In the next years, Keynesian economics were thought of as less important after the publication of John Muth's work called rational expectations. Phelps, with Calvo and John Taylor, started a programme to rebuild Keynesian economics with new ideas about prices and wages being kept the same for certain time. Professor Phelps and John Taylor published research in 1977, about how to calculate wages ("Staggered Wages). During the '70s, Phelps and Calvo worked on research for making contracts using asymmetric information.