COARSE GRAINING IN COMPLEXITY ANALYSIS OF EEGII. THE INFLUENCE OF QUANTIZATION ON COMPLEXITY ANALYSIS
脑电图复杂度分析中的粗粒化问题II.量化对复杂度计算的影响

Our previous paper indicated that a coarse graining preprocessing might result in a loss of information in the original signal, when a complexity analysis was done for biomedical signals; and even in some cases the dynamic property of the original signal might be changed radically due to such preprocessing. The quantization process is also coarse graining processing, thus the risk mentioned above should be considered when the original data were quantized. Compasing the influence of the degree of quantization on C0 complexity and on approximate entropy (ApEn) values calculated for some typical time series, we found that, generally speaking, such influence is not significant, except for some extreme cases such as the binary quantization. Practical calculation of EEG data confirmed the above conclusion.