Edward Tufte: The Dispassionate Statistician III

A year in advance of its publication, a chapter from Edward Tufte’s next book, Beautiful Evidence, has been posted on his website under Ask E.T. “Sparklines: Intense, Simple, Word-Sized Graphics,” makes a case for the “wonderful possibility of writing with data graphics.” Thus, a sparkline (or a word-sized graphic) when embedded in a text, “means like a word and shows like a graphic.”

Tufte acknowledges that others before him have embedded graphics within sentences: most notably, he cites the example of Galileo portraying Saturn as “a visual noun” within a sentence of his book Istoria e dimostrazioni intorno alle macchie solari.

Such citations do not quite explain Tufte’s obsessive defense of “sparklines” as the ultimate information graphic — what he terms “a context for nuanced analysis — and perhaps, better decisions.” Nevertheless, he excels in openmindedness: here, he uses his site to prototype his argument, thus initiating an open discussion and feedback loop. The feedback itself is fascinating, and includes detailed technical corrections, queries about “shade, hue and intensity,” grammatical recommendations, and philosophical ruminations about statistics.

Some comments are exercises in pure logic: “‘Sparkline/glucose/128’ seems to have poor flow. In a traditional statement, ‘Glucose 128’ is short for ‘The Glucose level is 128’ or similar. (Your) sparkline has a more awkward interpretation, passively asserting, ‘Here is some data, which is on Glucose, and has an end value of 128.’ A better arrangement would be ‘Glucose/sparkline/128.’ The corresponding meaning would be ‘The Glucose chart has a latest level of 128.'”

I’m easily persuaded. More importantly, though, I’m captivated by corrections that begin, “Dr. Tufte. This is a lovely chapter. Nevertheless, I have some comments, concerns and, in a few cases, corrections.” This excerpt comes from Alex Merz, a biochemist at Dartmouth, who continues: “‘Pieces of our DNA remain much the same as that of the first worms in the muck.’ This is OK, but could be more correctly phrased: ‘Our DNA retains sequences largely unchanged since the first worms.’ The pieces of DNA in our genome are copies, not originals. The bit about the muck is cliche.”

Other writers go on to dispute many facts cited by Tufte on the topic of DNA. It is to the author’s credit that he accepts and, more impressively still, that he responds to such criticism. Indeed, Tufte not only posted his chapter for public critique, but appears to both encourage group discussion and online commentary. Who among us would willingly subject their writing to such “peer review” — let alone, allow our work to be moulded in the process of so doing?