Log onto an online dating site and you are asking a machine for romantic assistance. That's cool, but you might as well understand how it works, right?

There's an algorithm picking and choosing which profile to put in front of which users, and sometimes it works—roughly a third of marriages these days begin online—and other times it doesn't. On this week's New Tech City, host Manoush Zomorodi tracks down some smart people who are writing, and improving the matching systems of dating sites.

Kenneth Cukier, data editor at The Economist, explains "you'd be a fool to try to do online dating without machine intelligence, without machine learning." So we get him to explain what that means.

Kang Zhao, professor of management sciences at the University of Iowa, is a very smart guy who has a plan to make sure the matches in front of you are people you'd actually like, and who will actually respond to your messages. "There are ways to improve [profiles] because the information you have in your profile is sometimes just too much."

And then we put all this to someone responsible for a whole lot of online meetings, VP of matching for eHarmony, Steve Carter, who says a few unexpected things, including that dating sites only work if you shake up your rigid mindset and embrace the real life, offline magic of face-to-face dating.