Answering this question is 1 / 13  BIS central bankers' speeches  inherently difficult because of the complex interaction of our APP with other policy instruments as well as our evolutionary communication about the purchase programme, through which we signalled our intention to start buying bonds and, later, to recalibrate the size and duration of our bond-buying programme in advance.
Governor Stevens describes this as a framework of “constrained discretion”. The ECB’s monetary policy strategy is another. We have often described our approach as being “rule-based, but not rule-bound”. Is there a fundamental difference between “rule-based” behaviour and “constrained discretion”? I do not think so. Rather the differences of language reflect different historical experience and cultural norms.