Twitter announces global change to algorithm in effort to tackle harassment

The system will use behavioral signals - how users react to a tweet - to assess if an account is adding to or detracting from conversations

Twitter is announcing a global change to its ranking algorithm this week, its first step toward improving the "health" of online conversations since it launched a renewed effort to address rampant trolling, harassment and abuse in March.

"It's shaping up to be one of the highest-impact things that we've done," the chief executive, Jack Dorsey ,said of the update, which will change how tweets appear in search results or conversations. "The spirit of the thing is that we want to take the burden off the person receiving abuse or mob-like behavior."