A note on fractal dimensions of biomedical waveforms

Department of Electrical Communication Engineering, Indian Institute of Science, Bangalore 560 012, India.
Computers in Biology and Medicine (Impact Factor: 1.9). 09/2009; 39(11):1006-12. DOI: 10.1016/j.compbiomed.2009.08.001
Source: PubMed

ABSTRACT In this paper, we study performance of Katz method of computing fractal dimension of waveforms, and its estimation accuracy is compared with Higuchi's method. The study is performed on four synthetic parametric fractal waveforms for which true fractal dimensions can be calculated, and real sleep electroencephalogram. The dependence of Katz's fractal dimension on amplitude, frequency and sampling frequency of waveforms is noted. Even though the Higuchi's method has given more accurate estimation of fractal dimensions, the study suggests that the results of Katz's based fractal dimension analysis of biomedical waveforms have to be carefully interpreted.

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