Memory effect and multifractality of cross-correlations in financial markets

作者:Qiu, Tian*; Chen, Guang; Zhong, Li-Xin; Lei, Xiao-Wei
来源:Physica A: Statistical Mechanics and Its Applications , 2011, 390(5): 828-836.
DOI:10.1016/j.physa.2010.11.011

摘要

We introduce an instantaneous and an average instantaneous cross-correlation function to detect the temporal cross-correlations between individual stocks based on the daily data of the United States and the Chinese stock markets. The memory effect of the instantaneous cross-correlations is investigated by applying the detrended fluctuation analysis (DFA), where the DFA exponents can be partly explained by the correlation function from the common sense. Long-range memory is observed for the average instantaneous cross-correlations, and persists up to a month magnitude of timescale for the United States stock market and half a month magnitude of timescale for the Chinese stock market. In addition, multifractal nature is investigated by a multifractal detrended fluctuation analysis.