Fractal and Complexity Metrics for Activity Time Series

Two nonlinear complexity and scaling metrics for accelerometer activity time series: Detrended Fluctuation Analysis (DFA) and Multiscale Sample Entropy (MSE). Both run in base R (only stats is used) so they add no new runtime dependency. They measure the temporal structure (long-range correlations and information-theoretic complexity) of minute-level activity counts, alongside the amplitude- and timing-based circadian metrics in circadian.rhythm.

References

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