Archive for Tufte

Berezina [book review]

Posted in Books, Travel with tags , , , , , on May 14, 2016 by xi'an

On a whim, I bought this “travel book” in a nice bookstore at the end of Rue Mouffetard, Paris, when looking for a weekend travel guide! I was fairly intrigued about this road-trip on an antique Soviet side-car, following the route of Napoleon’s army when retreating from a burning Moscow. In fact, I have always been fascinated by the way Napoleon got mired into the Campaign of Russia, and not only because of Charles Joseph Minard‘s amazing graphical summary of the Campaign! Despite advices from scientists and diplomats, Napoleon did not want to pay any heed to the climate constraints. And he did not account either for the sacrificial tendencies of the Russian troops and irregulars. A predictable disaster of sorts… The book thus commemorates this retreat from Moscow by driving three side-cars to Paris in the heart of winter, in order to coincide with the arrival of the few survivors of the Grande Armée in Paris. The book however gets very quickly boring as the painfully slow and uncertain drive cannot equate the horror of the hundreds of thousands of deaths in Napoleon’s army fleeing back to Paris. Driving by sub-zero temperatures sharing roads with indifferent Ukrainian truck-drivers and repairing every now and then the side-cars that fell apart does not appeal for long, especially when  It only takes the side-cars 13 days to reach Paris and there is no tension in the road trip as they could really stop any time. On top of that, the discourse about the charisma of Napoleon and the complaints about the reduction of our life scope from heroic time to pampered materialists is pretty annoying, and so is the permanent glorification of the Russian soul. This type of chat does not really rise above the level of a blog series, trust an expert!

how far can we go with Minard’s map?!

Posted in Books, Linux, pictures, Statistics, Travel with tags , , , , , , , , , , on October 13, 2014 by xi'an

Like many others, I discovered Minard’s map of the catastrophic 1812 Russian campaign of Napoleon in Tufte’s book. And I consider it a masterpiece for its elegant way of summarising some many levels of information about this doomed invasion of Russia. So when I spotted Menno-Jan Kraak’s Mapping Time, analysing the challenges of multidimensional cartography through this map and this Naepoleonic campaign, I decided to get a look at it.

Apart from the trivia about Kraak‘s familial connection with the Russian campaign and the Berezina crossing which killed one of his direct ancestors, his great-great-grandfather, along with a few dozen thousand others (even though this was not the most lethal part of the campaign), he brings different perspectives on the meaning of a map and the quantity of information one could or should display. This is not unlike other attempts at competiting with Minard, including those listed on Michael Friendly’s page. Incl. the cleaner printing above. And the dumb pie-chart… A lot more can be done in 2013 than in 1869, indeed, including the use of animated videos, but I remain somewhat sceptical as to the whole purpose of the book. It is a beautiful object, with wide margins and nice colour reproductions, for sure, alas… I just do not see the added value in Kraak‘s work. I would even go as far as thinking this is an a-statistical approach, namely that by trying to produce as much data as possible into the picture, he forgets the whole point of the drawing which is I think to show the awful death rate of the Grande Armée along this absurd trip to and from Moscow and the impact of temperature (although the rise that led to the thaw of the Berezina and the ensuing disaster does not seem correlated with the big gap at the crossing of the river). If more covariates were available, two further dimensions could be added: the proportions of deaths due to battle, guerilla, exhaustion, desertion, and the counterpart map of the Russian losses. In the end, when reading Mapping Time, I learned more about the history surrounding this ill-planned military campaign than about the proper display of data towards informative and unbiased graphs.

Medical illuminations [book review]

Posted in Books, pictures, Statistics with tags , , , , on September 27, 2013 by xi'an

Howard Wainer wrote another book, about to be published by Oxford University Press, called Medical Illuminations. (The book is announced for January 2 on amazon. A great New Year gift to be sure!) While I attended WSC 2013 in Hong Kong and then again at the RSS Annual Conference in Newcastle, I saw a preliminary copy of the book and asked the representative of OUP if I could get a copy for CHANCE (by any chance?!)… And they kindly sent me a copy the next day!

 “This is an odd book (…) gallop[ing] off in all directions at once.” (p.152)

As can be seen from the cover, which reproduces the great da Vinci’s notebook page above (and seen also from the title where illuminations flirts with illuminated [manuscript]), the book focus on visualisation of medical data to “improve healthcare”. Its other themes are using evidence and statistical thinking towards the same goal. Since I was most impressed by the graphical part, I first thought of entitling the post as “Howard does his Tufte (before wondering at the appropriateness of such a title)!

“As hard as this may be to believe, this display is not notably worse than many of the others containd in this remarkable volume.” (p.78)

In fact, this first section is very much related with CHANCE in that a large sequence of graphics were submitted by CHANCE readers when Howard Wainer launched a competition in the magazine for improving upon a Nightingale-like representation by Burtin of antibiotics efficiency. It starts from a administrative ruling that the New York State Health Department had to publish cancer maps overlayed with potentially hazardous sites without any (interpretation) buffer. From there, Wainer shows how the best as well as the worst can be made of graphical representations of statistical data. It reproduces (with due mention) Tufte‘s selection of Minard‘s rendering of the Napoleonic Russian campaign as the best graph ever… The corresponding chapters of the book keep their focus on medical data, with some commentaries on the graphical quality of the 2008 National Healthcare Quality Report (ans.: could do better!). While this is well-done and with a significant message, I would still favour Tufte for teaching data users to present their findings in the most effective way. An interesting final chapter for the section is about “controlling creativity” where Howard Wainer follows in the steps of John Tukey about the Atlas of United States Mortality, And then shows a perfectly incomprehensible chart taken from Understanding USA, a not very premonitory title… (Besides Howard’s conclusion quoted above, you should also read the one-star comments on amazon!)

“Of course, it is impossible to underestimate the graphical skills of the mass media.” (p.164)

Section II is about a better use of statistics and of communicating those statistics towards improving healthcare, from fighting diabetes, to picking the right treatment for hip fractures (from an X-ray),  to re-evaluate detection tests (for breast and prostate cancers) as possibly very inefficient, and to briefly wonder about accelerated testing. And Section III tries to explain why progress (by applying the previous recommendations) has not been more steady. It starts with a story about the use of check-lists in intensive care and the dramatic impact on their effectiveness against infections. (The story hit home as I lost my thumb due to an infection while in intensive care! Maybe a check-list would have helped. Maybe.)  The next chapter contrasts the lack of progress in using check-lists with the adoption of the Korean alphabet in Korea, a wee unrelated example given the focus of the book. (Overall, I find most of the final chapters on the weak side of the book.)

This is indeed an odd book, with a lot of clever remarks and useful insights, but not so much with a driving line that would have made Wainer’s Medical Illuminations more than the sum of its components. Each section and most chapters (!) contain sensible recommendations for improving the presentation and exploitation of medical data towards practitioners and patients. I however wonder how much the book can impact the current state of affairs, like producing better tools for monitoring one’s own diabetes. So, in the end, I recommend the reading of Medical Illuminations as a very pleasant moment, from which examples and anecdotes can be borrowed for courses and friendly discussions. For non-statisticians, it is certainly a worthy entry on the relevance of statistical processing of (raw) data.

Terrible graph of the weekend

Posted in Books, Statistics with tags , , , , , on May 2, 2010 by xi'an

Every week, the weekend edition of Le Monde contains a tribune around some statistics and almost irremediably the illustrations are terrible. Witness the one above where the move from 940 millions to more than a billion is completely out of proportions, both for the disk areas and the number of people! Same thing for the split pie chart below:

What’s wrong with a regular pie-chart?! And the increase in disabled planes below is not much better, moving from 5 to 8 plane silhouettes… The illustrators should read Tufte’s books instead of USA Today…!

Ps-I seem to be always picking at Le Monde, but this is only because I have a subscribtion to its weekend edition!