Summers: Advanced Economies are So Sick

Larry Summers:

Advanced economies are so sick we need a new way to think about them: ...Hysteresis Effects Blanchard Cerutti and I look at a sample of over 100 recessions from industrial countries over the last 50 years and examine their impact on long run output levels in an effort to understand what Blanchard and I had earlier called hysteresis effects. We find that in the vast majority of cases output never returns to previous trends. Indeed there appear to be more cases where recessions reduce the subsequent growth of output than where output returns to trend. In other words “super hysteresis” to use Larry Ball’s term is more frequent than “no hysteresis.” ...

In subsequent work Antonio Fatas and I have looked at the impact of fiscal policy surprises on long run output and long run output forecasts using a methodology pioneered by Blanchard and Leigh. ... We find that fiscal policy changes have large continuing effects on levels of output suggesting the importance of hysteresis. ...

Towards a New Macroeconomics My separate comments in the volume develop an idea I have pushed with little success for a long time. Standard new Keynesian macroeconomics essentially abstracts away from most of what is important in macroeconomics. To an even greater extent this is true of the DSGE (dynamic stochastic general equilibrium) models that are the workhorse of central bank staffs and much practically oriented academic work.

Why? New Keynesian models imply that stabilization policies cannot affect the average level of output over time and that the only effect policy can have is on the amplitude of economic fluctuations not on the level of output. This assumption is problematic...

As macroeconomics was transformed in response to the Depression of the 1930s and the inflation of the 1970s, another 40 years later it should again be transformed in response to stagnation in the industrial world. Maybe we can call it the Keynesian New Economics.