Mindless words can betray whether you're romantically interested in your date -- and scientists built a computer program to find them

Over a couple of drinks, you cover the usual suspects: favourite foods, dream jobs, where you each grew up. On the way home, you wonder: Were they into me? They were smiling a lot, so probably. But they also looked at their watch a few times, so probably not. Now imagine that the whole time you two were talking, scientists were sitting under the table transcribing the conversation.