Should We Reject the Natural Rate Hypothesis?
回顾了弗里德曼自然率假说的两个子假说，并综述了反对它们的宏观和微观证据，认为证据虽具启发性但非结论性，建议政策制定者将其作为零假设但保持开放态度。
Fifty years ago, Milton Friedman articulated the natural rate hypothesis. It was composed of two sub-hypotheses: First, the natural rate of unemployment is independent of monetary policy. Second, there is no long-run trade-off between the deviation of unemployment from the natural rate and inflation. Both propositions have been challenged. The paper reviews the arguments and the macro and micro evidence against each. It concludes that, in each case, the evidence is suggestive, but not conclusive. Policymakers should keep the natural rate hypothesis as their null hypothesis, but keep an open mind and put some weight on the alternatives.