Guide to spotting data BS

Posted to Mistaken Data  |  Tags: ,  |  Nathan Yau

As we delve deeper into election season, politicians will spit out more and more statistics to lend some factitude to their talking points. Some are real, and others will be less real. David Spiegelhalter for the Guardian provides a nine-point guide on how to sift out the latter.

On estimates and margin of error:

Next time you hear a politician boasting that unemployment has dropped by 30,000 over the previous quarter, just remember that this is an estimate based on a survey. And that estimate has a margin of error of +/- 80,000, meaning that unemployment may well have gone down, but it may have gone up – the best we can say is that it hasn’t changed very much, but that hardly makes a speech. And to be fair, the politician probably has no idea that this is an estimate and not a head count.

Ah, that makes me feel so warm and fuzzy inside.

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