Correlation vs. Causality

Take a look at this graph:

Looks like a pretty strong statistical relationship to me. To quote Steve’s Politics Blog (no, not me):

Derek Lowe of Corante’s ‘In the Pipeline’ (a drug-discovery blog) points to this graph in an article by Bristol-Myers Squibb’s Stephen Johnson, titled, The Trouble with QSAR (OR How I Stopped Worrying and Embrace Fallacy).

Lowe writes, ‘The most arresting part of the article is the graph found in its abstract. No mention is made of it in the text, but none has to be. It’s a plot of the US highway fatality rate versus the tonnage of fresh lemons imported from Mexico, and I have to say, it’s a pretty darn straight line. I’ve seen a lot shakier plots used to justify some sweeping conclusions, and if those were justified, well, then I’m forced to conclude that Mexican lemons have improved highway safety a great deal. The vitamin C, maybe? The fragrance? Bioflavanoids?

It just proves my saying:

“Sometimes statistical significances are just measured coincidences.”

HT: Chart Porn

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One response to “Correlation vs. Causality

  1. Sometimes it’s really that simple, isn’t it? I feel a little stupid for not thinking of this myself/earlier, though.

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