Unit roots in macroeconomic time series: a post Keynesian interpretation

The theme of unit roots in macroeconomic time series has received a great amount of theoretical and applied research in the last two decades. This paper focuses on the implications of the existence of unit roots for macroeconomic theorizing. It is argued that the presence of unit roots in GNP time series provide support to the general perspective adopted by Keynes and post Keynesians on output and employment fluctuations, on the non-neutrality of money in the long run, and on some economic policy issues.