An article in Bloomberg BusinessWeek in 2013 reported that Fed Chairman Ben Bernanke testified to Congress that: "If we see continued improvement and we have confidence that that is going to be sustained, then we could- in the next few meetings-we could take a step down in our pace of purchases." According to the article, Bernanke also told Congress that " ‘premature tightening' could ‘carry a substantial risk of slowing or ending the economic recovery.' "
a. What purchases is Fed Chairman Bernanke referring to?
b. Why might a "premature tightening" of the "pace of purchases" slow down the economic recovery?