Archive for Joe Abercrombie

are pseudopriors required in Bayesian model selection?

Posted in Books, Kids, pictures, Statistics, University life with tags , , , , , , , , , , on February 29, 2020 by xi'an

An interesting question from X validated about constructing pseudo-priors for Bayesian model selection. Namely, how useful are these for the concept rather than the implementation? The only case where I am aware of pseudo-priors being used is in Bayesian MCMC algorithms such as Carlin and Chib (1995), where the distributions are used to complement the posterior distribution conditional on a single model (index) into a joint distribution across all model parameters. The trick of this construction is that the pseudo-priors can be essentially anything, including depending on the data as well. And while the impact the ability of the resulting Markov chain to move between spaces, they have no say on the resulting inference, either when choosing a model or when estimating the parameters of a chosen model. The concept of pseudo-priors was also central to the mis-interpretations found in Congdon (2006) and Scott (2002). Which we reanalysed with Jean-Michel Marin in Bayesian Analysis (2008) as the distinction between model-based posteriors and joint pseudo-posteriors.

a little hatred [book review]

Posted in Books, pictures with tags , , , , , , , , on February 2, 2020 by xi'an

While the last books of Joe Abercrombie [I read] were not as exhilarating as the earliest ones, this first volume of a new trilogy brings back memories of the excitement of reading a radically new form of fantasy. Of realistic fantasy if both terms can be twinned together!

“Why folk insisted on singing about great warriors all the time, Rikke couldn’t have said. Why not sing about really good fishermen, or bakers, or roofers, or some other folk who actually left the world a better place, rather than heaping up corpses and setting fire to things?”

A little hatred (an obvious understatement!) takes place one to two generations later than the First Law trilogy. Meaning that the anti-heroes from the previous books have by now either died (a fairly common occurrence in Abercrombie’s universe) or aged a lot (more uncommon, except for magii—whose role is rather unclear in this story) and lost in influence for most of them. The new central characters are thus children or grand-children of these ancient characters as the clannish and feudal power structures of this universe do not allow for much social upheaval, except when workers unite and turn Luddites! The society has indeed evolved towards a sort of industrial revolution with landowners expelling farmers and turning them (as well as former soldiers) into cheap labour for emerging factories, just as in the historical England of the 19th Century… The rebellion of the workers in one of the factory towns is the main event of A little hatred and Abercrombie’s description of the event is fantastic (and ghastly). Much more than the millionth battle between the North and the Union, which ends up in a macho duel. And shows the clear superiority of female characters in that story.  I thus hope the sequel will keep up with this renewed creativity of the author!

blackwing [book review]

Posted in Books, pictures with tags , , , , , , , , , on August 10, 2019 by xi'an

Another fantasy series of the gritty type, maybe not up to the level of the first ground-breaking Abercrombie’s but definitely great!  With some reminiscence of Lawrence’s first series but with a better defined and more complex universe and a not so repulsive central character. Maybe even not repulsive at all when considered past and current actions as described from his perspective…

“I’ve run the equations on it. It took me two days to plot them. Bear in mind that this is far, far beyond any light matrix that I’ve seen calculated before.”

The whole book is indeed written from Captain Ryhalt‘s viewpoint. A bounty hunter for a post- and pre-apocalyptic society, returning fugitives’ head to the central authorities but governed by a Nameless deity on top of everything (?). Appearing as a raven, hence the compelling cover, hence me buying the book! The plot is unraveling at such a pace that it keeps the tension going, especially since it is rather unpredictable. As noted above, it creates a fairly original universe and while magic is heavily involved, there are limitations to the powers of the sorcerers, witches,  half-gods and other entities that mean no deus-ex-machina last minute resolution, sort of. Actually (spoiler alert!) the machine at the core of the story is not doing too well… With repeated mentions made of mathematics governing the handling of the machine, including one over-the-top computation on the ceiling of a cell! It is only when I finished the book that I realised this was part of a series, as the story could have ended there. (Maybe should have, if the associated reviews for the next two volumes are to be trusted.)

La peste et la vigne [book review]

Posted in Books, Kids, Travel with tags , , , , , , , on March 17, 2019 by xi'an

During my trip to Cambodia, I read the second volume of this fantasy cycle in French. Which I liked almost as much as the first volume since the author continues to explore the mystery of the central character Syffe and its relations with some magical forces at play in his universe. As in most stories uniquely centred on a single character point of view the recurring ponderings of Syffe about his role in life, the existence of supernatural forces, and his own sanity may tend to get annoying at time. But the escape from the mines and the subsequent stay in a mountain kingdom are well-paced, especially the description of the plague that allows such an escape. The last section is more connected with the first volume and sees more warfare, again with sudden reversals of fortune (no further spoiler!). The final chapters see a lot explained about many aspects of the story and the raison d’être of the character, even though the very last surprise is somewhat predictable. But opening new vistas for the future volumes. There are still many threads I could have pulled to point some potential influences of earlier cycles, from Stephen Donaldson’s Thomas Covenant chronicles, which I simply hated!, to Robin Hobb’s Soldier’s son. Since both stories convey the feeling of a magical force at the level of the whole land (or universe), with the unprepared and imperfect “hero” able to impact this land in dramatic ways. And again Elizabeth Moon’s Deeds of Paksenarion for the depiction of mercenary companies…

L’enfant de poussière [book review]

Posted in Books, Kids with tags , , , , , , , , , on February 3, 2019 by xi'an

I read this book in French, as this was the language in which it was written and also because I was given a free copy for writing a review! This is a rather unusual book, the first volume of a series called the cycle of Syffe (where Syffe is both the main character and the name of a tribe), well-written by a young author, although the style is at time a wee bit heavy. As for instance in “Les mains sur les hanches, mes yeux balayèrent l’horizon qui semblait s’étaler de la pointe de mes bottes jusqu’au bout du monde.”

The story in itself borrows to some usual memes of the genre, from following a group of young people (very young in this case), forced into dramatic circumstances by the upheaval of their world, here the death of a king leading to a breakup of his kingdom, and meeting unexpected tutors who will turn them into heroes of sort, if they survive the training. The closest books I can think of are (my favourite) Elizabeth Moon’s Deed of Paksenarrion (without the über-religious aspects [so far!]) and Glen Cook’s Black Company, which both follow mercenary companies in a fragmented world at war. A little bit of Mark Lawrence’s Prince of Thorn as well, since in the later a young kid is driving a band of bandits. And not to forget Joe Abercrombie for the rather similar gritty style. (Gritty enough to make me decide after a few chapters that this was definitely not a young adult novel, as I had doubts about it first.)

The book, first of the cycle, thus follows the misadventures of a very young orphan, and I repeat “very young”, because this is an issue with the story, when 8 to 10 years old are shown in situations and with attitudes that do not sound likely. Even for orphans, even in a medieval world with short lifespans and plenty of economic reasons to turn kids into cheap labour. From spy, to stable boy, to child-soldier. Without turning to spoilers, there are also a bucketful of fortune reversals in the book, meaning that the surroundings and circumstances keep changing, sometimes really fast, sometimes quite slowly, as with the years when Syffe acquires fighting skills from an old mercenary from a tribe of free and deadly fighters. The pace is still good enough for the book to be a page-turner that I read in less than a week! And the few battle scenes are realistic in the Abercrombie referential, that is, with everyone scared and unclear why they are there. There is also some magic involved, which is always a risk in the plot, but apart from a lengthy passage on a malevolent Dream with much too real consequences (nothing to do with Tel’aran’rhiod in the Wheel of Time!), the author handles it quite well, maintaining an ambivalence in Syffe about his super-natural experiences, supported by one of his mentors’ freethinker ethics. As for the completeness of the background, i.e., the universe imagined by the author, it often feels too provincial, too local, with the incoming wars between the local lords sounding very much parochial, although the scope gets gradually wider, along with the maturation of Syffe and the darkening of the overall atmosphere. After finishing the book, I read that seven volumes in total are planned in the cycle!