Business Cycle Duration Dependence Reconsidered
用更灵活的广义威布尔模型重新检验商业周期的持续时间依赖性，发现所有样本都存在依赖性，且该模型优于传统威布尔模型。
Sichel estimated a Weibull hazard model using the National Bureau of Economic Research business cycle chronology and found evidence of duration dependence only for prewar expansions and postwar contractions. The article updates the postwar sample through the end of the most recent expansion and uses a generalized Weibull model that provides much greater flexibility at the expense of one additional parameter. This model finds evidence of duration dependence for all samples and is statistically superior to the conventional Weibull model for all samples except postwar contractions.