Grasping Reality on TypePad, by Brad DeLong

J. Bradford DeLong (1992), "Productivity and Machinery Investment: A Long Run Look 1870-1980," Journal of Economic History 53: 2 (June), 307-24.

http://www.j-bradford-delong.net/pdf_files/JEH_Machinery.pdf

J. Bradford DeLong (1992), "Noise Trading," in John Eatwell, Murray Milgate, and Peter Newman, eds, New Palgrave Dictionary of Money and Finance (London: Macmillan).