Must-Read: Adam Posen: Some Big Changes in Macroeconomic Thinking from Lawrence Summers: “In the United States, since 1965, there has been a tripling of the non-employment rate…

…for men… 24 and 54… similar trends… elsewhere…. It is a real puzzle to observe simultaneously multi-year trends of rising non-employment of low-skilled workers and declining measured productivity growth. Either we need a new understanding, or one of these observed patterns is ill-founded or misleading…. Unless we can somehow transform that sustained lower demand for workers into the widespread leisure of the sort imagined by Keynes and some science fiction writers, with the income redistribution to support it, I would think this is very bad news for social stability and technological progress….
Unmeasured quality improvement… [the] fraction of the economy… [susceptible] has been rising, so the amount of mismeasurement (and therefore productivity understatement) would be rising…. [Thus] inflation is lower than even its currently low level — and that has the consequence that real interest rates are higher, so monetary policy at present is tighter… [and] farther away from its mandated inflation target…
Recessions in the OECD… in most cases the level of GDP is lower five to ten years afterward than any prerecession forecast or trend…. “The classic model of cyclical fluctuations… around the given trend is not the right model…. The preoccupation of macroeconomics should be on lower frequency fluctuations that have consequences over long periods of time….
Discussing… Abenomics’ results… I asked whether a message we should take from the Japanese experience is to avoid bad states of the economy at almost any cost…. [And] the very language we use to speak of business cycles, of trend growth rates, of recoveries of to those perhaps non-stationary trends, and so on — which reflects the underlying mental framework of most macroeconomists — would have to be rethought.
http://blogs.piie.com/realtime/?p=5259#.Vk-F39oQipc.twitter