Archive for Melbourne

The Magicians [book review]

Posted in Books, Kids, Travel, Wines with tags , , , , , , , , , on September 17, 2016 by xi'an

While in Melbourne, I heard a recommendation for Lev Grossman’s The Magicians and the next day, while checking the Melbourne Writers Festival bookstore, found the book (rather than the Kristoff volume I was seeking), bought it, and read it within a few days.

‘Brakebills will remind readers of Hogwarts, though with more illicit fondling. Grossman has written what could crudely be labeled a Harry Potter for adults.” , NYT

So is this an Harry Potter for adults?! First, I think Harry Potter can be read by adults (if I qualify as adult!). This remark presumably means the book should not be read by young readers, maybe, due to recurrent sex and alcohol consumption, plus some drugs and an overall depressive tone.

Back to Harry Potter, there is the same magical boarding school feeling, even though it is located in upstate New York on the Hudson river.  And not in Scotland. With an equivalent to Quidditch, an evil magician, exams, surly teens, one or two love triangles, &tc. If in a more modern and American way. The difference with Harry Potter is that it also doubles as Narnia! A Narnia eventually turned wrong and sour, but nonetheless a strong similarity of stories and ideas. Of course, this parallel could be seen as an attempt at deconstruction, exhibiting the inconsistencies in the original novels, but it is so subtle it does not feel like it. There are the same encounters with sentient animal creatures, who never reappear after, the same call for Kings and Queens, as in Narnia. This lack of depth at exploring the connections between Harry Potter, Narnia and even some aspects of the Wheel of Time is frustrating in that something great could have come of it. And then… then… comes the worst literary trick in my list, the call to a subterranean quest with endless monsters and accidents! (I obviously exclude Tolkien’ Moria episode from this list!!!) Concluding with the evil character dumping information in the last battle to explain missing bits and pieces in the story.

So, in conclusion, not such a magical book, even though I read it within a few days thanks to my 39 hour trip back to Paris. The Magicians remains too teeny for my taste, hearing self-deprecating depressive monologues occurs way too often to make the main character congenial, and the story has not enough depth or structure to be compelling. A reviewer rightly pointed out it feels like fandom fiction. Rather than a universe on its own. (As for instance Aaronovitch’ Rivers of London series.)

Darwin’s radio [book review]

Posted in Books, Kids, pictures, University life with tags , , , , , , , , , , , , , , , , on September 10, 2016 by xi'an

When in Sacramento two weeks ago I came across the Beers Books Center bookstore, with a large collection of used and (nearly) new cheap books and among other books I bought Greg Bear’s Darwin Radio. I had (rather) enjoyed another book of his’, Hull Zero Three, not to mention one of his first books, Blood Music, I read in the mid 1980’s, and the premises of this novel sounded promising, not mentioning the Nebula award. The theme is of a major biological threat, apparently due to a new virus, and of the scientific unraveling of what the threat really means. (Spoilers alert!) In that respect it sounds rather similar to the (great) Crichton‘s The Andromeda Strain, which is actually mentioned by some characters in this book. As is Ebola, as a sort of contrapoint (since Ebola is a deadly virus, although the epidemic in Western Africa now seems to have vanished). The biological concept exploited here is dormant DNA in non-coding parts of the genome that periodically get awaken and induce massive steps in the evolution. So massive that carriers of those mutations are killed by locals. Until the day it happens in an all-connected World and the mutation can no longer be stopped. The concept is compelling if not completely convincing of course, while the outcome of a new human race, which is to Homo Sapiens what Homo Sapiens was to Neanderthal, is rather disappointing. (How could it be otherwise?!) But I did appreciate the postulate of a massive and immediate change in the genome, even though the details were disputable and the dismissal of Dawkins‘ perspective poorly defended. From a stylistic perspective, the style is at time heavy, while there are too many chance occurrences, like the main character happening to be in Georgia for a business deal (spoilers, spoilers!) at the times of the opening of collective graves, or the second main character coming upon a couple of Neanderthal mummies with a Sapiens baby, or yet this pair of main characters falling in love and delivering a live mutant baby-girl. But I enjoyed reading it between San Francisco and Melbourne, with a few hours of lost sleep and work. It is a page turner, no doubt! I also like the political undercurrents, from riots to emergency measures, to an effective dictatorship controlling pregnancies and detaining newborns and their mothers.

One important thread in the book deals with anthropology digs getting against Native claims to corpses and general opposition to such digs. This reminded me of a very recent article in Nature where a local Indian tribe had claimed rights to several thousand year old skeletons, whose DNA was then showed to be more related with far away groups than the claimants. But where the tribe was still granted the last word, in a rather worrying jurisprudence.

Melbourne coastline [jatp]

Posted in pictures, Running, Travel with tags , , , , , on August 31, 2016 by xi'an

Melbourne sunrise

Posted in pictures, Running, Travel with tags , , , , , , , , , , on August 28, 2016 by xi'an

off to Australia

Posted in pictures, Statistics, Travel, University life, Wines with tags , , , , , , , , , on August 22, 2016 by xi'an

south bank of the Yarra river, Melbourne, July 21, 2012Taking advantage of being in San Francisco, I flew yesterday to Australia over the Pacific, crossing for the first time the day line. The 15 hour Qantas flight to Sydney was remarkably smooth and quiet, with most passengers sleeping for most of the way, and it gave me a great opportunity to go over several papers I wanted to read and review. Over the next week or so, I will work with my friends and co-authors David Frazier and Gael Martin at Monash University (and undoubtedly enjoy the great food and wine scene!). Before flying back to Paris (alas via San Francisco rather than direct).

asymptotic properties of Approximate Bayesian Computation

Posted in pictures, Statistics, Travel, University life with tags , , , , , , , , , , on July 26, 2016 by xi'an

Street light near the St Kilda Road bridge, Melbourne, July 21, 2012With David Frazier and Gael Martin from Monash University, and with Judith Rousseau (Paris-Dauphine), we have now completed and arXived a paper entitled Asymptotic Properties of Approximate Bayesian Computation. This paper undertakes a fairly complete study of the large sample properties of ABC under weak regularity conditions. We produce therein sufficient conditions for posterior concentration, asymptotic normality of the ABC posterior estimate, and asymptotic normality of the ABC posterior mean. Moreover, those (theoretical) results are of significant import for practitioners of ABC as they pertain to the choice of tolerance ε used within ABC for selecting parameter draws. In particular, they [the results] contradict the conventional ABC wisdom that this tolerance should always be taken as small as the computing budget allows.

Now, this paper bears some similarities with our earlier paper on the consistency of ABC, written with David and Gael. As it happens, the paper was rejected after submission and I then discussed it in an internal seminar in Paris-Dauphine, with Judith taking part in the discussion and quickly suggesting some alternative approach that is now central to the current paper. The previous version analysed Bayesian consistency of ABC under specific uniformity conditions on the summary statistics used within ABC. But conditions for consistency are now much weaker conditions than earlier, thanks to Judith’s input!

There are also similarities with Li and Fearnhead (2015). Previously discussed here. However, while similar in spirit, the results contained in the two papers strongly differ on several fronts:

  1. Li and Fearnhead (2015) considers an ABC algorithm based on kernel smoothing, whereas our interest is the original ABC accept-reject and its many derivatives
  2. our theoretical approach permits a complete study of the asymptotic properties of ABC, posterior concentration, asymptotic normality of ABC posteriors, and asymptotic normality of the ABC posterior mean, whereas Li and Fearnhead (2015) is only concerned with asymptotic normality of the ABC posterior mean estimator (and various related point estimators);
  3. the results of Li and Fearnhead (2015) are derived under very strict uniformity and continuity/differentiability conditions, which bear a strong resemblance to those conditions in Yuan and Clark (2004) and Creel et al. (2015), while the result herein do not rely on such conditions and only assume very weak regularity conditions on the summaries statistics themselves; this difference allows us to characterise the behaviour of ABC in situations not covered by the approach taken in Li and Fearnhead (2015);

postdoc position at Monash, Melbourne

Posted in Kids, pictures, Statistics, Travel, University life with tags , , , , , , on June 21, 2016 by xi'an

tram in front of Flinders St. Station, Melbourne, July 28, 2012[David Dowe sent me the following ad for a position of research fellow in statistics, machine learning, and Astrophysics at Monash University, Melbourne.]

RESEARCH FELLOW: in Statistics and Machine Learning for Astrophysics, Monash University, Australia, deadline 31 July.

We seek to fill a 2.5 year post-doctoral fellowship dedicated to extensions and applications of the Bayesian Minimum Message Length (MML) technique to the analysis of spectroscopic data from recent large astronomical surveys, such as GALAH (GALactic Archaeology with HERMES).  The position is based jointly within the Monash Centre for Astrophysics (MoCA, in the School of Physics and Astronomy) and the Faculty of Information Technology (FIT).

The successful applicant will develop and extend the MML method as needed, applying it to spectroscopic data from the GALAH project, with an aim to understanding nucleosynthesis in stars as well as the formation and evolution of our Galaxy (“galactic archaeology”). The position is based at the Clayton campus (in suburban Melbourne, Australia) of Monash University, which hosts approximately 56,000 equivalent full-time students spread across its Australian and off-shore campuses, and approximately 3500 academic staff.

 The successful applicant will work with world experts in both the Bayesian information-theoretic MML method as well as nuclear astrophysics.  The immediate supervisors will be Professor John Lattanzio (MoCA), Associate Professor David Dowe (FIT) and Dr Aldeida Aleti (FIT).