Austin, Texas, is the best site for Amazon Inc.’s second headquarters, while Pittsburgh ranks No. 5, according to a new report by Moody’s Analytics. The study used Amazon’s (Nasdaq:AMZN) stated preferences and Moody’s understanding of relevant economic factors. Moody’s ranked regions based on five broad categories: business environment, human capital, cost, quality of life and transportation. But if a sixth, geography, is included, Philadelphia would rank first and Pittsburgh second.