Scale invariant multiplier and multifractality of absolute returns in   stock markets
  The statistical properties of the multipliers of the absolute returns are investigated using one-minute high-frequency data of financial time series. The multiplier distribution is found to be independent of the box size $s$ when $s$ is larger than some crossover scale, providing direct evidence of the existence of scale invariance in financial data. The multipliers with base $a=2$ are well approximated by a normal distribution and the most probable multiplier scales as a power law in respect to the base $a$. We unravel that the volatility multipliers possess multifractal nature which is independent of construction of the multipliers, that is, the values of $s$ and $a$. 
Zhi-Qiang Jiang, Wei-Xing Zhou (ECUST)