neurodsp.aperiodic.conversions.convert_alpha_exponent

neurodsp.aperiodic.conversions.convert_alpha_exponent(alpha)[source]

Convert a DFA alpha value to the expected powerlaw exponent.

Parameters
alphafloat

Alpha value from a detrended fluctuation analysis.

Returns
exponentfloat

Predicted aperiodic exponent value, representing a 1/f distribution.

References

1

Schaefer, A., Brach, J. S., Perera, S., & Sejdić, E. (2014). A comparative analysis of spectral exponent estimation techniques for 1/fβ processes with applications to the analysis of stride interval time series. Journal of Neuroscience Methods, 222, 118–130. https://doi.org/10.1016/j.jneumeth.2013.10.017

Examples

Convert a DFA alpha value to the expected powerlaw exponent:

>>> convert_alpha_exponent(1)
-1.0