AlQa'dah 29, 1433, Oct 15, 2012, SPA - 2012 Nobel prize for economics was Monday awarded to US economists Alvin E Roth and Lloyd S Shapley "for the theory of stable allocations and the practice of market design," the Royal Swedish Academy of Sciences said, according to DPA. Their research has helped the understanding and improved the performance of many markets, the academy said. The prize is worth 8 million kronor (1.2 million dollars).