“…Many methods are proposed to empirically uncover the multifractality, such as the partition function approach [2], the structure function approach [3], the wavelet transform approach [4][5][6], the detrended fluctuation approaches [7][8][9], multifractal natural time analysis [10] and so on. By employing the above-mentioned methods, it is found that many financial time series (returns, volatilities, bid-ask spreads, to list a few) from different markets around the world exhibit significant multifractal characteristics [11][12][13][14][15][16][17][18][19][20], which not only inspires people to construct models (multifractal random walk (MRW) [21,22], Markov-switching multifractal (MSM) models [23,24], and (a) E-mail: zqjiang@ecust.edu.cn so on) to replicate such important stylized facts, but also motive researchers to find the sources of multifractality.…”