A finite-time singularity in the dynamics of the US equity market: Will the US equity market eventually collapse?
重新检验了美国股票市场增长加速并趋向奇异点的假说，使用新校准方法和包含更多危机数据（如2008年金融危机、新冠疫情）的道琼斯30指数数据，预测奇异点将在2050年6月左右到来。
Fitting Dow Jones 30 index data for the 1790–1999 period into a log-periodic power-law singularity (LPPLS) model, the seminal paper by Johansen and Sornette (2001) was the first to show that the US equity growth rate is accelerating such that the market is growing as a power law toward a spontaneous singularity. Their model suggests that the US equity market will reach this critical point in the year 2052 ± 10 years, signaling an abrupt transition to a new regime. This study re-examines this important issue using (i) a novel approach to calibrate the LPPLS model and (ii) a different data set including >20 years of additional data. The extended data account for the dot.com bubble burst (2000), the Global Financial Crisis period (2008–2009), the COVID−19 crisis (2020−2022), and the ongoing Russian–Ukrainian war (starting in 2022), which are all events with severe consequences for the global economy. The calibrated LPPLS model suggests that the US equity market will reach a singularity condition by June 2050.