Mortgage rates were little changed Wednesday in light trading. The Mortgage Bankers Association weekly purchase activity index rose 6.3% for the week ending 9/3, while the refinancing activity index fell 3.1%. Results of today’s 10-year Treasury auction will be released at 1:00 PM. The Fed’s Beige Book, a survey of economic activity by its 12 regional banks, will be released at 2:00.