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Showing posts from April, 2009

Speaking of pie charts: the implications of GraphJam

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The charts over at GraphJam aren't exactly data-heavy or rigorous, but they are often amusing: Graph by weegee64, via the GraphJam builder . Graph by oliver.wolf, via the GraphJam builder . OK, I'm slightly biased here because for years and years I was a paid observer of pop culture (aka journalist) , so naturally I appreciate the GraphJammers' mockery of rock songs and movies. But this stuff pleases me on a professional level too: People who make charts and graphs out of heretofore unchartable (or at least uncharted) cultural artifacts show themselves to be comfortable with graphical renderings. They know how to create them and they know how to read them. And that's nothing but good news for Synoptical Charts and our fellows in the infoviz biz. The more people speak our (visual) language, the more uses they will find for it, and the more they will eventually find themselves relying on it... I hope.

Charting: not as easy as pie

SEED magazine's recent rundown of the pluses and minuses of charting is well worth a read, especially if you haven't spent hours and hours considering which graphical formats are most effective and why. To wit: Many psychoperceptual studies have explored the human mind’s aptitude for gleaning information from pictures. Unfortunately, the pie chart incorporates tasks that we humans systematically fail to perform accurately, all those exercises that come at the bottom of the hierarchy of perceptual tasks... So although we’re good at comparing linear distances along a scale — judging which of two lines is longer, a task used in bar graphs — and we’re even better at judging the position of points along a scale, pie charts don’t bring those skills to bear. They do ask us compare angles, but we tend to underestimate acute angles, overestimate obtuse angles, and take horizontally bisected angles as much larger than their vertical counterparts. The problems worsen when we’re asked to ...