TD Ameritrade is letting customers initialize trades over Twitter, the latest attempt by the discount brokerage to attract digitally savvy and younger investors.

The firm’s Twitter “chatbot” resembles the one it launched via Facebook Messenger in August, and it is powered by an algorithm that produces “social signals.” The algorithm sifts through tweets and then rates the relevance of the information to provide “intelligence” to investors, such as volume spikes, live trading quotes and company news.

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