Long Wen, Zhao Manyi, Tang Yeran
School of Economics & Management, University of Chinese Academy of Sciences, Beijing 100190, PR China.
Research Center on Fictitious Economy & Data Science, Chinese Academy of Sciences, Beijing 100190, PR China.
Int Rev Financ Anal. 2021 Jan;73:101612. doi: 10.1016/j.irfa.2020.101612. Epub 2020 Oct 20.
The volatility index is the implied volatility calculated inversely from the option prices. This study investigates whether the official Chinese volatility index, iVX, can represent investor sentiment. In order to describe investor sentiment comprehensively, we build a three-dimensional investor sentiment measurement system composed of macro, and micro level, and decompose iVX into three components to obtain short-term, medium-term fluctuations and long-term trend by EEMD method. The relationships between iVX, its components and sentiment indexes at each level have been analyzed separately, and the empirical results reveal all components of iVX can reflect the investor sentiment at the corresponding level but to which extent they can reflect are not the same. Further we introduce the mixed-frequency dynamic factor analysis to extract the common sentiment factor, which shows stronger correlation with contemporaneous iVX, compared with the sentiment indexes at each level. The ADL model in robustness check also demonstrates the results. Our findings confirm iVX can represent the common sentiment and expectations of Chinese investors in different time scales.
波动率指数是根据期权价格反向计算得出的隐含波动率。本研究调查中国官方波动率指数iVX是否能够代表投资者情绪。为了全面描述投资者情绪,我们构建了一个由宏观和微观层面组成的三维投资者情绪度量体系,并通过经验模态分解(EEMD)方法将iVX分解为三个组成部分,以获得短期、中期波动和长期趋势。我们分别分析了iVX及其组成部分与各层面情绪指数之间的关系,实证结果表明iVX的所有组成部分都能反映相应层面的投资者情绪,但反映程度不尽相同。进一步地,我们引入混合频率动态因子分析来提取共同情绪因子,结果显示该因子与同期iVX的相关性比各层面情绪指数更强。稳健性检验中的自回归分布滞后(ADL)模型也证实了这一结果。我们的研究结果证实,iVX能够代表中国投资者在不同时间尺度上的共同情绪和预期。