If you're a woman on Twitter, chances are you've been harassed, abused or sent threatening messages. In fact, women are sent abusive content on Twitter every 30 seconds, a new investigation finds.

Amnesty International and Element AI, a global artificial intelligence software product company, surveyed millions of tweets received by 778 journalists and politicians from the U.K. and U.S. in 2017. Using machine learning to analyze the data, the group extrapolated just how wide-ranging abuse toward women is on Twitter.

They found that 1.1 million abusive tweets were sent to the women in the study throughout the year. Abuse towards women of color, especially black women, was worse. Black women were 84 percent more likely than white women to be mentioned in abusive tweets related to gender, race and sexuality, and one in 10 tweets mentioning black women was abusive or problematic, compared to one in 15 for white women.

The research revealed that abuse occurred equally across the political spectrum. Female journalists in the study wrote for ideologically varied publications including the Daily Mail, The New York Times, the Guardian, The Sun, Gal-Dem, PinkNews and Breitbart.

"We found that, although abuse is targeted at women across the political spectrum, women of color were much more likely to be impacted, and black women are disproportionately targeted," Milena Marin, senior advisor for tactical research at Amnesty International, explained in a blog post. "Twitter's failure to crack down on this problem means it is contributing to the silencing of already marginalized voices."

The investigation focused on women journalists and politicians, but women from all walks of life experience online abuse.

In February 2017, a video of 27-year-old activist Seyi Akiwowo speaking at the EU Parliament went viral on social media. Akiwowo received a lot of online abuse and reported examples of abusive posts to Twitter, which she said failed to immediately respond to her reports.

"I was called the n— word, and variations of that word, and Twitter's algorithms just couldn't keep up with the abuse I was getting," Akiwowo told TIME.

More than 6,500 volunteers from 150 countries signed up to take part in Amnesty's "Troll Patrol," a crowdsourcing project designed to process large-scale data about online abuse.

"Our abusive behavior policy strictly prohibits behavior that harasses, intimidates or silences another users voice," a Twitter spokesperson told CNBC Make It. "We are also investing in better technology and tools to enable us to more proactively identify abusive, violative material, to limit its spread and reach on the platform and to encourage healthier conversations."

Vijaya Gadde, legal, policy and trust and safety global lead at Twitter, told CNBC Make It in a statement that she would "note that the concept of 'problematic' content for the purposes of classifying content is one that warrants further discussion."

"We work hard to build globally enforceable rules and have begun consulting the public as part of the process — a new approach within the industry," she said.

In its latest biannual transparency report, Twitter said it received reports on over 2.8 million "unique accounts" for abuse, nearly 2.7 million accounts for "hateful" speech, and 1.35 million accounts for violent threats.



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