Federal Reserve Chairman Ben S. Bernanke spent six years pushing for an inflation goal. Now that he has it, some investors are betting he’ll breach the 2 percent target in the short run to lower unemployment. The Fed chairman told lawmakers last week that an increase in energy costs will boost inflation “temporarily while reducing consumers’ purchasing power.” He also said the central bank will adopt a “balanced approach” as it pursues its twin goals of price stability and full employment, which it defines as a jobless rate of between 5.2 percent and 6 percent. “The chairman seemed to suggest they will tolerate a ... (full story)