A recent survey found that people who watch public television have more sex than people who do not. “Who would have thought,” the researchers reported, “that National Geographic Specials or Ken Burns’...

A recent survey found that people who watch public television have more sex than people who do not. “Who would have thought,” the researchers reported, “that National Geographic Specials or Ken Burns’ history of baseball could get people in the mood?” How would you explain this correlation?