Archive for December, 2009

War memories

Posted in Kids with tags , , on December 31, 2009 by xi'an

Yesterday, I went to see my grandmother and she started talking about the hard times she had during the second World War. Before and after Saint Lô’s bombing. She described how the food restrictions were so harsh during the war years that items like trousers and socks, when available, had to be traded against butter or meat. How the sole delivery of meat my grandparents could pretend to for a whole week was often set aside to be cooked within a piece of bread in the local bakery and was sent as a package to a brother who remained a war prisoner in Pomerania for the whole duration of the war. She even showed us the receipts of all those packages, kept within a jar, which were dutifully delivered by the German post at the time rather than by the Red Cross…. All those privations while another sister who lived in a farm with unlimited access to this restricted food never contributed to support this brother. The same sister who would not lift a finger to help when my grandparents found themselves homeless after Saint Lô’s bombing. A selfish behaviour my grandmother still resents today for they were close family. Much more than the thefts of neighbours right after the bombing, when my grandfather recovered the large knife I saw him using all his life from those neighbours’ table during their lunch. More also than the laundry soiled by German troops occupying the ruins of my grandparents’ house for a few days during the Saint Lô’s battle. The hardships of those years is so remote from our current life that it seems difficult to believe it only happened seventy years ago.

Last submission

Posted in Statistics, University life on December 30, 2009 by xi'an

Today I have handled my last and final submission to Series B as its co-Editor! In concordance with statistics over the past year, the decision was a rejection from the Editor… In my parting letter to the Associate Editors, I wrote

It has been a memorable four year experience and unreservedly a very positive and enriching one! I am actually regretfully stepping down even though I clearly perceive the need for a rotation of Editors (and AEditors) to keep the horizons of the journal open and even (more) though Gareth Roberts is a terrific choice for new Editor!! The experience has been such a positive one due to the high variety and overall high quality of submissions to Series B but also very much thanks to the dedication of past and current AEditors. My duties as Editor have been made immensely easier thanks to the action of yours and of your predecessors, meaning that I could completely rely on your judgement and recommendations to make my final decisions.
I will certainly miss this important part of my life over the 2006-2009 period, even though I am sure I will find other ways to keep connected with both the Royal Statistical Society and the on-going research. All the best to Series B and to its editorial team for the coming years!

The Gathering Storm

Posted in Books with tags , , , on December 29, 2009 by xi'an

“It was not the best way to approach problems. People were much more complex than a set of rules or numbers.” Brandon Sanderson, The Gathering Storm

Being away with no computer of my own, I spent most of yesterday reading the remainder of Brandon Sanderson’s The Gathering Storm. The book ties up as many plots as is possible to cram within 760 pages without turning incoherent and this change of pace from earlier volumes like Crossroads of Twilight makes it quite enjoyable! Among major characters, only Elayne Trakand does not make it into the book, which sees a lot of minor and some major enigmas explained (like Verin’s ambivalence throughout the whole series, through one of the most climactic pages of the whole series). I cannot distinguish the differences between Jordan’s and Sanderson’s styles well-enough to comment on it, but the new book does fit in the series, presumably because the skeleton was sketched by Robert Jordan before his death. (It seems to me however that The Gathering Storm contains more points of views than Jordan’s volumes. For instance, Tuon grows more depth thanks to those.)

“I don’t know the numbers but he claimed it would be days’ worth of work. And he said that his estimates were probably too optimistic.” Brandon Sanderson,, The Gathering Storm

The most successful subplot in The Gathering Storm certainly is the resolution of the White Tower split and the recognition of Egwene as their leader by both sides. This was predictable, of course, but the way the political maneuvering is presented is quite convincing (except maybe for the way Elaida is deposited). Rand’s part is only slightly less successful but the description of his progression towards madness and his estrangement from Min are both gripping. His move towards a grey zone between good and evil where the destruction of The Dark One starts justifying anything is quite successfully told and while it infuses unease in the reader’s connection with Rand, it also gives him much more depth. The meeting with Rand’s father and the final chapter where he shakes off some of this madness are major stepping stones  in the story. Tuon’s resistance to Rand’s pull also comes as a surprising twist in the overall plot and, while it creates an opening for yet other sub-stories, like the Seanchan’s attack on Tar Valon, it overall makes sense that the two major players cannot agree to be led by one of them. Mat’s meandering through Murandy is definitely a minor story and a lot of details are repetitive of earlier volumes, while Perrin’s indecision takes a while to vanish. The most incomprehensible part is Lan’s, who seems to be taking months to march to his death… The complete disappearance of the Whitecloacks from the political and military scenes is unexplained, as is the absence of Morgase who could as well be dead.

Student abroad

Posted in University life with tags , on December 26, 2009 by xi'an

Last week, a fourth year student on an exchange program with the University of Chicago came to talk to me on her winter break in Paris. She had a few questions about her choices of program for the next year but she mostly wanted to share about her experience. The math courses she took in Chicago are mostly postgraduate and PhD courses, and she has had a hard time assimilating them but she nonetheless passed all her first trimester courses and she now intends to start a PhD in mathematical modelling. By going to the US, she has also discovered the virtues of personal and group work, which is somehow lost on our students due to a large load of course hours per week… I was glad to see this plan towards a math PhD unravelling, as so few of our students end up doing research, but I was also reflecting that this exchange student would have been less likely to do so, had she stayed in France, not because of the contents of the courses but because the large number of students in our courses (up to 180 in fourth year!) prohibits personal tutoring and advising… I am also quite sorry the exchange program we had with the University of Chicago has now come to an end, as the single student we sent there every year was always successful and pursued brilliant postgraduate studies.


Posted in Kids with tags , , on December 25, 2009 by xi'an

Given that the cinema in the small town where we go skiing always has a very diverse program, I ended up seeing Avatar with my kids yesterday. (Despite the three afternoon sessions, the hall was packed.) Everyone seemed excited about the film, especially for the special effects that made the planet Pandora where the story takes place so real. I quite agree with the quality of the landscape rendering, as well as with the imaginative fauna and flora that live on the planet. The idea of a connected ecosystem that make the whole planet like a single aspen grove is a very good idea (if directly inspired by this unique feature of aspens). I find the scenario of Avatar very poor, however. The notion of a mining planet with the local inhabitants rebelling against the desecration of their planet is a direct transposition of the settlers-versus-indigenous scenario. There is not an inch of subtlety in the characters: the good guys and the bad guys are clearly identified from the start! The Marines are strangely disobedient for soldiers. The locals are all very nice and full of qualities but they nonetheless need a Marine from Earth to lead them to victory. The end is in particular completely unrealistic. A battle with bows and arrows (and dragons) versus spatial technology does not seem to offer a wide range of possible outcomes! The man-to-man fight concluding the battle is truly ludicrous: the three main characters meeting in a final fight, with again bow and arrow triumphing of a military robot… This movie reminded me of the recent District 9, in particular because the final fight has many common features, except that the scenario choices made in District 9 led to a much better movie. So I completely agree with the analysis of Avatar recently given by Le Monde, namely that the special effects killed the focus of the director and made this movie a good entertainment rather than a masterpiece.

Nice email

Posted in Books, Statistics with tags , on December 24, 2009 by xi'an

I have received the following email that I find a very nice reward for posting our solutions on the web and on arXiv:

Dear Professors Marin and Robert,

I just wanted to thank you for making the solution manual to Bayesian Core freely available. I just ran across it online today.

I’m a mid-career scientist and have spent most of my career in environmental policy. When I want to learn some new aspect of science, math, and/or computing, either for work or for fun (and these two often overlap), the only viable way for me is by self study, usually with a book or online material. I work mainly on my own and don’t have the time or money to take in-depth training courses (which I find to be a relaltively inefficient way for me to learn new things anyway). Having a solution manual available is invaluable when I get stuck or need a hint on a problem. The chance to see how a seasoned expert approaches a wide range of relevant and (hopefully) interesting problems also gives readers access to wisdom that can be difficult to articulate or express in any other way.

I only wish more professors would make solutions available for their textbooks. I understand the concern that students may be tempted (okay, will be tempted) to look at the solutions without trying to solve the problem. On the other hand, from my travels on internet science and math forums there seem to be a non-trivial number of people like me–that is, people with training and interest in science and math who didn’t stop learning just because we exited the university gates. We’re self motivated and not working on a deadline, and therefore have no need to consult a solution manual until we’ve ruminated on a problem long enough to decide we’re genuinely stuck. Access to a solution manual ensures that we can continue to make progress nevertheless.

Thanks again for your generosity.

The point about self-study readers is obviously quite important and I had not realised it earlier. The criticisms on Amazon were exactly about this issue, so I am very glad this manual meets the request of those self-study readers of Bayesian Core. This also reminds me that we need to rush to make half the solutions for “Introducing Monte Carlo Methods with R” available now the book is out!

Gathering Storm: the prologue

Posted in Books with tags , , , on December 23, 2009 by xi'an

Taking advantage of my trip to London, I bought Brandon Saunderson’s The Gathering Storm—with a 40% rebate from a Border store closing out!—and read the Prologue on my way back to Paris. This prologue was long enough for Tor, Jordan‘s publisher, to put it on sale a few weeks before the book came out (!). As usual, the Prologue is made of snapshots of what is happening or is going to happen. As the 12th occurrence of the genre, it obviously is less appealing than the first one but I still find it a clever way to enter the book. I was first annoyed by the initial story where farm people leaving their previous life for good and for war find the time and motivation to discuss with their neighbours of mundane things like where they stored a particular dish for someone else to pick (!) but the following stories are involving more major actors. And not mentioning dress details or shopping list! (I am now in Chapter 2 and the useless descriptions have indeed started!!!) The part involving (yet again) a meeting of the Forsakens is somehow repetitive of earlier meetings but this has always been a weak aspect of the Series. With the exception of Lanfear, Robert Jordan never managed to describe those super-evil baddies and their points of view in a convincing manner: their worries and perspectives are regrettably mundane and short-sighted… Anyway, there is life and action in this Prologue with a major character most unexpectedly but well-deservedly disappearing from the cast.