## the dark defiles

Posted in Books with tags , , , , , , on December 28, 2014 by xi'an

The final and long-awaited volume of a series carries so much expectation that it more often than not ends up disappointing [me]. The Dark Defiles somewhat reluctantly falls within this category… This book is the third instalment of Richard K. Morgan’s fantasy series, A Land Fit for Heroes. Of which I liked mostly the first volume, The Steel Remains. When considering that this first book came out in January 2009, about six years ago, this may explains for the somewhat desultory tone of The Dark Defiles. As well as the overwhelming amount of info-dump needed to close the many open threads about the nature of the Land Fit for Heroes.

“They went. They dug. Found nothing and came back, mostly in the rain.”

[Warning: some spoilers in the following!] The most striking imbalance in the story is the rather mundane pursuits of the three major heroes, from finding an old sword to avenging fallen friends here and there, against the threat of an unravelling of the entire Universe and of the disappearance of the current cosmology.  In addition, the absolute separation maintained by Morgan between Archeth and Ringil kills some of the alchemy of the previous books and increases the tendency to boring inner monologues. The volume is much, much more borderline science-fiction than the previous ones, which obviously kills some of the magic, given that the highest powers that be sound like a sort of meta computer code that eventually gives Ringil the ultimate decision. As often, this mix between fantasy and science-fiction is not much to my taste, since it gives too much power to the foreign machines, the Helmsmen, which sound like they are driving the main human players for very long term goals. And which play too often deus ex machina to save the “heroes” from unsolvable situations. Overall a wee bit of a lengthy book, with a story coming to an unexpected end in the very final pages, leaving some threads unexplained and some feeling that style prevailed over story. But nonetheless a page turner in its second half.

## The winds of Winter [Bayesian prediction]

Posted in Books, Kids, R, Statistics, University life with tags , , , , , , , , , , on October 7, 2014 by xi'an

A surprising entry on arXiv this morning: Richard Vale (from Christchurch, NZ) has posted a paper about the characters appearing in the yet hypothetical next volume of George R.R. Martin’s Song of ice and fire series, The winds of Winter [not even put for pre-sale on amazon!]. Using the previous five books in the series and the frequency of occurrence of characters’ point of view [each chapter being told as from the point of view of one single character], Vale proceeds to model the number of occurrences in a given book by a truncated Poisson model,

$x_{it} \sim \mathcal{P}(\lambda_i)\text{ if }|t-\beta_i|<\tau_i$

in order to account for [most] characters dying at some point in the series. All parameters are endowed with prior distributions, including the terrible “large” hyperpriors familiar to BUGS users… Despite the code being written in R by the author. The modelling does not use anything but the frequencies of the previous books, so knowledge that characters like Eddard Stark had died is not exploited. (Nonetheless, the prediction gives zero chapter to this character in the coming volumes.) Interestingly, a character who seemingly died at the end of the last book is still given a 60% probability of having at least one chapter in  The winds of Winter [no spoiler here, but many in the paper itself!]. As pointed out by the author, the model as such does not allow for prediction of new-character chapters, which remains likely given Martin’s storytelling style! Vale still predicts 11 new-character chapters, which seems high if considering the series should be over in two more books [and an unpredictable number of years!].

As an aside, this paper makes use of the truncnorm R package, which I did not know and which is based on John Geweke’s accept-reject algorithm for truncated normals that I (independently) proposed a few years later.

## Crossed Blades [book review]

Posted in Books with tags , , , , , , , on April 13, 2014 by xi'an

## Bared Blade [book review]

Posted in Books with tags , , , , , , on March 23, 2014 by xi'an