Hysteresis and the Welfare Effect of Corrective Policies: Theory and Evidence from an Energy-Saving Program
研究发现巴西一项为期9个月的节能政策导致居民用电量下降23%，其中一半的降幅持续了至少12年，表明能源需求存在显著的滞后效应；忽略这一效应会严重偏误政策福利评估。
This paper provides stark evidence of hysteresis—the failure of an effect to reverse itself as its underlying cause is reversed—in energy demand. We estimate that half of the 23% reduction in residential electricity use caused by a 9-month-long policy that was imposed on millions of Brazilians has persisted for at least 12 years. We examine the implications of our finding by extending the traditional welfare analysis of corrective policies to allow for hysteresis. Our estimate highlights that failing to take hysteresis into account could severely bias the welfare evaluation of policies aimed at reducing (long-run) energy demand.