Claude
cd18862115
"Canon" was leaking onto the public site — a nav item, a footer block, a page title, a set of CSS class names. It was also driving content decisions it had no business driving: the backlog was ordered around which references were still unused, which is curation dressed up as planning. The page is now /references/, the list is documented as a bibliography to grow rather than a canon to curate, and the backlog says plainly that a sin earns a slot by being worth a page — sources are found to support it, never the reverse. Adds six sources (Cairo's Truthful Art, Few's Show Me the Numbers, the Economist's audit of its own charts, Kosara's eagereyes, WTF Visualizations, Datawrapper's dual-axis piece) and roughly doubles the citations on the five published sins, to 5-7 each. Two of the new notes point at sources that complicate our own position rather than back it. The Economist essay ships without a URL rather than a guessed one. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01ULE5RRxdQE1ebwefEd2eCM
2.8 KiB
title, summary, poke, category, severity, tags, badChart, fixedChart, date, citations
| title | summary | poke | category | severity | tags | badChart | fixedChart | date | citations | ||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Aspect Ratio That Exaggerates a Trend | Drawn tall and narrow it's a cliff; drawn wide it's a shrug. Same series, both times. | You didn't change a number — you changed the shape of the box, and the trend changed with it. | Misleading Scales | 3 |
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aspect-ratio-bad | aspect-ratio-fixed | 2026-08-05 |
|
The sin
Two panels, twelve identical numbers, one identical y-range of 170–280 ms. The only difference is the shape of the plotting area: one is tall and narrow, one is a conventional landscape rectangle.
The narrow panel reads like an emergency. The wide one reads like a system drifting slowly and predictably. Both are the same 47% rise.
Why it deceives
The eye judges a trend by the angle of the line, and angle is a product of the data and the box you draw it in. Squeeze the width and every segment tilts toward vertical; stretch it and everything flattens toward nothing. Cleveland and colleagues named this the graph's shape parameter and showed the effect is real and measurable, not a matter of taste.
What makes this one slippery is that the sinner usually isn't sinning. Nobody sets out to pick a dishonest aspect ratio — they drop a chart into the space a slide template left them, or a dashboard tile stretches it to fill a column. The distortion arrives by default, which is exactly why it survives review: the numbers are right, the axis is right, and there is nothing to point at.
The repentance
Treat the ratio as an encoding decision, because that's what it is. The classic guidance is to shape the plot so the average slope of the line sits somewhere near 45° — steep enough to read, shallow enough not to shout. Neither extreme above qualifies; the wide panel is the more honest of the two, and it could stand to be a little taller still.
Then hold the shape constant across charts you want compared. A dashboard where each tile stretches to fill its slot has silently given every series a different exaggeration factor, and no reader will know which trends are real.