Alessio Jacona / Flickr cc

Facebook conceded Tuesday that it recently found and fixed a bug that "misattributed some clicks" on video carousel ads as link clicks. The bug occurred on mobile web browsers on smartphones, which drive significantly less traffic to Facebook than mobile app or desktop. Facebook says it will refund all impacted advertisers in full.

This is not an isolated incident. Per MarketingLand, this is the 10th time Facebook has conceded a measurement mistake to advertisers since September, when it revealed it had overestimated video metrics by up to 60% for two years.

Why it matters: The news comes just months after Facebook agreed to be audited by the de facto media watchdog, the Media Ratings Council (MRC), a move that other "walled garden" social platforms, most notably Twitter and Snapchat, have yet to make. The incident proves that although Facebook has taken many steps, including the audit, to ensure accurate measurement and reliability to its ad partners, it's nearly impossible to get it right 100% of the time at its scale.

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Updated 3 hours ago - Politics & Policy

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Illustration: Aïda Amer/Axios

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Pence chief of staff Marc Short tests positive for coronavirus

Marc Short with Katie Miller, Vice President Pence's communications director, in March. Photo: Doug Mills/The New York Times via Reuters

Marc Short, Vice President Mike Pence’s chief of staff, tested positive for the coronavirus Saturday and is quarantining, according to a White House statement.

Why it matters: Short is Pence's closest aide, and was one of the most powerful forces on the White House coronavirus task force.

6 hours ago - World

Opposition leader Leopoldo López flees Venezuela

Venezuelan opposition politician Leopoldo López outside the Spanish embassy in Caracas, in 2019. Photo: Juan Barreto/AFP via Getty Images

Leopoldo López, a former political prisoner and prominent Venezuelan opposition leader, has left the country, his Popular Will party confirmed in a statement Saturday.

Why it matters: He's been an influential force in the push to oust President Nicolás Maduro's regime and a mentor to opposition leader Juan Guaidó. He'd been in the Spanish ambassador's Caracas residence since escaping house arrest in April 2019 following a failed military uprising.