neurodsp.aperiodic.conversions.convert_exponent_alpha

neurodsp.aperiodic.conversions.convert_exponent_alpha(exponent)[source]

Convert a powerlaw exponent to the expected DFA alpha value.

Parameters
exponentfloat

Aperiodic exponent value, representing a 1/f distribution.

Returns
alphafloat

Predicted DFA alpha value for the given exponent value.

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 powerlaw exponent for pink noise to the expected DFA value:

>>> convert_exponent_alpha(-1)
1.0

Convert a powerlaw exponent for white noise to the expected DFA value:

>>> convert_exponent_alpha(0)
0.5