Effect of return intervals on singular spectrum of financial time series

Many natural records exhibit multifractality characterized by the width and maximum of the singular spectrum. This paper study, how the return intervals of the Hang Seng Index affects the characteristic of the spectral function. We find that the multifractality of the financial time series is similar to the property of the return intervals obtained by small threshold q. Although the multifractality can be found in the financial time series and return interval series obtained by different threshold q, we can´t ignore that the characteristic of the return intervals with moderate threshold q become stronger.