hard to assess firms'investment activities and the effects of monetary policy without considering the impact of these assets. therefore, i believe that it is necessary to adequately address these changes in the economic structure. the actual economy that central banks face is very complex and changing dynamically. it is of course very important to learn economic theories in textbooks and analyze past experiences. however, when authorities and economic entities make decisions, it is my view that they should pay due attention to various factors, such as these structural changes that may not necessarily be evident from economic models, and continue to examine what needs to be done at the time.

peter praet : communicating the complexity of unconventional monetary policy in emu speech by mr peter praet, member of the executive board of the european central bank, at the 2017 ecb central bank communications conference " communications challenges for policy effectiveness, accountability and reputation ", frankfurt am main, 15 november 2017. * * * central bank communication has been fundamentally affected by the fallout from the global financial and economic crisis. 1 throughout that period, central banks succeeded in preventing a de - anchoring of inflation expectations. to do so, they adopted a broad range of unconventional measures, the functioning of which is very difficult to explain to the public. this applies, for example, to the notion of negative nominal interest rates, which is hard to communicate because it challenges the conventional wisdom that thrift and patience are virtues that deserve pecuniary remuneration. against this backdrop, i would like to discuss three communication challenges that are particularly relevant to the euro area and the ecb ’ s monetary policy. the first challenge is to bear in mind the multi - country nature of our monetary union, which requires communication to be tuned to the specific context of different national audiences so as to ensure broad participation in the public debate on euro area monetary policy. the second challenge for monetary policy communication is to take into account the increasing complexity of monetary policy by ensuring consistency over time and clarifying the state contingency of the policy stance. to ensure consistency over time, it is essential for the central bank to adopt a clear organising framework, centred on the ultimate objective, for the ecb consisting of price stability, and adhering to a state - contingent reaction function that determines how the monetary policy stance adjusts to changing economic conditions. as the economic environment that monetary policy faces may indeed be subject to massive swings, state contingency may entail pronounced differences in the monetary policy stance over time. this, in turn, requires careful explanation – in particular in circumstances that call for unconventional measures and, hence, leave markets and the general public without empirical precedent to help them anticipate and rationalise the central bank ’ s actions. the third challenge is for the communication framework to provide clarity on the use of specific tools in a multi - instrument context, when the central bank reaction function acquires an additional dimension. in normal times, the central bank reaction function mainly specifies the contingencies for loosening, tightening or maintaining a given policy stance. in unconventional times, it also needs to spell out which tool would