When Graphs Are a Matter of Life and Death

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MSI
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When Graphs Are a Matter of Life and Death

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When Graphs Are a Matter of Life and Death
Pie charts and scatter plots seem like ordinary tools, but they revolutionized the way we solve problems.
By Hannah Fry

June 14, 2021: Excellent article/review of new book on “A History of Data Visualization and Graphic Communication” (Harvard), Michael Friendly and Howard Wainer in the New Yorker in article When Graphs Are a Matter of Life and Death

A must read!
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The article/review begins with an interesting case study, based on real data, and devised by a pair of clever business professors, which has been shown to students around the world for more than three decades with an interesting twist. Be sure to read the article!
The book review also includes:
  • The book begins with what might be the first statistical graph in history, devised by the Dutch cartographer Michael Florent van Langren in the sixteen-twenties. This was well into the Age of Discovery, and Europeans were concerned with the measurement of time, distance, and location. Such measurements were particularly important at sea, where accurate navigation presented a considerable challenge. Mariners had to rely on error-prone charts and faulty compasses; they made celestial observations while standing on the decks of rocking boats, and—if all else failed—threw rope overboard in an attempt to work out how far from the seabed they were. If establishing a north-south position was notoriously difficult, the spin of the Earth made it nearly impossible to accurately calculate a ship’s east-west position.

    In 1628, van Langren wrote a letter to the Spanish court, in an effort to demonstrate the importance of improving the way longitude was calculated (and of giving him the funding to do so). To make his case, he drew a simple one-dimensional graph. On the left, he drew a tick mark, representing the ancient city of Toledo, in Spain. From this point, he drew a single horizontal line on the page, marking across its length twelve historical calculations of the longitudinal distance from Toledo to Rome. The estimates were wildly different, scattered all across the line. There was a cluster of estimates at around twenty degrees, including those made by the great astronomer Tycho Brahe and the pioneering cartographer Gerardus Mercator; others, including the celebrated mathematician Ptolemy, put the distance between the two cities closer to thirty degrees. All the estimates were too large—we now know that the correct distance is sixteen and a half degrees. But the graph was meant to show just how divergent the estimates were. Depending on which one was used, a traveller from Toledo could end up anywhere between sixty miles outside Rome and more than six hundred miles away, on the plains of eastern Bulgaria.
Many other great stories in the review and i'm looking forward to getting the book.
See the New Yorker article When Graphs Are a Matter of Life and Death