Sun Zequn, Fisher Thomas J
Department of Public Health Sciences, Medical University of South Carolina, Charleston, SC, USA.
Department of Statistics, Miami University, Oxford, OH, USA.
J Appl Stat. 2020 Jun 23;48(11):2042-2063. doi: 10.1080/02664763.2020.1783519. eCollection 2021.
We study the problem of determining if two time series are correlated in the mean and variance. Several test statistics, originally designed for determining the correlation between two mean processes or goodness-of-fit testing, are explored and formally introduced for determining cross-correlation in variance. Simulations demonstrate the theoretical asymptotic distribution can be ineffective in finite samples. Parametric bootstrapping is shown to be an effective tool in such an enterprise. A large simulation study is provided demonstrating the efficacy of the bootstrapping method. Lastly, an empirical example explores a correlation between the Standard & Poor's 500 index and the Euro/US dollar exchange rate while also demonstrating a level of robustness for the proposed method.
我们研究了确定两个时间序列在均值和方差上是否相关的问题。探索并正式引入了几种最初用于确定两个均值过程之间的相关性或拟合优度检验的检验统计量,以确定方差中的互相关性。模拟表明,理论渐近分布在有限样本中可能无效。参数自抽样被证明是这种情况下的一种有效工具。提供了一项大型模拟研究,证明了自抽样方法的有效性。最后,一个实证例子探讨了标准普尔500指数与欧元/美元汇率之间的相关性,同时也证明了所提出方法的稳健性。