except for the background hammering, and it often feels theatrical. But the characters maintain a strong dignity throughout the film and the depiction of the last days of Fengjie is gripping. The film received the 2006 Venezia Golden Lion.

Cooked a few Venetian dishes from a Venetian cookbook that was my Xmas gift. And finished that way past-the-date polenta boxes. Managed to escape unscathed from both the bûche and galette weeks! And found that cooking spelt bread with spelt yeast was unbelievably easy, taking less time to work on the dough than to reach the closest bakery!

Could not manage to achieve a coherent discussion with some anti-vaxxer relatives over the Xmas break. And gave up, still hoping they would change their mind.

Watched the first episodes of The Expanse, which started as a collection of eight novels and eight shorter works, before turning into a TV series which won the 2020 Hugo Award. Enjoyable if a rather conventional setting, with the usual disregard for space physics! Reminded me very much of the Takeshi Kovacs novels.  To quote from Wikipedia, “Ty Franck began developing the world of The Expanse initially as the setting for a MMORPG and, after a number of years, for a tabletop roleplaying game.” Some of the actors are terrific (even though Steven Strait’s Holden painfully reminds me of Kit Harrington’s Jon Snow, to the point I wondered for a while if they were the same actor…)

Panch at the helm!

Posted in pictures, Travel, University life with tags , , , , , , , , , , , , on January 8, 2020 by xi'an

Reading somewhat by chance a Nature article on the new Director of the National Science Foundation (NSF) nominated by Trump (and yet to be confirmed by the Senate), I found that his name Sethuraman Panchanathan was the name of a friend of my wife 30⁺ years ago when they were both graduate students in image processing at the University of Ottawa, Department of Electrical Engineering… And looking further into the matter, I realised that this was indeed the very friend we knew from that time, with whom w shared laughs, dinners, and a few day trips together around Ottawa! While this is not the ultimate surprise, given that science administration is usually run by scientists, taken from a population pool that is not that large, as exemplified by earlier cases at the national or European level where I had some acquaintance with a then senior officer, it is nonetheless striking (and fun) to hear of a friend moving to a high visibility position after such a long gap. (When comparing NSF and ERC, the European Research Council, with French mathematician Jean-Pierre Bourguignon as current director also appearing in a recent Nature article, I was surprised to see that the ERC budget was more than twice the NSF budget.) Well, good luck to him for sailing these highly political waters!

O’Bayes 19/2

Posted in Books, pictures, Running, Travel, University life with tags , , , , , , , , , , , , , , , , , on July 1, 2019 by xi'an

One talk on Day 2 of O’Bayes 2019 was by Ryan Martin on data dependent priors (or “priors”). Which I have already discussed in this blog. Including the notion of a Gibbs posterior about quantities that “are not always defined through a model” [which is debatable if one sees it like part of a semi-parametric model]. Gibbs posterior that is built through a pseudo-likelihood constructed from the empirical risk, which reminds me of Bissiri, Holmes and Walker. Although requiring a prior on this quantity that is  not part of a model. And is not necessarily a true posterior and not necessarily with the same concentration rate as a true posterior. Constructing a data-dependent distribution on the parameter does not necessarily mean an interesting inference and to keep up with the theme of the conference has no automated claim to [more] “objectivity”.

And after calling a prior both Beauty and The Beast!, Erlis Ruli argued about a “bias-reduction” prior where the prior is solution to a differential equation related with some cumulants, connected with an earlier work of David Firth (Warwick).  An interesting conundrum is how to create an MCMC algorithm when the prior is that intractable, with a possible help from PDMP techniques like the Zig-Zag sampler.

While Peter Orbanz’ talk was centred on a central limit theorem under group invariance, further penalised by being the last of the (sun) day, Peter did a magnificent job of presenting the result and motivating each term. It reminded me of the work Jim Bondar was doing in Ottawa in the 1980’s on Haar measures for Bayesian inference. Including the notion of amenability [a term due to von Neumann] I had not met since then. (Neither have I met Jim since the last summer I spent in Carleton.) The CLT and associated LLN are remarkable in that the average is not over observations but over shifts of the same observation under elements of a sub-group of transformations. I wondered as well at the potential connection with the Read Paper of Kong et al. in 2003 on the use of group averaging for Monte Carlo integration [connection apart from the fact that both discussants, Michael Evans and myself, are present at this conference].

stop the rot!

Posted in Statistics with tags , , , , , , , , , , , , on September 26, 2017 by xi'an

Several entries in Nature this week about predatory journals. Both from Ottawa Hospital Research Institute. One emanates from the publication officer at the Institute, whose role is “dedicated to educating researchers and guiding them in their journal submission”. And telling the tale of a senior scientist finding out a paper submitted to a predatory journal and later rescinded was nonetheless published by the said journal. Which reminded me of a similar misadventure that occurred to me a few years ago. After having a discussion of an earlier paper therein rejected from The American Statistician, my PhD student Kaniav Kamary and I resubmitted it to the Journal of Applied & Computational Mathematics, from which I had received an email a few weeks earlier asking me in flowery terms for a paper. When the paper got accepted as such two days after submission, I got alarmed and realised this was a predatory journal, which title played with the quasi homonymous Journal of Computational and Applied Mathematics (Elsevier) and International Journal of Applied and Computational Mathematics (Springer). Just like the authors in the above story, we wrote back to the editors, telling them we were rescinding our submission, but never got back any reply or request of copyright transfer. Instead, requests for (diminishing) payments were regularly sent to us, for almost a year, until they ceased. In the meanwhile, the paper had been posted on the “journal” website and no further email of ours, including some from our University legal officer, induced a reply or action from the journal…

The second article in Nature is from a group of epidemiologists at the same institute, producing statistics about biomedical publications in predatory journals (characterised as such by the defunct Beall blacklist). And being much more vehement about the danger represented by these journals, which “articles we examined were atrocious in terms of reporting”, and authors submitting to them, as unethical for wasting human and animal observations. The authors of this article identify thirteen characteristics for spotting predatory journals, the first one being “low article-processing fees”, our own misadventure being the opposite. And they ask for higher control and auditing from the funding institutions over their researchers… Besides adding an extra-layer to the bureaucracy, I fear this is rather naïve, as if the boundary between predatory and non-predatory journals was crystal clear, rather than a murky continuum. And putting the blame solely on the researchers rather than sharing it with institutions always eager to push their bibliometrics towards more automation of the assessment of their researchers.

O Canada! [Happy 150th birthday!]

Posted in Statistics with tags , , , , , , , , on July 1, 2017 by xi'an

I am just taking off from Paris to Montréal today for MCM 2017, on Canada Day which happens to be the 150th National Day. I have already spent three instances of a Canada Day, in both Ottawa and Banff, but this is the first in Québec and I am curious to see the atmosphere in Montréal for this occasion. If there is anything to see, since the Montréal Jazz Festival is already started…