The Structure of Unemployment
检验了16个OECD国家战后失业率的单位根，发现考虑一次结构性突变后，大多数国家的单位根假设被拒绝，失业持续性大幅下降。
We test for a unit root in postwar unemployment rates for sixteen OECD countries. When a one-time structural break is incorporated, the unit root hypothesis can be rejected for most of the countries and the measured persistence of unemployment falls dramatically. We then test for multiple structural changes and find evidence of one or two breaks for those countries for which the unit root hypothesis could be rejected. Almost all of the breaks are positive, reflecting the sustained rise in European unemployment. The major exception is the United States, where long-term unemployment rose in the 1970s and fell in the 1980s. © 2000 by the President and Fellows of Harvard College and the Massachusetts Institute of Technology