Which airline rewards program gives the most value

SAN FRANCISCO, Calif. (NerdWallet) - Airline rewards programs are complicated. It might seem like you need a Ph.D. in complex systems (or at least fine-print reading) to understand them. But underneath the complex gobbledygook lies a simple pair of questions:How many points or miles do you earn per dollar spent on flights?How much are those points or miles worth?At the end of the day, that’s what an airline loyalty program is about: Rewarding frequent flyers with value (in this case, point