This group is a product of Wellesley College and a grant from the National Science Foundation. It tasks itself with investigating rumors and other claims on Twitter for validity, measuring both the spread of the claim (how many people have read it) and its validity. The site also offers blogs for meta-analysis of the misinformation on Twitter it investigates.
They've examined 617 stories through TwitterTrails, so far. For each story, our algorithm measures how widely the story spread and how skeptical users are about its validity. By measuring crowd behavior, the TwitterTrails algorithm allows journalists to investigate claims and determine whether they appear to be true or false.
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