Suggested Reading: Beautiful Evidence & The Visual Display of Quantitative Information

Edward R. Tufte — The Visual Display of Quantitative Information —2nd ed., Graphic Press, 2001, 197p. ISBN 978-0-9613921-4-7

Edward R. Tufte — Beautiful Evidence —2nd ed., Graphic Press, 2006, 213p. ISBN 978-0-9613921-7-8

(Buy at Amazon.com)

(Buy at Amazon.com)

Tufte is known for his work on visual presentation of information and all his know-how can be found in his two books: we discover his sober, well documented, to-the-point style, and the careful analysis of each graphs and display technique. His style is such that he conveys without ambiguity why he think something “works” or doesn’t.

Suggested Reading: Now You See It

Stephen Few — Now You See It: Simple Visualization Techniques
for Quantitative Analysis — Analytic Press, 2009, 330p.
ISBN 978-0-9706019-8-8

(Buy at Amazon.com)

Having to review papers (and other manuscripts) quite often, I can say that one of the greatest weaknesses (after dismal engrish and bad overall structure) is the display of quantitative information. In this book (which is somewhat redundant with Show Me the Numbers: Designing Tables and Graphs to Enlighten), Few presents us, under a definite business angle, information representation techniques. While Tufte is deeply concerned with the æstheticism of the graphics, Few is oriented toward its communicative power.

This book is « grand public » is contains no math, and discuss little about data analysis, despite being a trend curve here, a variance there, there again a box-plot; the level of the text remains accessible.

INT_MAX is a terrible NaN (Safer Integer Types, Part IV)

I came across a lovely bug lately. Integer arithmetic, especially in C and C++ it seems, is error-prone. In addition to the risk of having the wrong expressions altogether (a logic error, one could say), integer arithmetic is subject to a number of pitfalls, some I have already discussed here, here, and here. This week, I discuss yet another occasion for error using integer arithmetic.

Consider this piece of code, one that you have seen many times probably, at least as a variation on the theme:

Linear Regression Revisited.

I always disliked when a book gives equations and formulas as if of fiat without providing justification or demonstration; and I don’t mind that they skip a few steps as long that I can fill in the blanks myself if I care to. Linear regression is one of those formula we see but we’d like to understand better.

So let us see how to derive the formulas for linear regression and see how they generalize to any number of unknowns.

Shellsort

The game is different whether we consider external data structures—that live partially or totally on disk or over the network—or internal data structures residing entirely in local memory. For one thing, none of the courses I had on data structures I had really prepared me to deal adequately with (large) external data structures; it was always assumed that the computer’s memory was somehow spacious enough to hold whatever data you needed.

However, when you’re dealing with files, you can’t really assume that you can access random locations to read, write, or exchange data at low cost, and you have to rethink your algorithms (or change plans altogether) to take the cost of slow external media into account. Sometimes an algorithm that doesn’t look all that useful in main memory suddenly makes more sense in external memory because of the way it scans its data. One of these algorithms is the Shellsort.

Asterisms in LaTeX

Another trick this week: asterisms. Asterisms are typographic devices used to separate or to call attention to a piece of text without resorting to using a section or chapter. While its usage in modern English (and French, for that matter) is now rare, it is still an interesting device to structure text.

The usual manifestation of an asterism is the ⁂ symbol (U+2042) but the single character asterism may not be suitable for all occasion. In HTML, and in these posts, you have seen it quite often. With , getting an decent-looking asterism is not that easy.

It made my day

IMMD: Being cited in http://tinyurl.com/4du575o

1968–1993

You know you’re old when you find stuff that commemorates something that happened 43 years ago and it was around the time you were born. Rummaging through my game cupboard (the one where you stuff all the monopoly versions you received for Christmas 26 years ago), I found this playing card set celebrating Intel‘s 25th anniversary.

Sustainable iPod Rack

This week, I have a half-an-hour project for you: A sustainable iPod rack. All you need is a 50 mm × 50 mm × 70 mm (2in × 2in × 2½in) block a wood, a band saw, and a chisel.

OK, it’s not entirely made of wood; you may also need felt pads underneath to make it more stable and/or furniture friendly.

RetroComputing

There are plenty of web sites and museums dedicated to the computers of yore. While most of them now seems quaint, and delightfully obsolete, there are probably a lot of lessons we could re-learn and apply today, with our modern computers.

If you followed my blog for some time, you know that I am concerned with efficient computation and representation of just about everything, applied to workstation, servers, and embedded systems. I do think that retro-computing (computing using old computers or the techniques of old computer) has a lot to teach us, and not only from an historical perspective.