## a journal of the plague year² [reopenings]

Posted in Books, Kids, pictures, Travel, University life, Wines with tags , , , , , , , , , , , , , , , , , , , , , , , , on September 30, 2021 by xi'an

Returned to some face-to-face teaching at Université Paris Dauphine for the new semester. With the students having to be frequently reminded of keeping face masks on (yes, the nose is part of the face and need be covered!). I do not understand why the COVID pass did not apply to universities as well. I also continued an on-line undergrad lecture in mathematical statistics, as I found that the amount of information provided to students this way was superior to black-board teaching. (I actually gave some of these lectures in a uni amphitheatre, to leave the students free to chose, but less than 20% showed up.)

Read the very last volume of the Witcher. With a sense of relief that it was over, even though the plot and the writing were altogether pleasant… And Naomi Novik’s Uprooted, with a permanent feeling of amazement at this novel been praised or awarded anything. Once more, I had missed that it was a YA [but not too young!] novel. Still, so many things go wrong, from the overly obtuse main character to the transparent plot, the highly questionable romantic affair between the 100⁺ year old wizard and the 17 year old teenager he more than less ravished from friends and family, to the poor construct of the magic system, and to the (spoiler alert!) rosy ending. As I read the book over two sleepless nights, not much time was lost. And it had some page-turning qualities. But I’d rather have slept better!

Watched Kate, thinking it was a Japanese film, but quickly found to my sorrow it was not. Not Japanese in the least, except for taking place in Tokyo and involving cartoonesque yakuza. To quote the NYT, “as cheap as a whiff of a green tea and musk cologne called Tokyo wafting over a department store counter”. Simply terrible, even lacking the pretense of story distanciation found in Kill Bill… And then came by chance on Time and Tide, a 2000 Hong Kong film, a much better distanced action picture, with enough ellipses and plenty second-degree dialogues, some mixing Cantonese and Portuguese, plus highly original central male and female characters. I am wondering if the same could be filmed today, given the chokehold of the PCC on the Hong Kongese society and the growing censorship of films there.

Had a great month with our garden tomatoes, as we ate most of them. With a dry spell that stopped the spread of mildew and the aggression of slugs. And had a steady flow of strawberries, a second harvest that is not yet over. And more recently (late) figs, although I bring most of them to the department. The fig harvest seems to be less plentiful than last year…  The last and final product of the garden will be a collection of huge butternuts that spontaneously grew out of last year seeds.

## Ailefroide [Alt. 3954m]

Posted in Books, Kids, Mountains, Travel with tags , , , , , , , , , on September 24, 2021 by xi'an

## the traitor Baru Cormorant [book review]

Posted in Books with tags , , , , , on August 25, 2021 by xi'an

“I deal in costs, not faiths.”

I read The Traitor Baru Cormoran by Seth Dickinson over my Corsican vacations, as it was saved on a Kindle conveniently available… I had this book courtesy of Tor, as one free book of the month, and I did not know what to expect. In the end, I read the book over two days as I could not let go!, and I found it a great story, despite its shaky moral stand, which makes the title sound like an understatement. And leaves me with a feeling of being swindled by the author when finishing the book!

“Without any outward sign or motion, in the wreckage of herself, she donned her armor, made it firm around her heart. Raise her mask: a cold discipline, a steel beneath her skin. Grow comfortable, she told herself. It will never come off.”

The story is a Venetian variation, in that a Republic uses trade to conquer nearby duchies and turn the local inhabitants into its own citizens. While imposing its restrictive moral rules and repressing dissent. I have read it in half a dozen books, at least, but this particular variation is nonetheless fresh, due to the novelty in the depiction of the alternative cultures and the strength and depth of most of its characters. They really come to life under the pen of Seth Dickinson and it hurts to see them go when they die, mostly unexpectedly.There is furthermore a mathematical flavour to the story in that the main character Badu Cormoran is (spoiler alert!), an accountant, elected to high functions by a common entrance exam! A less palatable connection with our field is the enforcement of experimental eugenic policies throughout the empire. The final section is a page-turner as the description of a major battle and of its consequence. Again I have read dozens of such descriptions, including the volume long battle of A Memory of Light that brought the Wheel of Time to its close, but this one is quite gripping and not the end of the story. As written above, the main reservation I have about the plot is that Badu is too nicely rendered for her deeds. She has become the mask she was planning to use to bring the Empire down. I was unaware while reading it that this book was the first in a trilogy: the author could and maybe should have stopped at the final scene, which is both the most devastating and the most brilliant part, but also from which it seems impossible to recover…

## The [errors in the] error of truth [book review]

Posted in Books, Statistics, University life with tags , , , , , , , , , , , , , , , , , , , , , , , , , , , , on August 10, 2021 by xi'an

OUP sent me this book, The error of truth by Steven Osterling, for review. It is a story about the “astonishing” development of quantitative thinking in the past two centuries. Unfortunately, I found it to be one of the worst books I have read on the history of sciences…

To start with the rather obvious part, I find the scholarship behind the book quite shoddy as the author continuously brings in items of historical tidbits to support his overall narrative and sometimes fills gaps on his own. It often feels like the material comes from Wikipedia, despite expressing a critical view of the on-line encyclopedia. The [long] quote below is presumably the most shocking historical blunder, as the terror era marks the climax of the French Revolution, rather than the last fight of the French monarchy. Robespierre was the head of the Jacobins, the most radical revolutionaries at the time, and one of the Assembly members who voted for the execution of Louis XIV, which took place before the Terror. And later started to eliminate his political opponents, until he found himself on the guillotine!

“The monarchy fought back with almost unimaginable savagery. They ordered French troops to carry out a bloody campaign in which many thousands of protesters were killed. Any peasant even remotely suspected of not supporting the government was brutally killed by the soldiers; many were shot at point-blank range. The crackdown’s most intense period was a horrific ten-month Reign of Terror (“la Terreur”) during which the government guillotined untold masses (some estimates are as high as 5,000) of its own citizens as a means to control them. One of the architects of the Reign of Terror was Maximilien Robespierre, a French nobleman and lifelong politician. He explained the government’s slaughter in unbelievable terms, as “justified terror . . . [and] an emanation of virtue” (quoted in Linton 2006). Slowly, however, over the next few years, the people gained control. In the end, many nobles, including King Louis XVI and his wife Marie-Antoinette, were themselves executed by guillotining”

Obviously, this absolute misinterpretation does not matter (very) much for the (hi)story of quantification (and uncertainty assessment), but it demonstrates a lack of expertise of the author. And sap whatever trust one could have in new details he brings to light (life?). As for instance when stating

“Bayes did a lot of his developmental work while tutoring students in local pubs. He was a respected teacher. Taking advantage of his immediate resources (in his circumstance, a billiard table), he taught his theorem to many.”

which does not sound very plausible. I never heard that Bayes had students  or went to pubs or exposed his result to many before its posthumous publication… Or when Voltaire (who died in 1778) is considered as seventeenth-century precursor of the Enlightenment. Or when John Graunt, true member of the Royal Society, is given as a member of the Académie des Sciences. Or when Quetelet is presented as French and as a student of Laplace.

The maths explanations are also puzzling, from the law of large numbers illustrated by six observations, and wrongly expressed (p.54) as

$\bar{X}_n+\mu\qquad\text{when}\qquad n\longrightarrow\infty$

to  the Saint-Petersbourg paradox being seen as inverse probability, to a botched description of the central limit theorem  (p.59), including the meaningless equation (p.60)

$\gamma_n=\frac{2^{2n}}{\pi}\int_0^\pi~\cos^{2n} t\,\text dt$

to de Moivre‘s theorem being given as Taylor’s expansion

$f(z)=\sum_{n=0}^\infty \frac{f^{(n)}(a)}{n!}(z-a)^2$

and as his derivation of the concept of variance, to another botched depiction of the difference between Bayesian and frequentist statistics, incl. the usual horror

$P(68.5<70<71.5)=95%$

to independence being presented as a non-linear relation (p.111), to the conspicuous absence of Pythagoras in the regression chapter, to attributing to Gauss the concept of a probability density (when Simpson, Bayes, Laplace used it as well), to another highly confusing verbal explanation of densities, including a potential confusion between different representations of a distribution (Fig. 9.6) and the existence of distributions other than the Gaussian distribution, to another error in writing the Gaussian pdf (p.157),

$f(x)=\dfrac{e^{-(z-\mu)^2}\big/2\sigma^2}{\sigma\sqrt{2\pi}}$

to yet another error in the item response probability (p.301), and.. to completely missing the distinction between the map and the territory, i.e., the probabilistic model and the real world (“Truth”), which may be the most important shortcoming of the book.

The style is somewhat heavy, with many repetitions about the greatness of the characters involved in the story, and some degree of license in bringing them within the narrative of the book. The historical determinism of this narrative is indeed strong, with a tendency to link characters more than they were, and to make them greater than life. Which is a usual drawback of such books, along with the profuse apologies for presenting a few mathematical formulas!

The overall presentation further has a Victorian and conservative flavour in its adoration of great names, an almost exclusive centering on Western Europe, a patriarchal tone (“It was common for them to assist their husbands in some way or another”, p.44; Marie Curie “agreed to the marriage, believing it would help her keep her laboratory position”, p.283), a defense of the empowerment allowed by the Industrial Revolution and of the positive sides of colonialism and of the Western expansion of the USA, including the invention of Coca Cola as a landmark in the march to Progress!, to the fall of the (communist) Eastern Block being attributed to Ronald Reagan, Karol Wojtyła, and Margaret Thatcher, to the Bell Curve being written by respected professors with solid scholarship, if controversial, to missing the Ottoman Enlightenment and being particularly disparaging about the Middle East, to dismissing Galton’s eugenism as a later year misguided enthusiasm (and side-stepping the issue of Pearson’s and Fisher’s eugenic views),

Another recurrent if minor problem is the poor recording of dates and years when introducing an event or a new character. And the quotes referring to the current edition or translation instead of the original year as, e.g., Bernoulli (1954). Or even better!, Bayes and Price (1963).

[Disclaimer about potential self-plagiarism: this post or an edited version will eventually appear in my Book Review section in CHANCE.]

## the liberation [book review]

Posted in Books with tags , , , , , , , , , , on July 9, 2021 by xi'an

The third volume of Ian Tregillis’ The Alchemy Wars arrived in the mail, and I could not resist bing-read it, induced by a heat wave that made anything close to serious work near impossible in the late afternoons… The characters are essentially the same, with two central (human) female characters whose trajectories once again converge to the critical point. Plus, two female robots playing a contrapunt. And the biblical Daniel, reborn from slavery into a free willed, tolerant and pacific being.

“The Clockmakers had been playing a losing game of catch-up (…) They were too soft, too coddled, too accustomed to standing atop the pile. They weren’t well suited to life as underdogs. They were not French.”

The core of the action takes place in Amsterdam, occupied by liberated robots, prone to pogroms as well as re-enslaving other robots. The weakness in the plot is that there is no strong reason these robots do not completely take over the formerly ruling Guild of Alchemists, and lengthy plot-resolving discussions between fighting characters always irk me no end, but the conclusion still feels proper, with the author not at all reluctant to hack at bits and pieces of his character to raise the body-count. À ls George Martin! And the mild philosophical musing about the reversal of dominant-dominated positions in this society are overall enjoyable if not particularly deep. Overall, a striking trilogy.