Remember the Facebook experiment in 2010 turned out 340,000 extra voters with a single message tweak? 2012 repeat: turned out 270,000 more.pic.twitter.com/xDAYYMZVvS
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The measured group is a minimum: not everyone uses real name so can't be matched. Let's assume ~.5% effect. That is huge! One time message.
The power to turn out about half a percent of the US population with a single message--first past-the-post election--is pretty significant.
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