A new method to determine a fractal dimension of non-stationary biological time-serial data.
We devised a new analysis using quartile deviation of integrated and subtracted fluctuation, termed QIS-A, to determine a fractal dimension of non-stationary fluctuation. In the algorithm, computations of the quartile deviation, Q(n), of all integrated and subtracted fluctuations are repeated over all scales (n). The fractal scaling exponent is determined as a slope of the line relating log Q(n) to log n. Comparison of the QIS-A and a spectral analysis using 20 computer-simulated fractional Brownian motions demonstrates robustness of the QIS-A to non-stationary fluctuations.
Shono
H
H
Department of Obstetrics and Gynecology, Saga Medical School, 5-1-1 Nabeshima, Saga 849-8501, Japan. shonoh@post.saga-med.ac.jp
Peng
C K
CK
Goldberger
A L
AL
Shono
M
M
Sugimori
H
H
D000465:Algorithms; D003198:Computer Simulation; D017709:Fractals; D006801:Humans; D016018:Least-Squares Analysis; D016014:Linear Models; D009038:Motion; D012815:Signal Processing, Computer-Assisted; D013997:Time Factors