Comment
In response to David Hawla:
Thanks for that note of clarification. Of course you're correct. Sims looked at two broad periods, roughly 1919-1939 and 1949-1998. Obviously there was a lot of variation in monetary policy within each of those periods, but Sims maintains that the difference between the two periods is greater than the variation within either period. Whether we've now entered a third era remains to be seen -- but of course Sims couldn't have addressed that issue a decade ago.
As far as I know, the published version of Sims's paper is not available online, but there's a draft available on his home page, at http://sims.princeton.edu/yftp/IwarPwar
posted by Brian Hayes
May 6, 2009