1) Train ML algorithm with news text as input and return (or whatever) as output 2) ??? 3) Profit! (About as likely to be profitable in naive implementations as the Underpant Gnomes' schemes, but anyway.)
Check out Schwager's latest book or Google around. There was I believe at least one trader there who used a sophisticated news release algorithm. It's possible it was pre-programmed for various scenarios planned in advance, so maybe not exactly what you had in mind. He did spend a few years and a lot of $$$ building it. I don't think such an algorithm exists out-of-the-box for a retail trader if that's what you had in mind.
The newsfeed I'm using now, Newsware.com, is offering me an API to automatically trade the news. The price is 1500 usd per month. I'm not really sure how it works, or how that integrates into the broker. Anyone know about it?