Multifractal behavior in the dynamics of Brazilian inflation indices

In this paper, we applied the Multifractal Detrended Fluctuations Analysis (MF-DFA) to investigate the components of the observed multifractality in time series of 6 Brazilian inflation indices. We found the generalized Hurst exponent h(q) for each Brazilian inflation indices and quantify their statistical properties, which allowed us to observe separately the small scale contributing (primarily via the negative moments q) and the large scale (via the positive moments q). We also calculated the multifractal spectrum f(α) and used a fourth-degree polynomial regression fit to estimate the complexity parameters that describe the degree of multifractality of the underlying process. We compared the MF-DFA results for the original time series with those for shuffled series. We found that its multifractal nature is due to two factors: broadness of probability density function of the times series and different correlations in small and large scale fluctuations. •Evaluation of Brazilian inflation indices from the multifractal perspective.•Multifractal Detrended Fluctuation Analysis applied in 6 series.•Brazilian inflation has a persistence behavior (the parameter α0>0.5).•The Brazilian inflation indices present an inertial inflation behavior.